Matt Hancock’s Covid cavalry is not yet on the horizon. We need a global approach now
As the UK battles with the overwhelming demand for Covid-19 tests, the health secretary, Matt Hancock, said on Friday that the country needs to come together to keep the infection levels down while we await the cavalry on the horizon.
The cavalry, he said, would come in the shape of the science that will bring a vaccine, effective treatments and the ability to undertake mass testing. Detecting cases, tracking contacts and containing the spread of infection remains our strongest weapon.
But the truth is we need urgently to find new approaches to achieve mass testing because the cavalry might not be here soon; we are in this for the long haul. This is now a global endemic infection – which means it is present within communities all the time, across the world.
It might help to underline some essential points: Covid-19 is a serious disease that is lethal to some, causes devastating illness in others and yet can be completely symptom free in about 70% of cases. The risk varies enormously.
As we return to work and school,
the surge in demand for testing is not a surprise, but neither is the difficulty that the system is having in keeping up. This scale of demand amounts to mass testing, but we do not yet have the systems or technology for the role we need mass testing to play – especially in the absence of a vaccine and effective antiviral drugs.
Remember that testing for Covid-19, or any infectious disease, is undertaken for different purposes: diagnostics, case detection and screening, and also surveillance. Diagnostic testing is where patients with symptoms are tested for the presence of an infection for the purpose of managing and treating an individual. Screening, however, is undertaken typically in people without symptoms to find out whether anyone within a group of people, such as in a workplace, school or care home, is infected and so a risk to others. Finally, there is surveillance. Here the sample identification is often “de-linked” from the person giving the sample and so the results are anonymous – this epidemiology testing tells us how much virus is present in a given community, region or country.
Diagnostic testing needs to be very reliable, because care and outcomes depend on it. Screening also requires accuracy, because it might be guiding whether people are safe to return into a larger group – such as a nurse returning to work. Surveillance can be less accurate because the findings are not used for guiding treatment or possible exposure to infection, but in understanding how much virus is circulating in a population and how high the infection rate is.
The UK has done well at building capacity and is achieving high numbers – although just consider how hard this would be to put in place in a lowincome country with highly dispersed populations. But to achieve the level of case detection needed we must develop better technology, and solutions that will work here and around the world.
This is the mass testing solution that Hancock referred to as being on the horizon. The terms “rapid test” and “point of care” are often used, and we have both antigen and antibody testing. The dream scenario would be a handheld device that could be used with minimal training to measure whether virus was present (antigen testing) and if there were antibodies indicating past infection.
The new rapid test kits announced last week for use in the UK perform a polymerase chain reaction (PCR) test in a desktop machine, rather than needing a full lab – useful for testing new suspected cases at hospital admissions. Others in development measure viral protein and can be made much smaller, and bring the potential of cheaper tests undertaken in the community. However, this technology is currently less accurate.
Here is where we can learn from our experiences with diseases such as HIV and TB, where rapid tests are commonly employed using inexpensive antibody kits – with findings confirmed using a laboratory PCR test. Antibody tests use blood samples and detect whether someone has had a past infection. These tests work some weeks after infection and could be useful for testing if someone could return to work, but we are still learning about how long immunity from a prior Covid-19 infection lasts.
Many countries are struggling because they have had to repurpose their HIV, malaria and TB laboratories for Covid testing, while trying to avoid disrupting the systems in place for those diseases. Here, engaging with the community to keep ongoing programmes for other diseases running has been vital.
This is another key lesson from these global diseases: the importance of building public trust and good public health messaging. I work with colleagues in countries such as Peru, Brazil, Bangladesh and Zimbabwe who are running studies to understand the nature of the disease and its impact in their very different situations, but with challenges that are not dissimilar.
I spend hours in meetings with these incredible teams and then step back from my screen into what we are living here. We have much to learn from each other and I know from our experiences with other diseases that we will get there faster if we work together, stop looking for nationalist solutions, and work globally to tackle this – and future – pandemics.
We are waiting for a vaccine and, to this end, global cooperation is encouraging, with research teams sharing data and initiatives such as Covax, working to ensure global equity in access to vaccines. There are also many rapid tests being developed for Covid-19 across the world and this effort is crucial if we are to achieve the scale of global mass testing needed.
We need validated, proven and accessible final products, and surely this would be more likely if coordination and collaboration were put in place now. For this, we need a strong, neutral, global agency supported by all nations, to build partnerships, agree standards, facilitate sharing and streamline these developing efforts. Is that the World Health Organization? Let’s hope so.
• Professor Trudie Lang is director of the Global Health Network, Nuffield Department of Medicine, Oxford University
We will get there faster if we work together and stop looking for nationalist solutions to pandemics