The coronavirus contact tracing app for England will not be rolled out until winter, the minister responsible for overseeing it has said. Meanwhile, the NHS Test and Trace system, in which individual contact tracers follow up with people who have been in close proximity to positive cases of COVID-19, has been plagued by difficulties.
The New York Times has reported that despite the UK having had nearly 300,000 cases of the disease and more than 40,000 deaths, some contact tracers have not yet spoken to a single person.
But when the coronavirus pandemic broke out, there was already a group of people who were very well prepared to help the government’s tracking efforts – the NHS workers who carry out contact tracing in cases of sexually transmitted infections.
In the world of sexually transmitted infections, contact tracing is known as partner notification. The task of health advisers, employed in sexual health clinics since the 1950s, is to support people who have been diagnosed with sexually transmitted infections to get their sexual contacts tested and treated as well.
They work with other highly trained professionals who are also used to having difficult conversations with people who have been exposed to infection, in the health protection teams of Public Health England and local government Environmental Health Departments.
Contact tracing for sexual health
So what happens in sexual contact tracing, and what are the lessons for coronavirus?
First, a contact tracer builds a risk assessment of the “index patient” – the person who has just been diagnosed with a sexually transmitted infection, say gonorrhoea or syphilis, and may be very distressed. They may not even believe the test result.
This discussion, in person or by phone, involves sharing highly personal information. It requires trust – in the person, in their competence and in the institution that will be holding their information. The contact tracer explores with the patient who else has been exposed to the infection. How they can be contacted. Do they already know of the diagnosis? How likely is it that transmission took place? Did they use a condom (and if so, was it used correctly)?
Some “high value” patients will have many contacts needing to be tested and treated and may also need other forms of care. Someone with many sexual partners may need a hepatitis B vaccination and pre-exposure prophylaxis to stop them contracting HIV.
At the end of the consultation, there needs to be a clear plan for what will happen next and when, and clarity on what support will be offered. Very importantly there needs to be an open door to return quickly and disclose something too sensitive for a first conversation. Speed is of the essence.
Clinics routinely take part in local and national audits of their effectiveness, and wide-ranging research confirms the importance of contact tracing in the control of sexually transmitted infections.
Lessons for coronavirus
Coronavirus contact tracing aims to prevent onward transmission by isolating people. It also seeks to alert people who have been exposed to an infection so they can get tested and reduce their risk of illness or complications.
However, unlike in cases of sexually transmitted infections, self-protection through treatment isn’t possible after exposure to coronavirus, making contact tracing more challenging. The person contacted may have little to gain from the warning and they may be seriously disadvantaged by an instruction to self-isolate.
In this case, the value of a case in reducing the R number will need to be assessed terms of who they are at risk of exposing. Are they in a large and crowded household? Are they in a job where social distancing is difficult? Are housemates particularly vulnerable to severe illness? What are they afraid of and how can they be supported?
Contact tracing must support the individual in making the best decisions, and for some the news they have been exposed will be very distressing. They may fear for the life of a household member or vulnerable contacts and have financial worries. As a result of a phone call, a whole household may need support with a range of financial, physical and mental health issues.
And how do we measure its effectiveness? This remains a challenge even for sexual contact tracing, which has been taking place for decades.
A missed opportunity
So what kind of infrastructure is needed for coronavirus contact tracing to be a success? The UK’s network of sexual health clinics is unique as a locally embedded public health infrastructure with experience in contact tracing operations. Together with Environmental Health and Health Protection Departments, these should have been an ideal basis for a new system to track coronavirus.
Their mutual links and networks cross the NHS, including GPs, hospitals and laboratories, which give their staff a trusted place from which to start difficult conversations and collect sensitive information. Also, importantly, they are linked to other health services.
Building on its existing infrastructure, Germany used previously underfunded local health offices in its much-praised coronavirus response, ramping up the contact tracing function of its Gesundheitsämters - local government authorities similar to our Environment Health and Health Protection units.
England has to date taken a different route, choosing instead to develop a new, national, dedicated contact tracing system run by the private provider SERCO, which accidentally leaked the email addresses of 300 contact tracers in May.
Most of the recruited coronavirus contact tracers are entirely new to the role and lack the support of professionals experienced in these tricky issues. They also lack the networks into GPs and other local NHS services that can support households in a time of stigma, strain and fear.
It’s a shame that this existing workforce of experienced contact tracers was overlooked in the government’s coronavirus strategy when all the UK and international evidence points to the benefits of integrating contact tracing with existing public health structures. But the fight against COVID-19 is a marathon, not a sprint - there’s still time to build coronavirus contact tracing into the DNA of NHS and public health services.