tag:theconversation.com,2011:/us/topics/insecticide-treated-bed-nets-26963/articlesInsecticide-treated bed nets – The Conversation2022-11-04T06:57:52Ztag:theconversation.com,2011:article/1933992022-11-04T06:57:52Z2022-11-04T06:57:52ZMalaria in Africa: why most countries haven’t beaten it yet<figure><img src="https://images.theconversation.com/files/492516/original/file-20221031-21-j9vutx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">80% of malaria deaths are in children younger than five. </span> <span class="attribution"><span class="source">Olympia de Maismont/AFP via Getty Images</span></span></figcaption></figure><p>Malaria remains one of the most devastating parasitic diseases affecting humans. In 2020 there were around 241 million cases and 672,000 malaria-related deaths. This is a sharp <a href="https://www.who.int/publications/i/item/9789240040496">increase</a> from 2019. </p>
<p>One reason it’s so persistent is that the malaria parasite has a very <a href="https://www.cdc.gov/malaria/about/biology/index.html#:%7E:text=The%20malaria%20parasite%20life%20cycle,which%20rupture%20and%20release%20merozoites%20">complex life cycle</a>. It involves many different developmental stages and multiple hosts (mosquitoes and humans). </p>
<p>And in Africa, what adds to the challenge of controlling malaria is that the continent is home to some of the most <a href="https://apps.who.int/iris/bitstream/handle/10665/310862/9789241550499-eng.pdf">efficient malaria vectors</a>. These include <em>Anopheles gambiae</em> and <em>An. funestus</em>. Also, the malaria parasite species <em>Plasmodium falciparum</em>, the <a href="https://www.who.int/news-room/fact-sheets/detail/malaria">dominant species</a> in Africa, is the most lethal. It’s responsible for most malaria cases and deaths – 80% of which occur in children younger than five. </p>
<p>The World Health Organization (WHO) acknowledged these factors when it excluded Africa from its first Global Malaria Eradication Campaign, which ran <a href="https://www.cdc.gov/malaria/about/history/">from 1955 until 1969</a>.</p>
<p>Since then, there have been many advances in malaria control. These include long-lasting insecticide treated nets, malaria rapid diagnostic tests and artemisinin-based combination therapies (ACTs) for malaria treatment. </p>
<p>But malaria elimination is still a challenge. Only <a href="https://www.who.int/teams/global-malaria-programme/elimination/countries-and-territories-certified-malaria-free-by-who">two African countries</a>, Algeria and Morocco, have been certified malaria-free by the WHO. </p>
<p>There are many reasons for the elimination targets remaining out of reach. In this article we highlight four: poverty, human movement, resistance and climate change.</p>
<h2>Poverty</h2>
<p>The limited progress towards malaria elimination is not surprising considering that some of the most malaria-burdened countries in Africa are also some of <a href="https://www.malariaconsortium.org/userfiles/file/Past%20events/factsheet2%20-%20malaria%20and%20poverty.pdf">the poorest countries</a> in the world.</p>
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<a href="https://theconversation.com/ending-malaria-in-africa-needs-to-focus-on-poverty-quick-fixes-wont-cut-it-169205">Ending malaria in Africa needs to focus on poverty: quick fixes won't cut it</a>
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<p>Malaria is both a cause and a consequence of poverty. The disease will therefore remain a significant problem in Africa, if more is not done to improve the socio-economic status of malaria-affected communities. Eliminating poverty to improve the health and well-being of all are part of both the <a href="https://www.un.org/millenniumgoals/">millennium</a> and <a href="https://sdgs.un.org/goals">sustainable</a> development goals. This should be a priority for governments of malaria-endemic countries.</p>
<h2>Mobility</h2>
<p>Africa has one of the fastest growing populations, with a <a href="https://www.migrationpolicy.org/article/africa-intracontinental-free-movement#:%7E:text=The%20African%20continent%20has%20the,region%20is%20growing%20even%20faster">high level of mobility</a>. Marginalised and vulnerable populations are some of most mobile groups within Africa. They travel vast distances across countries with varying malaria transmission intensities. </p>
<p>Human mobility is strongly associated with the global <a href="https://www.gavi.org/vaccineswork/5-reasons-why-pandemics-like-covid-19-are-becoming-more-likely">spread of infectious diseases</a>, as demonstrated by the recent COVID-19, Ebola and monkeypox outbreaks. This presents a challenge to Africa’s malaria elimination aspirations. </p>
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Read more:
<a href="https://theconversation.com/how-africas-porous-borders-make-it-difficult-to-contain-ebola-118719">How Africa's porous borders make it difficult to contain Ebola</a>
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<p>Malaria parasites and mosquitoes do not respect country borders, so malaria services must expand to mobile and marginalised populations. Universal access to effective malaria diagnostics and treatment will reduce the malaria burden by decreasing onward transmission.</p>
<h2>Resistance</h2>
<p>One of the biggest threats to eliminating and eradicating malaria is the <a href="https://www.who.int/news-room/fact-sheets/detail/malaria#:%7E:text=Progress%20in%20global%20malaria%20control,to%20insecticides%20among%20Anopheles%20mosquitoes">emergence and spread</a> of insecticide, diagnostic and drug resistance. </p>
<p>Both the malaria vectors and parasites have proved to be very adaptable. They have rapidly developed mechanisms to survive and multiply in the presence of insecticides and antimalarial drugs, respectively. </p>
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<a href="https://theconversation.com/some-malaria-parasites-are-evading-detection-tests-causing-an-urgent-threat-to-public-health-177258">Some malaria parasites are evading detection tests, causing an urgent threat to public health</a>
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<p>Insecticide resistance is widespread across the <a href="https://www.bdi.ox.ac.uk/news/tracking-the-spread-of-mosquito-insecticide-resistance-across-africa">African region</a>. It reduces the efficacy of strategies based on suppressing vectors, such as long-lasting insecticide treated nets and indoor residual spraying. </p>
<p>To extend the effective lifespan of the available insecticides, the WHO has provided <a href="http://apps.who.int/iris/bitstream/handle/10665/44768/9789241502801_eng.pdf;jsessionid=233E06F6978781E9163F1479ED99F9F7?sequence=1">new guidance</a> in its handbook for integrated vector management. The handbook highlights the importance of routine entomological surveillance to determine the type of vectors present, changes in vector behaviour and the insecticide susceptibility status of the vector. All this information can guide effective vector suppression if available in good time. </p>
<p>Having the correct diagnostic method and treatment in place also hinges on having a robust surveillance system. The system must be capable of generating efficacy data in near real-time to allow for prompt evidence-based decision-making. The need for this type of <a href="https://www.who.int/news/item/28-05-2021-statement-by-the-malaria-policy-advisory-group-on-the-urgent-need-to-address-the-high-prevalence-of-pfhrp2-3-gene-deletions-in-the-horn-of-africa-and-beyond">routine surveillance</a> has become even more urgent as African malaria parasites have developed mutations that allow them to evade detection by the most widely used rapid diagnostic tests on the continent. These undetected cases will go untreated, potentially sustaining onward transmission. The result will be major increases in malaria cases, severe disease, and potentially death.</p>
<p>Besides becoming invisible to rapid diagnostic tests, <em>P. falciparum</em> parasites in many central and west African countries have become <a href="https://www.npr.org/sections/goatsandsoda/2022/02/06/1077953012/drug-resistant-malaria-is-emerging-in-africa-doctors-are-worried-yet-hopeful">resistant</a> to artemisinins. This is a component of the most widely used antimalarials in Africa, ACTs. The spread of artemisinin-resistant parasites will potentially raise case numbers and deaths, repeating the devastating trend observed when drug-resistant parasites previously emerged. The loss of ACTs would severely set back elimination efforts as there are no novel WHO-approved antimalarials currently available. Efforts are needed to prevent the spread of artemisinin-resistant parasites through strong surveillance and containment responses.</p>
<h2>Climate change</h2>
<p>The impact of climate change is complex, but there are <a href="https://www.un.org/en/chronicle/article/climate-change-and-malaria-complex-relationship#:%7E:text=An%20increase%20in%20temperature%2C%20rainfall,it%20was%20not%20reported%20earlier">suggestions</a> that more places will become malaria risk areas. Mosquitoes will now be able to survive and transmit malaria in these warmer areas. This, in turn, will increase malaria cases, severe illness and deaths in the non-immune communities.</p>
<h2>Positive developments</h2>
<p>In spite of these challenges, there is some light at the end of tunnel. </p>
<p>After years of research there are two new malaria vaccines. The first, <a href="https://www.gsk.com/en-gb/media/press-releases/who-grants-prequalification-to-gsk-s-mosquirix-the-first-and-only-approved-malaria-vaccine/">Mosquirix</a>, has been prequalified for use by the WHO. The second, <a href="https://www.medicalnewstoday.com/articles/malaria-new-vaccine-candidate-shows-promise-in-clinical-trials">R21/Matrix M</a>, has shown promising results in phase 2 clinical trials. </p>
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Read more:
<a href="https://theconversation.com/vaccines-could-be-a-game-changer-in-the-fight-against-malaria-in-africa-193233">Vaccines could be a game-changer in the fight against malaria in Africa</a>
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<p>There are new long-lasting insecticide treated nets and insecticide formulations for vector control. There are also novel strategies for parasite suppression. </p>
<p>Adding these tools to the elimination toolbox will assist Africa get closer to malaria elimination.</p><img src="https://counter.theconversation.com/content/193399/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jaishree Raman is affiliated with the National Institute for Communicable Diseases, the Wits Research Institute for Malaria and UP Institute for Sustainable Malaria Control. She received funding from the South African Research Trust, South African Medical Research Council, Bill and Melinda Gates Foundation, the Global Fund, Clinton Health Access Initiative, National Research Foundation and the National Institute for Communicable Diseases</span></em></p><p class="fine-print"><em><span>Shüné Oliver s affiliated with the National Institute for Communicable Diseases and the Wits Research Institute for Malaria and receives funding from the National Research Foundation, the National Health Laboratory Services Research Trust and the Female Academic Leadership fund. </span></em></p>There are many reasons that malaria is so persistent in Africa. Four of them are poverty, human movement, resistance and climate change.Jaishree Raman, Principal Medical Scientist and Head of Laboratory for Antimalarial Resistance Monitoring and Malaria Operational Research, National Institute for Communicable DiseasesShüné Oliver, Medical scientist, National Institute for Communicable DiseasesLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1836542022-05-25T13:23:53Z2022-05-25T13:23:53ZArtificial light may become a new weapon in the fight to control malaria<figure><img src="https://images.theconversation.com/files/465048/original/file-20220524-26-kpfwwo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Artificial light may trick malaria-transmitting mosquitoes into changing their feeding habits, protecting people against bites.</span> <span class="attribution"><span class="source">Professor Lizette Koekemoer/University of the Witwatersrand</span></span></figcaption></figure><p>The world has not yet won the war against malaria. While the total number of cases has declined from about 81.1 cases per 1,000 population to 59 per 1,000 since 2000, there were still an estimated <a href="https://www.who.int/teams/global-malaria-programme/reports/world-malaria-report-2021">240 million cases and 600,000 deaths</a> in 2020 globally. </p>
<p>Malaria remains a menace across Africa. The continent carries by far the world’s <a href="https://www.who.int/teams/global-malaria-programme/reports/world-malaria-report-2021">largest disease burden</a>: 94% of cases and 96% of deaths occur across the continent. Alarmingly, children aged five or younger account for <a href="https://www.who.int/teams/global-malaria-programme/reports/world-malaria-report-2021">80% of these deaths</a>.</p>
<p>There is no room for complacency. While <a href="https://www.who.int/news/item/06-10-2021-who-recommends-groundbreaking-malaria-vaccine-for-children-at-risk">vaccines look promising</a>, there is still a steady rise of antimalarial drug resistance, especially in East Africa. The <a href="https://theconversation.com/some-malaria-parasites-are-evading-detection-tests-causing-an-urgent-threat-to-public-health-177258">parasites are evolving</a> mutations which allow them to escape routine diagnosis. The mosquitoes are also evolving increased <a href="https://theconversation.com/fresh-signs-of-mosquito-insecticide-resistance-in-south-africa-181618">resistance to insecticides</a>.</p>
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<a href="https://theconversation.com/malaria-elimination-in-southern-africa-possibly-but-these-gaps-need-attention-171031">Malaria elimination in southern Africa? Possibly, but these gaps need attention</a>
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<p>This situation underscores the need for sharpening the multiple vector control options, and exploring new strategies. </p>
<p><a href="https://www.frontiersin.org/articles/10.3389/fevo.2021.768090/full">My research</a> explores one such potential strategy: the use of artificial lights to trick malaria-transmitting mosquito species that feed nocturnally into behaving as if it’s daytime. This may deter feeding, helping to keep people safe from malaria-carrying mosquito bites. </p>
<h2>New light</h2>
<p>Light is a fundamental cue in nature. It regulates much of the timing of biological events, like when birds breed, lions hunt – and humans’ sleep patterns. It is also an ancient cue. While species have been exposed to changes in climate cycles over the eons, the timing of day and night has remained relatively constant over evolutionary time, owing to the rotation of the earth. This means that all life on the planet has evolved with such regular day-night cycles. The gene for the <a href="https://www.nccih.nih.gov/health/melatonin-what-you-need-to-know">melatonin hormone</a>, which regulates sleep-awake cycles, is shared between widely different and old taxonomic groups, such as plants and animals.</p>
<p>However, these natural dark cycles are <a href="https://theconversation.com/skyglow-forces-dung-beetles-in-the-city-to-abandon-the-milky-way-as-their-compass-165110">rapidly changing</a> because people are increasingly using artificial light. <a href="https://www.darksky.org/80-of-world-population-lives-under-skyglow-new-study-finds/">Nearly 80%</a> of the world’s people now live under artificially lit skies. </p>
<p>So, what impact might such artificial light use have on malaria? </p>
<h2>Altering mosquito biology</h2>
<p>The <em>Anopheles</em> group of mosquitoes, which is responsible for all of Africa’s malaria cases, is a nocturnal feeder. After mating, the females will seek out a blood meal. In doing so, they transfer the <em>Plasmodium</em> parasite which causes malaria. This is why bed nets are <a href="https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(21)00216-3/fulltext">so effective</a> when used correctly – they block bites when people are sleeping at night.</p>
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Read more:
<a href="https://theconversation.com/curious-kids-what-would-happen-if-all-the-mosquitoes-in-the-world-disappeared-175528">Curious Kids: What would happen if all the mosquitoes in the world disappeared?</a>
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<p><a href="https://parasitesandvectors.biomedcentral.com/articles/10.1186/s13071-017-2196-3">Emerging research</a>, including <a href="https://www.frontiersin.org/articles/10.3389/fevo.2021.768090/full">my own</a>, <a href="https://www.researchgate.net/publication/348313670_Artificial_light_and_biting_flies_the_parallel_development_of_attractive_light_traps_and_unattractive_domestic_lights">argues</a> how artificial light at night can change mosquitoes’ behaviour.</p>
<p>This is because the artificial light used in homes can alter mosquito biology. For example, a short pulse of Light Emitting Diode (LED) light, commonly used lights in homes as “downlights” or reading lamps, can delay the onset of biting by hours in <em>Anopheles</em>, and so reduce biting rates and malaria transfer. The light essentially tricks the mosquitoes into not feeding.</p>
<p>These ideas are promising. But strategies to control vectors don’t always work at a bigger scale, especially if those strategies are not properly applied. For instance, bed nets treated with mosquito repellents are sometimes <a href="https://theconversation.com/mosquito-nets-are-often-used-for-fishing-a-smart-response-is-needed-66283">used as fishing nets</a> in parts of Africa. Demonstrating the effects of artificial light in controlled laboratory settings is one thing, but rolling out their use as an effective vector control strategy is quite another.</p>
<p>Even if governments could easily get LED lights into many homes to guard against malaria-carrying mosquitoes, there might be unintended consequences for human health. A burgeoning <a href="https://www.ama-assn.org/sites/ama-assn.org/files/corp/media-browser/public/about-ama/councils/Council%20Reports/council-on-science-public-health/a16-csaph2.pdf">body of research</a> is examining the effects of artificial light on human health. Early indications are that it can have negative impacts like disrupted sleep.</p>
<h2>A growing body of research</h2>
<p>Overall, it is not yet clear how artificial lights might be used to lessen the risk of malaria infections. But the growing body of work on this issue suggests that it’s a concept which needs more attention from the World Health Organization and other groups.</p>
<p>Once the impacts of artificial light use are more fully understood, developmental planners across Africa might be able to ensure that lights of the correct kinds, used in optimal places and times, become part of the continent’s efforts to control malaria.</p><img src="https://counter.theconversation.com/content/183654/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bernard Coetzee is funded by the Jennifer Ward Oppenheimer Research Grant. It is a US$150 000 grant awarded annually to address pressing environmental issues in Africa. </span></em></p>Artificial lights could trick malaria-transmitting mosquito species that feed nocturnally into behaving as if it’s daytime.Bernard Coetzee, Senior lecturer, University of PretoriaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1733552021-12-08T15:27:14Z2021-12-08T15:27:14ZHalf the world’s people could be at greater risk of malaria if control efforts do not improve<figure><img src="https://images.theconversation.com/files/436309/original/file-20211208-188518-1xg19l8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Indoor residual spraying is one of the main components of malaria control. </span> <span class="attribution"><span class="source">Cristina Aldehuela/AFP via Getty Images</span></span></figcaption></figure><p>The COVID-19 pandemic continues to have a devastating impact on international malaria control and elimination efforts. According to the latest <a href="https://www.who.int/teams/global-malaria-programme/reports/world-malaria-report-2021">World Malaria Report</a>, there were an estimated <a href="https://www.who.int/news/item/06-12-2021-more-malaria-cases-and-deaths-in-2020-linked-to-covid-19-disruptions">14 million</a> more cases of malaria in 2020 compared to 2019. </p>
<p>Even more concerning was the marked increase in malaria-related deaths. These were mainly in children under the age of five living in sub-Saharan Africa. This is a sombre finding. Malaria is a preventable disease. Effective point-of-care diagnostic tools (rapid diagnostic tests) and treatments (artemisinin-based combination therapies) are widely available.</p>
<p>Progress towards achieving a malaria-free world had begun stalling – and in some regions reversing – from 2015. But the COVID-19 pandemic, continual Ebola outbreaks and ongoing humanitarian crises have posed additional challenges for national malaria control programmes. These factors have increased the chances that the 2030 targets set by the World Health Organization (WHO) won’t be met. The <a href="https://www.who.int/docs/default-source/documents/global-technical-strategy-for-malaria-2016-2030.pdf?sfvrsn=c82afcc_0">Global Malaria Strategy</a> goals are to reduce malaria cases and deaths by 90%, and eliminate the disease in 35 countries by 2030. </p>
<p>The WHO warns that without immediate decisive action, all the impressive gains made against malaria since 2000 will be eroded. This will allow malaria to rebound and expose at least <a href="https://www.who.int/news-room/fact-sheets/detail/malaria">half of the world’s population</a> to an increased risk of malaria. </p>
<h2>Responding to the COVID-19 threat</h2>
<p>National malaria control programmes across Africa have been commended for acting against the threat that COVID-19 posed to the delivery of essential malaria services. Disruptions did occur. But prompt innovative actions ensured they <a href="https://www.who.int/news/item/23-04-2020-who-urges-countries-to-move-quickly-to-save-lives-from-malaria-in-sub-saharan-africa">were not at the scale many experts predicted</a> at the start of the pandemic. </p>
<p>Encouragingly, in 2020 many malaria endemic countries achieved their targets for delivering insecticide treated nets and spraying indoors. The number of children receiving seasonal chemoprevention in Africa exceeded the initial target. </p>
<p>However, more needs to be done to get malaria control efforts back on track. There must be improved access to essential malaria services. This is especially important for populations most at risk. Of particular concern are people in sub-Saharan Africa. In this region, six countries – Nigeria, Uganda, Democratic Republic of the Congo, Angola, Mozambique and Burkina Faso – accounted for over 50% of all malaria cases and deaths reported in 2020. </p>
<h2>Threats to effective malaria control</h2>
<p>Both the malaria parasite and the mosquito vector are continually developing mechanisms to evade control interventions. </p>
<p>Malaria parasites resistant to the artemisinin component of the WHO- recommended <a href="https://www.who.int/news-room/fact-sheets/detail/malaria">artemisinin-based combination therapies</a> have now been confirmed in <a href="https://www.healio.com/news/infectious-disease/20210923/resistant-malaria-has-gained-a-foothold-in-africa">Uganda and Rwanda</a>. This raises concerns over whether the therapies will continue to work. </p>
<p>There are currently no effective alternatives to these drugs. The WHO recommends that national malaria control programmes routinely assess whether drugs are still effective and whether parasites are mutating. Countries are also advised to develop feasible, fully costed containment and response plans to use as soon as they detect resistant parasites. </p>
<p>The widespread use of rapid diagnostic tests and artemisinin-based combination therapies enables prompt diagnosis and effective treatment. These actions have made a positive difference to treatment outcomes. </p>
<p>But the current World Malaria Report sounds the alarm over the spread of malaria parasites with genetic changes that make them invisible to the rapid diagnostic tests most widely used in sub-Saharan Africa. </p>
<p>Malaria in pregnancy remains another challenge in Africa. In 2020, about 11.6 million pregnancies were exposed to malaria. As a result, 819,000 infants had low birthweights – which is strongly associated with death in childhood. The WHO recommends making greater efforts to reach pregnant women with interventions. These include insecticide treated nets and <a href="https://www.who.int/elena/titles/iptp-pregnancy/en/">intermittent preventive treatment</a> – where pregnant women are treated for malaria whether they have the disease or not. If 90% of women at risk had been treated, it would have prevented at least 200,000 low-weight births in 2020. </p>
<h2>Improved surveillance and innovation</h2>
<p>Insecticide treated nets and indoor residual spraying are essential to control and eventually eliminate malaria. The WHO applauded all countries that achieved optimal coverage in these efforts, despite the challenges faced in 2020. </p>
<p>Resistance is a threat here too, however. Over 88% of the countries that contributed to the 2020 World Malaria Report reported mosquito resistance to at least one class of insecticide. Nineteen countries reported resistance to all four classes of approved insecticides.</p>
<p>But it’s not all doom and gloom. </p>
<p>Earlier this year the WHO approved the roll-out of the <a href="https://www.who.int/news/item/06-10-2021-who-recommends-groundbreaking-malaria-vaccine-for-children-at-risk">first malaria vaccine</a>, RTS,S, in highly burdened African countries. This vaccine has the potential to significantly improve outcomes in young African children. This group suffers disproportionately from malaria. </p>
<p>There are also new insecticides which could help sustain the efficacy of nets and spraying. And there is increased funding to integrate genomic surveillance into routine malaria surveillance systems. </p>
<p>These and other novel interventions, together with strong political commitment and sustained funding, have the potential to get malaria control efforts back on track and make malaria elimination a reality in our lifetime.</p><img src="https://counter.theconversation.com/content/173355/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jaishree Raman is affiliated with the Laboratory for Antimalarial Resistance Monitoring and Malaria Operational Research at the National Institute for Communicable Diseases, the Wits Research Institute for Malaria and University of Pretoria Institute for Sustainable Malaria Control. She receives funding from the Research Trust, the National Research Foundation, the South African Medical Research Council and the Gates Foundation.</span></em></p>Like the coronavirus causing the current pandemic, both the malaria parasite and mosquito vector are developing ways to avoid control.Jaishree Raman, Principal Medical Scientist and Head of Laboratory for Antimalarial Resistance Monitoring and Malaria Operational Research, National Institute for Communicable DiseasesLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1654132021-08-12T14:50:40Z2021-08-12T14:50:40ZHow we used smartphones to test for malaria: lessons from Uganda<figure><img src="https://images.theconversation.com/files/415686/original/file-20210811-27-ealfdx.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The spread of malaria can be controlled by community-based management. </span> <span class="attribution"><span class="source">Jonathan Cooper</span></span></figcaption></figure><p>Malaria is one of the world’s leading causes of illness and death. Around <a href="https://www.who.int/news-room/fact-sheets/detail/malaria">229 million</a> people are infected each year and more than 400,000 of them die. </p>
<p>The spread of malaria can be controlled by careful and coordinated community-based management. This includes the distribution of insecticide-coated bed nets, drug treatment, and diagnostic testing when available. Diagnostic testing is currently done in the field using microscopes or antibody-based tests. In centralised laboratories, tests are done on high performance, automated machines that combine biochemical reagents with the samples to generate reliable and highly sensitive signals. </p>
<p>As a consequence, diagnostic testing can be a challenge in remote areas of sub-Saharan Africa. Here, access to power, running water, specialist laboratory equipment and trained healthcare professional staff can all be limited. Without diagnostics, treatment is either delayed or based on symptoms alone (which are often similar to those of other infectious diseases).</p>
<p>A 2018 World Health Organisation (WHO) <a href="http://apps.who.int/iris/bitstream/handle/10665/275867/9789241565653-eng.pdf?ua=1">report</a> on controlling malaria highlighted a need for fast and reliable testing that’s available even in the most remote areas. </p>
<p>That report also recommended that disease diagnostics be more digitally integrated into regional or national case management systems to better monitor the spread of malaria.</p>
<p>For several years now, bioengineers from the University of Glasgow have been working with the Vector Control Division of the Uganda Ministry of Health. We’ve been collaborating on new ways to achieve these vital WHO recommendations. Together, we’ve made some <a href="https://www.nature.com/articles/s41928-021-00612-x">key advances</a> towards delivering new devices which empower people with basic medical knowledge to administer malaria tests in the field. Our smartphone-based diagnostics test, analyse and record data securely. </p>
<h2>Field testing</h2>
<p>The most common and accurate malaria test looks for the parasite’s DNA in a person’s blood using a polymerase chain reaction (<a href="https://link.springer.com/article/10.1186/s12936-016-1158-0">PCR</a>). PCR tests require trained staff to take a sample and process it. Tests must be done in laboratory conditions.</p>
<p>More portable and field-ready tests are available. They include <a href="https://www.who.int/teams/global-malaria-programme/case-management/diagnosis/rapid-diagnostic-tests">lateral-flow tests</a> which detect molecules from the parasite circulating in the blood. But <a href="https://malariajournal.biomedcentral.com/articles/10.1186/s12936-016-1508-y">some studies</a> suggest they may only be accurate 75% of the time. </p>
<p>The challenge therefore is to diagnose malaria with the sensitivity and accuracy of the PCR test, using the same simple equipment as the lateral flow test.</p>
<p>To do this, we’ve developed a unique “origami” diagnostic system. It is based on folded sheets of waxed paper and the process is known as loop-mediated isothermal amplification, or LAMP. This is similar to the established PCR test, but easier to use.</p>
<p>We use a common household printer to print patterns made from water-resistant wax onto paper. We melt the wax to the paper on a hotplate. Then, a <a href="https://phys.org/tags/blood+sample/">blood sample</a> taken from a patient via fingerprick is placed into a channel defined in the wax pattern. The fluids and regents move in the paper by capillary action (in much the same way as absorbent tissue soaks up a spillage). </p>
<p>Eventually the sample is transferred to three small chambers in a cartridge that integrates with the origami paper. The cartridge is placed into a purpose built 3D printed cassette, powered using a simple power source (such a mobile phone). It carries out the LAMP reaction to test the sample’s DNA for evidence of the disease-causing parasite. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/415676/original/file-20210811-23-1tcdnx6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/415676/original/file-20210811-23-1tcdnx6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/415676/original/file-20210811-23-1tcdnx6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/415676/original/file-20210811-23-1tcdnx6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/415676/original/file-20210811-23-1tcdnx6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/415676/original/file-20210811-23-1tcdnx6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/415676/original/file-20210811-23-1tcdnx6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The smartphone-enabled test uses paper folding, akin to ‘origami’, to carry out the complex reactions to detect malaria, a disease transmitted by mosquitoes, here represented in an origami design.</span>
<span class="attribution"><span class="source">Peter McKenna</span></span>
</figcaption>
</figure>
<p>Our origami system was field-tested at two primary schools in the Mayuge and Apac districts in Uganda. It correctly diagnosed malaria in 98% of the samples. Our finding was confirmed by testing the samples again using the PCR process. The results suggested that paper-based LAMP diagnostics could deliver better, faster, more effective malaria tests in communities. </p>
<p>But that still left us with the second WHO challenge to overcome: creating a digital system which local and national authorities could use to monitor infections.</p>
<h2>Mobile-phone based digital support</h2>
<p>We believe that Africa’s widespread adoption of smartphones, even in the most remote areas, could be key to empowering people to administer tests and securely share their results with health authorities.</p>
<p>Working with the Uganda Ministry of Health once more, we set out to develop a diagnostic app to pair with our origami diagnostic system. </p>
<p>We used blockchain technology to secure patient confidentiality. The technology ensures that only authorised healthcare workers with the correct “key” can access the results. And it traces all access and decisions securely.</p>
<p>The smartphone is paired with a 3D-printed stand containing a simple heating element. The phone provides the battery power to run the DNA based assay. The app controls the temperature of the origami test.</p>
<p>We also use the mobile phone to analyse the data and tell the healthcare professional what species of malaria the person is infected with. This ensures that the right drugs are correctly administered. Health workers don’t need to be highly skilled.</p>
<p>Results are securely stored on a blockchain-based ledger to ensure their privacy. They are wirelessly shared only with trusted organisations such as regional or nation health authorities. </p>
<p>In collaboration with local educational bodies, we partnered again with a Ugandan primary school to evaluate our new system in the real world. We tested blood samples from children aged between 5 and 12. Again, the results were 98% accurate.</p>
<p>The outcomes from those tests helped children who tested positive for malaria to get timely access to treatment. They’ve also been used by regional authorities to communicate information to central government ministries to inform local disease management strategies and interventions.</p>
<p>The sample size and geographical spread of our research was relatively small. But the technology has already had a positive effect on people’s lives.</p>
<h2>Looking ahead</h2>
<p>We’re planning to continue our work with the Ugandan government. By including new partners such as the Ugandan Industrial Research Institute, we will further develop our diagnostic system. We’ll explore industrial scale to make the prototype systems more widely available.</p>
<p>Ultimately, our hope is that we can give people in areas affected by malaria, no matter how remote, access to effective, easy-to-administer, secure tests. In doing so, we’ll also provide local health officials with new data to help better manage outbreaks as and when they occur. In the future, the systems we’ve developed could help tackle a range of other infectious diseases.</p><img src="https://counter.theconversation.com/content/165413/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jonathan Cooper has received funding from the UK Government Global Challenges Research Fund, RCUK and NIHR. </span></em></p><p class="fine-print"><em><span>Julien Reboud receives funding from the UK's Engineering and Physical Sciences Research Council, the National Institute of Health Research and the Scottish Funding Council. </span></em></p>We’ve made advances towards delivering new devices to empower even people with basic medical knowledge to administer malaria tests in the field.Jonathan Cooper, Wolfson Chair of Bioengineering (Biomedical Engineering), University of GlasgowJulien Reboud, Reader (Biomedical Engineering), University of GlasgowLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1601892021-05-16T07:50:46Z2021-05-16T07:50:46ZMalaria control needs longer lasting repellents. We’re a step closer to finding one<figure><img src="https://images.theconversation.com/files/400031/original/file-20210511-13-eh4lkx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Malaria infections can still occur outdoors.</span> <span class="attribution"><span class="source">GettyImages</span></span></figcaption></figure><p>Malaria is one of the <a href="https://www.who.int/news/item/09-12-2020-who-reveals-leading-causes-of-death-and-disability-worldwide-2000-2019">leading causes</a> of illness and death around the world. The disease is primarily caused by the bite of mosquitoes carrying a parasite. In 2019, around 229 million malaria <a href="https://www.who.int/news-room/fact-sheets/detail/malaria">cases were reported</a> with an estimated number of 409,000 deaths. Most of the reported cases occurred in sub-Saharan Africa. Children younger than five years and pregnant women are most prone to malaria. </p>
<p>To prevent malaria, the World Health Organisation (WHO) <a href="https://app.magicapp.org/#/guideline/4870">recommends</a> spraying insecticides indoors and using bed nets treated with long-lasting insecticide. </p>
<p>These interventions have one big flaw, however. They focus on minimising malaria infections indoors. Infections can still occur outdoors. And in some African countries <a href="https://www.nature.com/articles/nrdp201750">resistance to insecticides</a> – especially pyrethroids – is emerging. So new methods to control mosquitoes are needed urgently. </p>
<p>Numerous repellent-based products, such as creams, roll-ons and sprays, are available on the market for outdoor protection. Most of these have a very short period of protection – a few hours. People need to be protected from mosquito bites for longer.</p>
<p>To address this problem our <a href="https://malariajournal.biomedcentral.com/articles/10.1186/s12936-021-03681-7">research</a> project aims to <a href="https://www.sciencedirect.com/science/article/abs/pii/S1385894718324719">develop a new</a>, cost-effective product such as an anklet or bracelet to repel mosquitoes for an extended period. </p>
<p>A possible method of achieving this is to use polyolefin strands filled with mosquito repellents (DEET and icaridin). Polyolefins are the most extensively used group of thermoplastics polymers because of their strength, light weight, low cost, easy processability and good water barrier properties. This would make the total cost of the repellent-based product affordable. </p>
<h2>Our research</h2>
<p>Our project is a collaboration between the Institute of Applied Materials and the Institute for Sustainable Malaria Control at the University of Pretoria in South Africa alongside Martin Luther University Halle-Wittenberg in Germany and Eduardo Mondlane University in Mozambique. </p>
<p>In essence, we apply our skills in chemical and polymer technology to design and develop products that may help to reduce the malaria burden. </p>
<p>We’re trying a technology that releases chemicals from the plastic in a controlled way. We want the active ingredients of the mosquito repellent to emerge gradually and at the same concentration over a prolonged <a href="https://malariajournal.biomedcentral.com/articles/10.1186/s12936-021-03681-7">period of time</a>. </p>
<p>The polymer product acts as a reservoir for suitable repellents by trapping the active ingredients inside a polymer matrix. The release rate is controlled by a membrane-like structure at the surface of the <a href="https://www.sciencedirect.com/science/article/abs/pii/S1385894718324719">system</a>.</p>
<figure class="align-left ">
<img alt="Man sitting with his feet in a cage" src="https://images.theconversation.com/files/400018/original/file-20210511-23-1tij2p3.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/400018/original/file-20210511-23-1tij2p3.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=739&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400018/original/file-20210511-23-1tij2p3.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=739&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400018/original/file-20210511-23-1tij2p3.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=739&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400018/original/file-20210511-23-1tij2p3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=929&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400018/original/file-20210511-23-1tij2p3.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=929&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400018/original/file-20210511-23-1tij2p3.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=929&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A volunteer testing mosquito a repellant.</span>
<span class="attribution"><span class="source">author supplied</span></span>
</figcaption>
</figure>
<p>We tested the polymer strands filled with repellents – DEET and icaridin – over a period of 12 weeks. This means each repellent-polymer strand lasts 12 weeks. DEET is the key active ingredient in many commercial mosquito-repellent formulations. It is also an environment-friendly compound. Icaridin is also a safe and effective repellent that has been available for many years for mosquito application. We tested the strands under controlled conditions in an insectary to determine their activity against mosquitoes. Caged mosquitoes were offered the opportunity to feed on both treated and untreated body parts of human volunteers. Three hundred mosquitoes were placed in a large netting cage. The volunteers could put their legs into the cage through portals.</p>
<p>The test strand, 3 metres long, was wound around one leg of a volunteer, leaving the other leg fully exposed. Both legs were then inserted into the cage, one leg per entry hole, and the person stood still for five minutes. After five minutes two other people used flashlights to count the number of mosquitoes on the lower leg of the test person. The numbers of mosquitoes on the treated and untreated legs were recorded separately.</p>
<p>The result showed that most of the mosquitoes chose to feed on untreated legs. The novel repellent-based polymer product has a longer lifespan – 12 weeks more than commercially available repellents. It has the added benefit of not only repelling mosquitoes, but killing them too if they make contact with it. And the polyolefins are widely available and cost effective. This would make the final product affordable – an important consideration.</p>
<p>More extensive and rigorous entomological and epidemiological testing would have to be done on products like this before they could become commercially acceptable. </p>
<h2>Looking ahead</h2>
<p>Malaria cannot be eliminated by just one vector control method. An integrated multidisciplinary approach is needed. </p>
<p>New, safe and sustainable methods need to be researched and developed to overcome current resistance trends and prevent transmission of malaria from all angles.</p>
<p>Our research opens the door to a new mosquito repellent formulation that improves the armoury against malaria.</p><img src="https://counter.theconversation.com/content/160189/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>António Benjamim Mapossa does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>This project may help to eradicate malaria by developing new technologies to prevent mosquitoes from biting people when they are outdoors.António Benjamim Mapossa, Postdoctoral fellow in UP Institute for Sustainable Malaria Control (UP ISMC), University of PretoriaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1369762020-04-23T13:52:12Z2020-04-23T13:52:12ZMalaria still kills 1,100 a day. It can’t afford to lose resources to coronavirus<figure><img src="https://images.theconversation.com/files/332622/original/file-20200505-83775-1iba9rt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A woman holds a baby in her arms as she sits on a bed under a mosquito net in the Koumassi district of Abidjan. </span> <span class="attribution"><span class="source">Sia Kambou/AFP via Getty Images</span></span></figcaption></figure><p>Today, another <a href="https://www.who.int/news-room/fact-sheets/detail/malaria">1,100 people</a> will die from malaria. The number will be repeated tomorrow, and the day after. </p>
<p>As a public health researcher, I embrace the idea that all lives have equal value. That our goal is much more to delay death than to stop death, as the latter is inevitable. Therefore as we mark this year’s World Malaria Day, we must emphasise the need for <a href="https://endmalaria.org/news/strong-health-systems-and-sustained-investment-keys-reaching-zero-malaria">stronger health systems and sustained investments</a> to tackle malaria more aggressively. </p>
<p>This message needs to be conveyed even more urgently than usual amid the coronavirus pandemic. Given the situation in Europe, China and the US, <a href="https://www.nytimes.com/2020/04/22/world/coronavirus-live-news-updates.html">it is clear</a> that COVID-19 significantly disrupts health systems and economic growth. There is <a href="https://www.aljazeera.com/programmes/countingthecost/2020/04/africa-healthcare-system-cope-coronavirus-pandemic-200418125316241.html">genuine fear</a> that if it continues spreading in Africa, the impact may be worse given the continent’s weaker health systems. One of the greatest concerns is the likely shift of attention and resources from control programmes of other infections, such as malaria.</p>
<p>Since 2000, Africa has benefited from some of the greatest efforts against malaria. This included a global coalition that has delivered more than <a href="https://endmalaria.org/news/2-billion-mosquito-nets-delivered-worldwide-2004">2 billion insecticide-treated nets</a> to countries where malaria is endemic. </p>
<p>Given the extensive health gains, experts increasingly embraced the idea that malaria eradication, though ambitious, is <a href="https://www.thelancet.com/commissions/malaria-eradication">both a feasible and a necessary goal</a>. This remains the aim. </p>
<p>Recently, a strategic advisory panel set up by the World Health Organisation (WHO) five years ago released a report of a three-year study on <a href="https://www.who.int/publications-detail/malaria-eradication-benefits-future-scenarios-feasibility">benefits, future scenarios and feasibility of malaria elimination</a>. Among its key recommendations is improved access to high-quality people-centred health services, adequate financing and resourcing for malaria programmes as well as stronger engagement with communities. </p>
<p>Unfortunately, in the context of COVID-19, many of these recommendations will be unattainable in the short and medium term. Resources will be shifted to tackle the pandemic and community engagement initiatives will be reduced to a bare minimum to achieve social distancing. Moreover, access to health facilities may be reduced for people with other common diseases such as malaria.</p>
<p>This will mean there will be many more deaths from malaria and other diseases. </p>
<p>This has happened before. Evidence from Africa’s fight against Ebola suggests that during outbreaks, many more people are indirectly killed by other diseases such as <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4766886/">malaria, HIV and tuberculosis than by the outbreak itself</a>. </p>
<p>African health authorities must therefore earnestly guard against such outcomes, and create a more rational response.</p>
<h2>Protecting gains made against malaria</h2>
<p>The past 20 years have seen major scientific developments. These have led to malaria deaths being <a href="https://www.who.int/malaria/en/">cut from over 1 million to 405,000</a> a year.</p>
<p>This has been due in part to advances in treatments. Artemisinin-based treatments have replaced previous mono-therapies such as chloroquine. The new drugs have remained effective across Africa, which has largely been unaffected by treatment failures <a href="https://www.nejm.org/doi/full/10.1056/NEJMoa0808859">such as those observed in south-east Asia</a>. About 4 million doses of child formulations of these treatments <a href="https://www.mmv.org/our-impact/achievements/390-million-treatments-coartem-dispersible-delivered-over-50-countries">have been delivered</a>, saving another 850,000 lives.</p>
<p>There have also been advances in prevention measures. For example, to mitigate the threat of insecticide resistance in malaria mosquitoes, scientists from private and public institutions have created <a href="https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD012776.pub2/abstract">new types of insecticidal bed nets</a> and <a href="https://www.who.int/pq-vector-control/prequalified-lists/en/">new chemical formulations for spraying houses</a>. And countries such as Tanzania are using <a href="https://malariajournal.biomedcentral.com/articles/10.1186/s12936-020-03222-8">innovative distribution approaches involving schools</a> so that they can maintain high coverage and access to essential malaria commodities.</p>
<p>But African countries don’t have <a href="https://www.project-syndicate.org/commentary/malaria-prevention-mosquito-nets-not-enough-by-fredros-okumu-2019-04?barrier=accesspaylog">resilient communities and strong health systems</a>. This means that these past gains need to be protected vigorously.</p>
<h2>Not all fevers are COVID-19</h2>
<p>Initial symptoms of malaria – such as a high fever – may be similar to those of influenza and other viral infections such as COVID-19. </p>
<p>This underscores the need for malaria programme managers, community leaders and health workers in affected communities to continue to emphasise prompt diagnosis, effective treatment and improved prevention. But health workers and communities should not be put at any risk. Therefore essential information should be provided about both malaria and COVID-19.</p>
<p>In addition, special efforts will need to be made to avert indirect deaths. For example during the Ebola outbreak, <a href="https://link.springer.com/article/10.1186/s12936-016-1493-1">a mass drug rollout</a> was put in place in Sierra Leone to prevent malaria deaths. </p>
<p>Similarly, countries will require innovative approaches to ensure continued distribution of insecticide treated nets. The WHO has already sent an <a href="https://www.who.int/malaria/publications/atoz/tailoring-malaria-interventions-in-the-covid-19-response/en/">advisory to malaria-endemic countries</a> on how to tailor their control efforts during the COVID-19 pandemic. Without this, Africa will bear the combined consequences of both diseases.</p>
<p>Since <a href="https://zeromalaria.africa/">zero malaria starts with each one of us</a>, we must keep up the malaria fight through this cloud of COVID-19.</p><img src="https://counter.theconversation.com/content/136976/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Fredros Okumu is a World Economic Forum Young Global Leader. He receives research funding from the Bill & Melinda Gates Foundation; Wellcome Trust; and Royal Society, London. </span></em></p>If not addressed, there will be many more deaths from malaria and other diseases, indirectly linked to COVID-19 disruptions.Fredros Okumu, Director of Science, Ifakara Health InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/875302017-12-14T17:39:20Z2017-12-14T17:39:20ZPeople stay vigilant to the threat of malaria, even when infections fall<figure><img src="https://images.theconversation.com/files/198118/original/file-20171207-28921-i5c6y8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Karen Kasmauski/MCSP)</span></span></figcaption></figure><p>Since the turn of the century great strides have been made to reduce the burden of malaria in sub-Saharan Africa. But the disease, spread by the Anopheles mosquito, still remains a major threat: in 2015 there were an estimated 212 million cases worldwide, according to the most recent <a href="http://www.who.int/malaria/publications/world-malaria-report-2016/report/en/">World Malaria Report</a>. </p>
<p>Malaria can be prevented in several ways, in particular by sleeping under an insecticide-treated bed net and spraying homes with an insecticide. </p>
<p>Bed nets are a commonly used prevention method while indoor residual spraying is only done in specific high risk areas. In 2015, about 53% of the at-risk population in sub-Saharan Africa <a href="http://www.who.int/malaria/publications/world-malaria-report-2016/report/en/">slept under an insecticide treated net</a>. In the same period, 3.1% of the population at risk of contracting malaria in the region had their homes protected. </p>
<p>Bed nets are distributed through mass campaigns and at antenatal and child vaccination clinics. But of course people can decide not to use the nets, even if they receive one. Indoor residual spraying on the other hand is a public intervention carried out by national governments with the help of international organisations. </p>
<p><a href="https://hal-pjse.archives-ouvertes.fr/halshs-00911364/document">Our study</a> explores the effect of malaria risk in the area and of indoor residual spraying on individual decision to use bed nets. We focus on nine countries in sub-Saharan Africa in which malaria is endemic: Angola, Burundi, Cameroon, Liberia, Madagascar, Malawi, Mozambique, Tanzania and Uganda. Our data combines information on household behaviours and characteristics from <a href="http://dhsprogram.com/">the Demographic and Health Survey data</a> with information on malaria prevalence from <a href="http://www.map.ox.ac.uk/">the Malaria Atlas Project</a>.</p>
<h2>An eradication plan</h2>
<p>The World Health Organisation has set an ambitious goal of controlling and eradicating the disease by 2030. This includes reducing malaria cases and mortality rates by at least 90% and eliminating malaria in at least 35 countries by 2030.</p>
<p>But for eradication campaigns to be successful the relationships between malaria prevalence, indoor residual spraying and individual bed net usage are crucial. </p>
<p>Numerous studies have evaluated the effectiveness of bed nets and indoor residual spraying as malaria prevention interventions. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/198123/original/file-20171207-28958-nth8cd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/198123/original/file-20171207-28958-nth8cd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/198123/original/file-20171207-28958-nth8cd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/198123/original/file-20171207-28958-nth8cd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/198123/original/file-20171207-28958-nth8cd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/198123/original/file-20171207-28958-nth8cd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/198123/original/file-20171207-28958-nth8cd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A worker prepares a canister for internal residual spraying to prevent malaria in a high risk area in Ethiopia.</span>
<span class="attribution"><span class="source">flickr/USAID</span></span>
</figcaption>
</figure>
<p>But there are two points that may have been overlooked. The first is whether the risk of getting malaria – malaria prevalence in the area – has any effect on individual bed net usage. The second is whether bed nets are used in houses that are covered by an indoor residual spraying programme. </p>
<p>Our study investigates these two questions. Firstly, we ask whether the risk of being infected in an area influences people to use their bed nets. When the prevalence of the disease decreases in the area, does bed net usage decrease proportionally or more than proportionally? </p>
<p>Secondly, we investigate what effect spraying has on people using the nets: do people substitute the nets with spraying? Does a publicly provided intervention reduce the likelihood of people using the nets?</p>
<p>In most regions, bed nets are the main tool in the fight against malaria. If people are using bed nets less because they no longer see malaria as a threat, eradicating the disease may become impossible.</p>
<p>Our results show that as malaria prevalence falls, people reduce their bed net usage. Spraying does not reduce the proportion of people who chose to use a bed net. In fact, spraying increases the use of bed nets. </p>
<h2>A clear message</h2>
<p>One possible explanation for the increased use is that as governments and organisations go through houses spraying the insecticide, the households receive the message – either explicitly or implicitly – that malaria is a real threat and that one should do what they can to prevent it.</p>
<p>Individual responses to malaria risk and spraying programmes mean that international efforts to control the disease will not be hampered, as is feared. And it means that the global health community can continue its quest to eradicate malaria in the next 13 years.</p><img src="https://counter.theconversation.com/content/87530/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gabriel Picone receives funding from the Fogarty International Center for this project.</span></em></p><p class="fine-print"><em><span>Bénédicte Apouey received funding from the Fogarty International Center -- a branch of the United States government's National Institutes of Health -- for this project.</span></em></p><p class="fine-print"><em><span>Robyn Kibler does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>When there are two malaria prevention interventions available people don’t take an either or approach – they consider that the two interventions are complementary.Gabriel Picone, Professor in the Department of Economics, University of South FloridaBénédicte Apouey, Chercheuse en sciences sociales au CNRS, Paris School of Economics – École d'économie de ParisRobyn Kibler, Postdoctoral Researcher, University of South FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/863552017-11-22T12:17:49Z2017-11-22T12:17:49ZHow drones are being used in Zanzibar’s fight against malaria<figure><img src="https://images.theconversation.com/files/195789/original/file-20171122-6013-yq6uu8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Makame Makame from the Zanzibar Malaria Elimination Programme holds one of the drones used to map malaria vectors.</span> <span class="attribution"><span class="source">Andy Hardy</span></span></figcaption></figure><p>On a typically hot and humid July day in Stonetown, the capital of Zanzibar, a gaggle of children, teenagers and the odd parents watched our small drone take flight. My colleagues Makame Makame, Khamis Haji and I had finally found the perfect launch spot.</p>
<p>With a high-pitched humming, the drone took to the air. It sounded like a big mosquito – appropriate, since we were testing the use of drones for mapping aquatic malaria habitats. These shallow sunlit water bodies teem with mosquito larvae. In a matter of days, the larvae will emerge as adult mosquitoes in search of a blood meal. If one of those mosquitoes bites a human infected with malaria, it will become a vector for the disease and continue its deadly transmission cycle.</p>
<p>Zanzibar is a Tanzanian archipelago off the coast of East Africa. Both it and mainland Tanzania have fought a long, well documented battle with malaria. <a href="http://www.who.int/gho/malaria/epidemic/deaths/en/">Globally</a>, the disease infects over 200 million people annually and is responsible for killing approximately 500,000 people each year.</p>
<p>The <a href="http://www.who.int/topics/millennium_development_goals/diseases/en/">Millennium Development Goals</a> prompted a number of large scale campaigns across sub-Saharan Africa to combat malaria. <a href="https://www.cdc.gov/malaria/malaria_worldwide/reduction/itn.html">Millions of bed nets</a> were distributed. Insecticide was supplied to spray in homes across communities. The aim was to stop people getting bitten, interrupting the transmission cycle. </p>
<p>It’s been a real success story, leading to a notable decrease in the disease’s prevalence. Some areas of Zanzibar have seen <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3639098/">prevalence levels drop</a> from 40% of the population having malaria to less than 1%.</p>
<p>Now epidemiologists and public health managers are looking to complement indoor-based nets and spraying with outdoor based solutions. In effect, they’re taking the battle to mosquitoes. And drones are a crucial part of their armoury. One of the main challenges to disease managers is finding small water bodies that mosquitoes use to breed. This is where drones come in – for the first time, drone imagery can be captured over large areas which can be used to create precise and accurate maps of potential habitats.</p>
<h2>Tracking mosquitoes</h2>
<p>We <a href="https://www.cdc.gov/malaria/about/biology/mosquitoes/">know</a> that once an adult mosquito has fed and rested, it will typically go in search of a mate. Then it moves on to a suitable location – an aquatic habitat like the fringes of river channels, roadside culverts and irrigated rice paddies – to lay its eggs.</p>
<p>Public health authorities need to be able to locate and map these water bodies so they can be treated using a larvicide like DDT. This process is known as larval source management, and was successfully used in Brazil and Italy many decades ago. There, the DDT killed mosquito larvae – but could also be <a href="http://www.sciencedirect.com/science/article/pii/S0169475899016051">devastating</a> for local ecology as well as having adverse effects on human health.</p>
<p>Today much safer, low toxicity replacements have been developed. The problem is that they come at a cost. Resources are also needed to disseminate the larvicide and to locate the water bodies that host the mosquito eggs and larvae. Some of these hideaways are tough to find on foot, and if water bodies are accurately mapped a larvicide campaign could end up being a waste of time.</p>
<p>My institution, <a href="https://www.aber.ac.uk/en/dges/staff-profiles/listing/profile/ajh13">Aberystwyth University</a> in Wales, is working with the Zanzibar Malaria Elimination Programme to fly drones over known malaria hot spots. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/192794/original/file-20171101-19858-1muno94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/192794/original/file-20171101-19858-1muno94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/192794/original/file-20171101-19858-1muno94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=357&fit=crop&dpr=1 600w, https://images.theconversation.com/files/192794/original/file-20171101-19858-1muno94.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=357&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/192794/original/file-20171101-19858-1muno94.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=357&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/192794/original/file-20171101-19858-1muno94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=449&fit=crop&dpr=1 754w, https://images.theconversation.com/files/192794/original/file-20171101-19858-1muno94.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=449&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/192794/original/file-20171101-19858-1muno94.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=449&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A rice paddy in Mwera, Zanzibar. These and other watery sites are perfect spots for mosquitoes to lay their eggs.</span>
<span class="attribution"><span class="source">Image collected by Andy Hardy using a DJI Phantom 3 drone.</span></span>
</figcaption>
</figure>
<p>In 20 minutes, a single drone is able to survey a 30 hectare rice paddy. This imagery can be processed and analysed on the same afternoon to locate and map water bodies. This has proved to be highly accurate and efficient. This is all using one of the most popular off-the-shelf drones, the Phantom 3 made by DJI. These are about the size of a shoebox, weighing a little more than a bag of sugar (1.2 kg) and are used throughout the world for both leisure and commercial photography.</p>
<p>We started off working in test locations across Zanzibar but now, with the support of the <a href="http://www.ivcc.com/">Innovative Vector Control Consortium</a> – a non-for-profit partnership aiming to create novel solutions for preventing disease transmission – we’re widening our range to explore how this technology can be incorporated into operational malaria eliminating activities.</p>
<p>It doesn’t stop there. We plan to incorporate the drone imagery into smartphone technology to help guide larvicide spraying teams to water bodies on the ground, and to track their progress and coverage. There’s also an exciting drive towards automatically disseminating larvicide from the drones themselves.</p>
<h2>Getting people involved</h2>
<p>Despite these exciting advances, operators need to be mindful of the negative side of drones: invasion of privacy; collisions with aircraft and birdlife; their association with warfare. These are very real concerns for the public.</p>
<p>In Zanzibar, we worked alongside village elders to show them the drones and explain exactly what we plan to use them for. We also encouraged people to gather around when we were looking at live-feed footage from the drone’s onboard camera. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/-pkmgpcNXFg?wmode=transparent&start=59" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Collation of drone imagery recorded using a DJI Phantom 3 over a range of sites across Zanzibar.</span></figcaption>
</figure>
<p>This introduced people to our work and gave them a chance to see how drones and similar technologies, used alongside traditional indoor-based interventions, can really help to make malaria elimination in their community a reality.</p><img src="https://counter.theconversation.com/content/86355/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andy Hardy receives funding from the UK Natural Environment Research Council, the UK Space Agency and the Innovative Vector Control Consortium. </span></em></p>Epidemiologists and public health managers are looking to complement indoor-based malaria solutions with those that focus on the outdoors. Drones are a crucial part of their armoury.Andy Hardy, Lecturer in Remote Sensing and GIS, Aberystwyth UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/870202017-11-14T13:27:52Z2017-11-14T13:27:52ZSouthern Africa is slipping again after coming close to eliminating malaria<figure><img src="https://images.theconversation.com/files/194542/original/file-20171114-27625-6lfukr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Brant Stewart/RTI</span></span></figcaption></figure><p><em>In the last five years, South Africa, Botswana, Namibia and Swaziland have all been on the verge of eliminating malaria. In fact, progress had been so good that the southern African region had been tipped to be malaria free by 2018. But a spike in cases this year means that it’s unlikely to meet the target. A new target has been set for 2020. The Conversation Africa’s Health and Medicine editor Candice Bailey asked Professor Rajendra Maharaj to explain why.</em></p>
<p><strong>Why has there been a spike in malaria cases in southern Africa? Is it unusual?</strong></p>
<p>Over the last few years there has been a downward trend in the number of malaria cases globally. There was a <a href="https://theconversation.com/parts-of-southern-africa-are-within-tantalising-reach-of-eliminating-malaria-49848">marked decrease in cases</a> in South Africa and in several other countries in the region including Swaziland, Botswana and Namibia. This trend was so encouraging that the region had become comfortable with the idea that it would reach the target of eliminating malaria by 2018. South Africa, for example, experienced a serious epidemic in the 1999/2000 malaria season where over 62 000 cases were recorded but with reinforced interventions, the cases decreased to under 5 000 in 2016.</p>
<p>The countries in the region achieved this by implementing evidence-based indoor residual programmes and improving diagnostics and treatment, introducing artemisinin-based combination therapy.</p>
<p>But this year <a href="http://www.nicd.ac.za/index.php/update-malaria/">figures</a> in some parts of South Africa were triple what they were last year. The reality is that in only some parts of the country will we have eliminated malaria. Although the number of cases reported from KwaZulu-Natal increased, it’s still possible to reach the 2020 goal but the same can’t be said for Mpumalanga and Limpopo. These two areas receive many imported cases from Mozambique and Zimbabwe. </p>
<p>This spike is not restricted to South Africa. It has happened in all <a href="http://www.nicd.ac.za/index.php/malaria-advisory-april-2017/">southern African countries</a>. But the increase has been the greatest in Namibia and Swaziland.</p>
<p>We have yet to confirm what caused the spike in the region. We know that the mild winter conditions created fertile ground for mosquito breeding. But we still need to understand what’s behind the increase in cases so that we can tackle the problem. </p>
<p>There are many questions. For example, was there a failure in the case management? Was there a relaxed attitude to implementing all the planned interventions? We still need to answer these questions. There are several possible reasons for the spike.</p>
<p>One possibility is the sub-optimal insecticide spray coverage contributed to the increased transmission. Another is the Malaria Control Programme was ill prepared for the epidemic. At one point this year there was as shortage of drugs in the province and these had to brought in as a matter of urgency after the epidemic struck. </p>
<p>A third possibility is that with heavy rains preceding a very dry period, there were many suitable pools for breeding and the hot conditions were ideal for mosquito breeding.</p>
<p><strong>How does the region handle malaria control currently. Are there weaknesses in the strategy?</strong></p>
<p>To control malaria, countries in the region use one of two strategies: <a href="http://apps.who.int/iris/bitstream/10665/177242/1/9789241508940_eng.pdf?ua=1&ua=1">indoor residual spraying</a> (IRS) and the use of <a href="http://www.who.int/mediacentre/factsheets/fs094/en/">Long-lasting Insecticide Treated Nets</a> (LLINs). These are either used in isolation or as part of an integrated programme. South Africa uses indoor residual spraying and little larval control measures that targets the breeding sites of mosquitoes. In Swaziland, Botswana and Namibia the focus has been on indoor spraying but net coverage has achieved high levels in these countries. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/194533/original/file-20171114-27576-2q1xcw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/194533/original/file-20171114-27576-2q1xcw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/194533/original/file-20171114-27576-2q1xcw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/194533/original/file-20171114-27576-2q1xcw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/194533/original/file-20171114-27576-2q1xcw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/194533/original/file-20171114-27576-2q1xcw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/194533/original/file-20171114-27576-2q1xcw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">e f b z.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/usaid_images/8720623278/in/photolist-ehBttL-ktf152-aLqs2z-ehBHes-djKSj7-ihPrTc-djKPuy-djKRVS-b2Ny-a9HWsi-djLCYw-djKQDa-djLC2R-djKSqW-djKQkw-a9HWqt-djLBPv-4WNzs8-djLDc7-djKRLh-a9HWnp-4eGFuv-djLBff-bBV1gw-4WWzeo-4oLZhA-e4pxqP-e4v9kd-djLBHy-djLBnV-e4v9Bf-e4pxmp-djKPXm-fM26KC-djKQ7Y-e4px6a-djKPMB-8epoks-PCRVkh-PYNcgA-8aWBAw-cEWd6J-9F6YgH-5CqSWZ-zriZB-aadUW7-xwvXaf-LTeexd-GYQjQC-HKWsQb">USAID/flickr</a></span>
</figcaption>
</figure>
<p>The World Health Organisation <a href="http://www.who.int/heli/risks/vectors/malariacontrol/en/index6.html">recommends</a> the use of integrated mosquito control where more than one method is used.</p>
<p><strong>What are the other challenges in controlling malaria in the region? And why does the focus need to change?</strong></p>
<p>The region’s most powerful and effective vector control strategy has been spraying houses with the powerful insecticide DDT through the indoor residual spraying. But the impact of indoor residual spraying is often diluted due of <a href="http://www.who.int/malaria/publications/atoz/insecticide-resistance-implications/en/">insecticide resistance</a> to the currently used insecticides. Insecticides should be used on a rotational basis or in a mosaic spray pattern to mitigate resistance developing.</p>
<p>In areas where there’s been high levels of transmission, it was found that the spray coverage for insecticides recommended by the World Health Organisation wasn’t optimal. It’s <a href="http://apps.who.int/iris/bitstream/10665/177242/1/9789241508940_eng.pdf?ua=1&ua=1">recommendation</a> is that 80% of the houses in a malaria infected community should be sprayed. But the region is not achieving this coverage.</p>
<p>Another cause for concern is that there are an increasing number of people refusing to have their homes sprayed with insecticide. This may be due to a lack of awareness of the need to have the houses sprayed. The reasons for this are unclear, but its suspected to be linked to the disease burden being low. </p>
<p>Participating in the indoor residual spraying programme is purely voluntary. People can’t be forced to have their homes sprayed as there is no legislation in place to compel them to have their houses sprayed. If people refuse, there’s nothing that can be done except to educate the homeowner to gain permission to spray. </p>
<p><a href="http://www.who.int/heli/risks/vectors/malariacontrol/en/index6.html">DDT</a> is the cheapest insecticide. It has a long residual life on the market and as a result countries with limited resources use it as a tool to control vectors. There is very little resistance to DDT in the region but there is enormous political pressure to move away from using DDT.
What is needed in these countries are robust public awareness campaigns informing people that, even when there have the is no disease, malaria can resurge as long as there are vector mosquitoes in the area. </p>
<p>There is evidence from developing countries in other parts of the world that elimination can be achieved. Sri Lanka is the latest country to <a href="http://www.searo.who.int/mediacentre/releases/2016/1631/en/">achieve elimination</a>. They had a very strong vector control programme that succeeded in reducing the caseload significantly. Once this was achieved proper case management further reduced the case numbers. </p>
<p>And when there were no local cases an intensive surveillance programme was implemented. Although elimination was achieved, entomological surveillance and disease surveillance was strengthened.</p><img src="https://counter.theconversation.com/content/87020/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rajendra Maharaj does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A spike in the number of malaria cases in southern Africa means that the region will not meet its initial target of eliminating malaria by 2018.Rajendra Maharaj, Unit Director of the Office of Malaria Research , South African Medical Research CouncilLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/765262017-04-24T15:59:28Z2017-04-24T15:59:28ZWhat Africa still needs to do to eliminate malaria<figure><img src="https://images.theconversation.com/files/166535/original/file-20170424-12658-wbnpmz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A young girl with malaria rests in the inpatient ward of a health centre in the South Sudan. </span> <span class="attribution"><span class="source">Reuters/Adriane Ohanesian </span></span></figcaption></figure><p>Malaria is one of the oldest and <a href="http://www.planet-science.com/categories/over-11s/human-body/2012/03/malaria---the-deadliest-parasitic-disease-on-the-planet.aspx">deadliest</a> infectious diseases affecting man. It is an ancient and modern disease – descriptions of illnesses similar to malaria are found in <a href="http://www.sciencedirect.com/science/article/pii/S0020751916301229">ancient texts</a> from China, India, the Middle East, Africa and Europe. </p>
<p>Malaria parasites have <a href="http://www.sciencedirect.com/science/article/pii/S0020751916301229">co-evolved</a> – which involves genetic changes and adaptation – with people as their hosts over a period of four thousand years. </p>
<p>After the Second World War, the <a href="http://www.who.int/bulletin/volumes/86/2/07-050633/en/">Global Malaria Eradication Programme</a> was intensified by the discovery of <a href="https://www.aei.org/publication/the-rise-fall-rise-and-imminent-fall-of-ddt/">DDT</a>, a powerful pesticide. The campaign partially reduced the malaria transmission cycle and infection rates within a short time.</p>
<p>The US eradicated malaria by <a href="http://www.the-scientist.com/?articles.view/articleNo/29069/title/US-Malaria-Deaths--1870/">1951</a> but in <a href="http://www.isid.ac.in/%7Etridip/Teaching/DevelopmentMicroeconomics/Spring2012/Readings/03Health/07Bleakley-AEJAE2010.pdf">Latin and South America</a> pockets recurred two decades later. </p>
<p>Today malaria has been eliminated in <a href="http://www.who.int/malaria/areas/elimination/overview/en/">26 other countries</a> including Cuba, Italy and Japan. About 65 countries are planning to eradicate the disease between 2020 and 2030.</p>
<p>Africa carries a disproportionately high burden of malaria cases. In 2015 <a href="http://apps.who.int/iris/bitstream/10665/252038/1/9789241511711-eng.pdf?ua=1">214 million</a> people across the world were infected with malaria leading to about 430 000 deaths. Of these, 90% occurred in Africa. And two countries on the continent, Nigeria and the Democratic Republic of Congo, accounted for more than 35% of global malaria deaths.</p>
<p>There has been some improvement. Between 2010 and 2015 there was a 21% reduction of malaria cases reported on the continent, and a 31% reduction in number of deaths. </p>
<p>But Africa needs to urgently put a number of additional measures in place to speed up these advances, and to move towards eliminating the disease. These include accelerated investment and deployment of vaccines, new diagnostic tools, new funding strategies for malaria control and keeping in check the drug and insecticide resistance challenge.</p>
<p>Funding is also key if African countries are going to move closer to eradication. Evidence shows that eliminating malaria in Africa has been weakened by the <a href="https://malariajournal.biomedcentral.com/articles/10.1186/s12936-016-1171-3">lack of sustained funds</a>. </p>
<h2>What’s made a difference, where the problems lie</h2>
<p>The following major investments in the last one and a half decades have led to the incidents of malaria declining:</p>
<ul>
<li><p>Insecticide treated bed nets </p></li>
<li><p>effective antimalarial medicines</p></li>
<li><p>indoor residual spraying</p></li>
</ul>
<p>These are the cornerstones of effective malaria control. But there are a few hurdles that threaten their usefulness. These include:</p>
<ul>
<li><p>drug and insecticide resistance</p></li>
<li><p>the quality of antigen based rapid diagnostic malaria test kits. They do not <a href="https://malariajournal.biomedcentral.com/articles/10.1186/s12936-016-1450-z">detect</a> sub-microscopic levels of malaria parasites.</p></li>
</ul>
<p>In addition, malnourished children do not <a href="http://aac.asm.org/content/57/12/5792.full">absorb</a> antimalarial medicines sufficiently to obtain levels in the blood stream that effectively kill the parasites.</p>
<p>It’s clear that more potent interventions are urgently needed. Investment in accelerated development and introduction of vaccines should be prioritised. A <a href="http://www.malariavaccine.org/malaria-and-vaccines/first-generation-vaccine/rtss">malaria vaccine</a> candidate that is currently under trial in Africa, RTSS, has shown a modest 39% efficacy. It has also shown promise with a prediction that in fully immunised children it can avert <a href="https://www.ncbi.nlm.nih.gov/pubmed/26549466">484 deaths per 100,000</a>.</p>
<p>On top of this, more funding needs to be made available as it has a direct impact on the ability of countries to bring malaria under control. For example, in <a href="http://www.cddep.org/tool/malaria_rates_zanzibar_rise_and_fall_funding_levels">Zanzibar</a> the malaria rates rose and fell with funding levels between 1960 and 2013. </p>
<p>Between 1981 and 1983 <a href="http://cgsd.columbia.edu/files/2012/11/STP-Elimination.pdf">Sao Tome</a> reported no malaria cases due to consistent indoor residual spraying of households with DDT twice a year and and weekly administration of drugs to prevent the disease. When the funding dried up, a major epidemic occurred in 1985 and by 1997 malaria prevalence had risen to 53%. </p>
<p>Sao Tome has recovered to the point that it is now in the <a href="http://www.undp.org/content/undp/en/home/presscenter/pressreleases/2016/02/15/end-of-malaria-in-sight-for-s-o-tom-and-pr-ncipe.html">pre-elimination</a> phase. With the current low transmission rates, the end of malaria could be in sight with the annual incidence dropping from 33.8 per 1,000 people in 2009 to 9.7 per 1000 in 2014. </p>
<p>In Kenya, transmission in the <a href="https://bmcinfectdis.biomedcentral.com/articles/10.1186/1471-2334-10-283">highlands of western Kenya</a> was reduced for between 2007 to 2008. This was <a href="https://malariajournal.biomedcentral.com/articles/10.1186/1475-2875-6-72">attributed</a> to widespread indoor residual spraying and the introduction of artemisinin based combination medicines with support from the Global Fund. </p>
<h2>Challenges facing Africa</h2>
<p>Among the key challenges facing Africa in malaria elimination are:</p>
<p><strong>Infrastructure challenges</strong>: weak health systems, resources like manpower, inaccessibility to malaria control services and poor surveillance systems are to blame for a weak roll out during the implementation phase. Health systems are under-resourced and poorly accessible to those most at risk. In 2015, a <a href="http://www.who.int/mediacentre/news/releases/2016/malaria-control-africa/en/">large proportion</a> (36%) of children with a fever were not taken to a health facility for care in 23 African countries. </p>
<p><strong>Drug resistance:</strong> it’s worrying that signs of resistance to artemesinin has been reported in about <a href="https://malariaworld.org/blogs/pierre-lutgen">12</a> African countries. This follows the rapid spread of drug resistance first reported in the greater <a href="https://www.ncbi.nlm.nih.gov/pubmed/24159830">Mekong region</a> in south East Asia. </p>
<p><strong>Insecticide resistance:</strong> since 2010, <a href="https://malariajournal.biomedcentral.com/articles/10.1186/s12936-017-1799-7">60 of the 73</a> countries that monitor insecticide resistance have reported mosquito resistance to at least one insecticide class used in nets and indoor spraying. From these samples, 50 reported resistance to two or more insecticide classes. </p>
<h2>The way forward</h2>
<p>To achieve low transmission rates and eventual elimination, African countries need to invest in understanding the geography, evolutionary history of flora and fauna, infrastructure and land use in Africa. An analysis into the eradication of malaria historically found that by understanding and addressing these factors, malaria control can be <a href="http://www.earth.columbia.edu/sitefiles/file/about/director/pubs/002.pdf">more successful</a>.</p>
<p>In addition, African countries need to diversify financing of malaria control. The initiatives should be cost effective to ensure they are accessible and evenly rolled out even in the continent’s poor resource regions.</p>
<p>And a national health financing strategy and road map to universal health coverage should be developed and implemented in sub-Saharan countries with a high burden of malaria. </p>
<p>All partners from the public and private sector, the civil society, development partners and the community should be involved. One of the reasons that community involvement is important is because it encourages ownership which leads to credible data which in turn makes it possible to monitor progress.</p>
<p>Africa has unfinished business before it achieves the aspirational theme of World Malaria Day – “End Malaria for good”. Robust investment and new malaria control tools are urgently needed to propel countries towards eliminating the disease.</p><img src="https://counter.theconversation.com/content/76526/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Willis Simon Akhwale does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Eliminating malaria in Africa has been held back by a range of factors, including a lack of funds and drug and insecticide resistance challenges.Willis Simon Akhwale, Country Director I-TECH Kenya, University of WashingtonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/621262016-07-11T21:05:42Z2016-07-11T21:05:42ZMalaria: should we abandon insecticide-treated bednets?<figure><img src="https://images.theconversation.com/files/129884/original/image-20160708-24079-myanab.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/dl2_lim.mhtml?src=aameXJdcHLkf3zd2yjPLdA-2-3&clicksrc=download_btn_inline&id=286728137&size=medium_jpg&submit_jpg=">punghi/Shutterstock</a></span></figcaption></figure><p>In Africa, some malaria-carrying mosquitoes have found ways to survive exposure to insecticides. This means that bednets treated with these chemicals may become less effective at preventing malaria. A new study we’ve published in <a href="http://www.pnas.org/content/early/2016/07/05/1603431113.abstract">PNAS</a> shows that although these resistant mosquitoes don’t die immediately on contact with insecticide-treated bednets, their risk of death in the days and weeks following contact is greatly increased. As a result, the opportunity for these mosquitoes to transmit malaria to a human drops by two-thirds.</p>
<p>There were over 200m cases of malaria in <a href="http://www.who.int/malaria/media/world-malaria-report-2015/en/">2015</a>, causing more than 400,000 deaths, mostly in Africa. While these numbers are still shockingly high, <a href="http://www.nature.com/nature/journal/v526/n7572/abs/nature15535.html">since 2000</a>, the rates of malaria have been decreasing dramatically, largely due to the widespread use of insecticide-treated bednets.</p>
<p>Such bednets help control malaria in two different ways: by providing a physical barrier between the human and the disease infected mosquito; or by turning the person sleeping under the bednet into a deadly mosquito trap, where the mosquito is lured towards the scent of the sleeper. The mosquito then flies into a wall of insecticide that not only stops it from biting but kills it too. So impregnating bednets with insecticide has been very useful for controlling malaria mosquito populations.</p>
<p>The problem with the widespread use of insecticide-treated bednets is that many mosquitoes have now become highly resistant to these chemicals. Insecticides are designed to kill mosquitoes immediately on contact, so when more than 10% of them are still alive in the day following exposure we know they are getting resistant to insecticides. </p>
<p>To worsen the problem, there is only one type of insecticide that can be safely used to treat bednets. So when mosquitoes become fully resistant, we could enter an era where our primary weapon against malaria can no longer be used and the public health gains achieved so far reversed.</p>
<h2>Thinking beyond 24 hours</h2>
<p>While the spread of insecticide resistance is of great concern, our results indicate that by classifying mosquitoes as resistant only on the basis of mosquito survival in the 24 hours following exposure, we are overseeing important long-term costs arising from exposure to insecticides. By rearing thousands of mosquitoes in the laboratory and exposing them to nets impregnated with insecticides we were able to closely monitor the longer-term fate of resistant mosquitoes that encounter an insecticide-treated bednet. We found that while they survive the first day, there were consistent reductions in their daily survival for the rest of their lives. Over the life time of the mosquito, these small but consistent reductions combine to reduce their lifespan by half. </p>
<p>The malaria parasites needs at least nine days to mature inside the mosquito before they can be passed onto a human, so these longer-term survival reductions could have a big impact on malaria transmission. </p>
<p>In total, we estimated that contact with a treated bednet can reduce the transmission potential of even highly resistant mosquitoes by two-thirds. This may explain why bednets appear to be effectively controlling malaria in areas of Africa where mosquito populations are highly resistant. So for now, it would be premature to abandon this strategy.</p>
<p>Unfortunately, we also found evidence that these longer-term impacts on mosquito survival may be temporary and could disappear as mosquitoes develop more intense levels of resistance. This is why there remains a huge urgency to find alternative methods to control malaria mosquitoes. </p>
<p>By making new insecticidal products - or finding alternative or other complementary solutions - we may be able to start killing these resistant mosquitoes again. As we wait for these developments, we should continue to use mosquito insecticide-treated bednets. Despite the rapid spread of insecticide resistance, they are still the most effective method to prevent malaria transmission.</p><img src="https://counter.theconversation.com/content/62126/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mafalda Viana receives funding from MRC. </span></em></p><p class="fine-print"><em><span>Angela Hughes does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Bednet insecticides should kill mosquitoes on contact, but some have become highly resistant to the chemicals.Mafalda Viana, Research fellow, University of GlasgowAngela Hughes, Laboratory Manager/PhD studentLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/577862016-04-26T04:26:52Z2016-04-26T04:26:52ZWhy individual Nigerians carry the heaviest malaria cost burden in Africa<figure><img src="https://images.theconversation.com/files/119874/original/image-20160422-17371-fa5r6r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A Nigerian woman purchases a mosquito net from a medical supply vendor. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/worldbank/7826365538/in/photolist-65bBch-cVAaNS-5xQN53-cVA9nq-hNsevL-cVA5ou-cVzYEs-7XPCT4-7Zi1gw-cVzXPU-7XDo5U-eQ1sBw-7XDnVs-7Zf3VZ-bBhMjm-cVzZUo-7ZeuSt-7ZetsF-7XSWuo-7ZexQk-7XA9iX-7XDo3q-7ZhQSN-7XDnRN-hNstE6-7ZhWME-hNrn3H-7XA986-hNrjfi-7ZhPSA-bQcpnH-hNrNTS-7XDnYu-hNsdsy-jKj3rk-bBhMzq-dhQxua-bQcoZT-8rbVaq-8r8Njr-7ZhJp9-7XA8Xa-bQcrVr-7XPzUg-hNraTP-87zH7W-bBhM6E-8rmXYp-48dWc8-8rbVJJ/">Arne Hoel / World Bank</a></span></figcaption></figure><p>With over 7.8 million cases of malaria, Nigeria has the highest <a href="http://www.who.int/malaria/publications/country-profiles/profile_nga_en.pdf">caseload</a> on the African continent. The disease remains one of the leading causes of avoidable death, especially in <a href="http://apps.who.int/iris/bitstream/10665/200018/1/9789241565158_eng.pdf">children and pregnant women</a>. </p>
<p>It is also responsible for about 30% of the under five-year-old deaths and a quarter of the infants that die each year. About 11% of women die from malaria during childbirth. </p>
<p>But the cost of this heavy burden is falling squarely on individuals and households who are spending a significant amount of their monthly budget on malaria-related treatment and prevention.</p>
<p>And this cost burden is exacerbated by inefficiencies in the health system. For example, even though the government gives mothers and their children free health-care services in public hospitals, problems like drug stock outs mean that women have to pay for malaria treatment out of their own pockets. </p>
<p>This means that the financial burden falls on households as money is being diverted to medical costs as well as non-medical costs such as food and transport to and from health facilities. </p>
<p>To understand the cost burden, we did a <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0078362">study</a> in two communities in Enugu State in southeast Nigeria with high malaria caseloads. We looked at the medical and non-medical costs for each episode of malaria.</p>
<p>We found that inefficiencies in the system were increasing the cost burden to individuals. And although the Nigerian government spent <a href="http://www.premiumtimesng.com/news/129141-nigeria-spends-n480bn-annually-on-malaria-control-jonathan.html">US$ 2.4 billion</a> – or 1% of its annual health budget – on malaria alone in 2013, this only covered staff salaries and the running of facilities. </p>
<p>If this money was used more efficiently, for example on interventions such as controlling the disease with insecticide-treated bed nets, the incidents of the disease could be reduced. The overall effect would be to lower the cost of prevention and treatment. This would have an impact on government’s expenditure as well as individuals’ pockets.</p>
<p>In addition, the government would have more resources to allocate to other pressing health needs such as maternal and child health.</p>
<h2>None of the costs are covered</h2>
<p>Annually 50% of Nigerians suffer from at least one episode of malaria. Children under five have an average of two to four attacks of malaria a year. As a result, malaria is responsible for about 60% of the outpatient visits to health facilities. </p>
<p>Malaria treatment is divided into in- and out-patient services. </p>
<ul>
<li><p>In-patient services: This includes the treatment of severe cases of malaria and can include consultations, laboratory tests and medication.</p></li>
<li><p>Out-patient services: This covers uncomplicated cases of malaria as well as preventive services such as providing patients with long lasting insecticide-treated nets and preventive drugs during pregnancy.</p></li>
</ul>
<p>Officially, there are a number of policies which – on paper at least – offer health care services to deal with malaria.</p>
<p>On paper pregnant women and children under five are entitled to free malaria treatment. But, in reality, not all states offer these free services. And even when they do, drug stock outs at public hospitals mean mothers have to turn to drug shops or itinerant drug sellers for medication.</p>
<p>On top of this the country has a voluntary national health insurance scheme to reduce the burden of illness borne by individuals. The scheme provides a generous benefit package (covering preventive and curative services) to employees of the federal government. But this covers only less than 5% of the Nigerian population. The informal sector, where most people work, is excluded. </p>
<p>Because the interventions are not actually working, we found that over 65% of all health expenditures in the country is borne by households through out-of-pocket spending. </p>
<p>The problem is that more than 48.4% of Nigerians live below the <a href="http://www.worldbank.org/content/dam/Worldbank/Feature%20Story/japan/pdf/event/2014/Africa-Business-Seminar-100314.pdf">poverty line</a>. Most people spend all their money on food. The high household expenditure on malaria leads to people being unable to meet other basic household needs, such as having enough food to eat. </p>
<h2>Changing the approach</h2>
<p>Reducing the malaria cost burden on Nigerians requires a multi-pronged approach. This entails addressing the high level of economic burden of malaria through concerted and sustained malaria preventive efforts.</p>
<p>But more people would also need to take up risk protection mechanisms to buffer both direct and indirect treatment costs. </p>
<p>For health system and policy research, the best practices of risk pooling and risk protection mechanisms which are suited to the developing country context need to be investigated to get an optimal uptake with people.</p><img src="https://counter.theconversation.com/content/57786/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Obinna Onwujekwe receives funding from the World Health Organization, ACT Consortium, FHI360</span></em></p>They not only bear the heaviest burden of malaria on the continent: Nigerians are also paying the most for services related to the disease.Obinna Onwujekwe, Professor of Health Economics and Policy and Pharmaco-economics/pharmaco-epidemiology in the Departments of Health Administration & Management and Pharmacology and Therapeutics, College of Medicine, University of NigeriaLicensed as Creative Commons – attribution, no derivatives.