Heatwaves are returning to southern parts of Australia. Temperatures in Hobart reached 38.7C on Monday, Adelaide has another run of 40C-plus days looming, and Melbourne is facing a weekend high of 41C.
Meanwhile, the death toll mounts. The number of people who died during Melbourne’s heatwave earlier this month was more than double the weekly average of 98 for that time of year.
This summer, Melbourne is already facing 13 days over 35C. And we can expect hotter summers in years to come. Melbourne may face up to 26 days over 35C a year by 2070; Adelaide could see up to 47 days of extreme heat and Perth, up to 76 days.
One estimate is that the number of heatwave-related deaths in Australia’s capital cities will quadruple by 2050. But accurately estimating the future health impact of heatwaves is challenging because of the uncertainties related to future temperature projections and population susceptibility to heatwaves.
Heat exposure, in its most simple form, emanates from the sun and the warming climate. Mitigation of climate change is the obvious solution, but that is not happening quickly enough to protect more Australians from dying during heatwaves.
Heat represents a classic public health issue requiring committed government action to prevent deaths, and to steer Australia through the difficult adaption process. A comprehensive heat policy must incorporate education, training, resilience boosting, effective health management systems, and broad integration with other sectors, such as urban planning, housing design standards and transport policies.
Education and prevention
All Australians should be equipped with the knowledge to recognise the early signs of heat stress and be ready to supply first aid to those who succumb to the heat. First aid courses are already relatively inexpensive, but a government subsidy would encourage greater uptake.
In addition, education campaigns can alert people to the early symptoms associated with dehydration – profuse sweating, high body temperature, lethargy and listlessness, lack of appetite, thirst and irritability – that require monitoring. The person may just need to rest in a cool place and replenish their fluids, or there may be more serious signs that require medical attention.
Exercising, working, or even walking at a fast pace becomes difficult to sustain at temperatures above 35C. When a fever raises our core temperature above 38C, we start to feel unwell and death is likely if core temperature passes 40C. So preventive health programs must extends to the workplace, sporting arena and throughout the community.
Personal protection requires an accurate understanding of the individual risks, coupled with a selection of readily accessible, effective options to minimise heat exposure. Governments have a role in educating communities and high-risk groups about how to minimise their heat exposure, facilitating cooling centres, transport, and providing strategies to ensure all high-risk people are offered protection.
However, strategies need to be relevant to the local community and intersect with other services. It would be wasteful to scurry an elderly woman away to a cooling centre, for example, only to have her neighbours call on the police to retrieve her.
Other adaptive components include building resilience among the community. For protection against heat, this involves acclimatisation, hydration, awareness of protective behaviours, and the elimination of factors that heighten risks. A range of common medications, for instance, can interrupt physiological responses to heat, so prescribing doctors need to discuss these risks with their patients.
Early warning systems
In response to the 2009 Victorian heatwaves, when there were 374 “extra” deaths beyond what would usually be expected, the state government initiated a Heat Health Alert System to operate from December 2013 to the end of February 2014.
The alerts were not designed to inform the public directly. Instead, alerts are emailed days in advance to government authorities and agencies, health, aged and emergency services, and advocacy groups. Recipients are then expected to monitor local conditions, and respond in accordance with their own pre-determined heatwave plans. This appears to be little more than a duplication of the warnings already issued by the Bureau of Meteorology, with an additional trigger threshold.
It is perhaps unfair to evaluate a system that has been operational for only one month. But we can’t ignore the 100 extra deaths, some of which may have been prevented by a better public information and heatwave planning.
The South Australian Health Department, which works closely with a heat research team, has made some inroads. A government website provides a suite of public information, in multiple languages, to educate, inform and train South Australians to better manage their own heat exposure risks.
But although it’s an excellent start, a more comprehensive approach is needed; prevention requires more than risk awareness and heat management tips.
Health systems response
Heatwaves tend not to sneak up on us. The Bureau of Meteorology provides adequate detailed and accurate warnings of the likely heat events, several days in advance. This is adequate time for health planners to staff ambulance teams and emergency departments. Hospitals and ambulance services require flexible models of resource allocation to deliver the surge capacity.
Heat stress is an emerging hazard and now affects thousands every year. Yet historically, it has not held high priority on the health agenda, hence much of the existing health workforce trained with minimal or no education in the management of heat stress. Management of heat stress now needs to be included in health curricula, and modules made available for existing health workforce.
Coordination across sectors
Health protection is not limited to activities of health departments and health workers. Urban landscape design, housing standards, transport strategies, and occupational health and safety policies significantly influence heat exposure pathways. Streets and public transport waiting stations that offer no shade, for example, will become increasingly hazardous to health.
Human health ought therefore be considered in policy development in these external domains. But coordination of effort across portfolios will not occur without a designated and broadly endorsed process to drive it.
A Heat Commission, receiving bi-partisan support, appropriate funding, with the authority to influence policy across sectors, would have the capacity to collate the evidence, work with policy makers and stakeholders, and lead Australia into our hotter future.
Australians are already living with intolerably high temperatures. A significant investment in public health, research into adapting to the heat, and coordinated planning is urgently required to address this new health burden.