Vaccination is not enough

February 03, 2021 09:23
Photo: Reuters

In the next stage of the fight against COVID-19, can we rely on vaccines alone? Although vaccination in the United States and some other countries is beginning to pick up pace, in most countries it hasn’t even begun. Meanwhile, new variants of the coronavirus that are impacting other parts of the world have also appeared in the US – and there are indications that existing vaccines may be less effective against some of them.

Fortunately, we can take advantage of another encouraging development that has received relatively less attention. In places that have established regular COVID-19 screening tests – at universities, schools, and other places where everyone is tested at least once per week – data from the past six months indicate that infection rates can be kept down to less than 0.5% (one positive person per every 200 people tested each week).

This is significant, because many of these programs operate in places where, according to the official statistics, the reported positivity rate in the surrounding community is much higher – up to 10% in some cases (ten positive people per every 100 tested each week). This is true, for example, of public schools in Watertown, Massachusetts and New York City. Even in places where the infection is surging, transmission can be limited in environments such as schools. If this low infection rate is truly possible in general, and if the operational procedures that make regular testing possible are scalable, we can operate schools, childcare, and many workplaces in a much safer manner – during and even after rollout of the vaccine.

The reason for these relatively low infection rates in places where people live and work in close quarters is straightforward. Mitigation measures – including wearing good masks, maintaining safe distancing practices, and ensuring adequate ventilation – are effective. And regular testing breaks the chain of infection by identifying people who need to be isolated. Testing also helps everyone – teachers, parents, students, staff, and administrators – see that the mitigation measures are working, encouraging compliance and helping to identify weaknesses or breaks in defenses.

Being able to contain infection rates even in school settings is a remarkable achievement, but can it be scaled?

Fortunately, Congress has provided a great deal more funding to support school reopening. Massachusetts recently announced a scheme that will apply lessons learned by leading labs, test providers, and schools, and, to help with reopening, financial support will be offered to any school system that would like to implement weekly pooled testing as part of a broader mitigation program. Every state can now invent its own version or, we would suggest, combine lessons from what works in other parts of the country. Our public service website, www.covidresponseadvisors.org, attempts to support such innovation.

The Massachusetts plan relies on pooled testing, whereby samples of up to 25 people (depending on the lab) are first tested together. If there are any positives, follow-up tests are run to “deconvolute” those pools (figure out exactly who is infected). The demonstrated low rates of COVID-19 in schools make this method efficient. While it might not make sense to pool samples from a community testing site where the test positivity is upwards of 10%, in a school with a rate of under 0.5%, pooled testing is incredibly efficient. This is a viable and robust approach, although there is also hope that more sensitive rapid tests will become more widely available in this context.

The main issue now is to ensure that everyone who wants to participate in such programs can do so. Testing is a proven solution: it has been able to keep professional sports teams playing and schools open even in high-prevalence areas. Established testing protocols should be made available to more schools and to childcare workers – who have continued working in person throughout the pandemic, despite a lack of access to resources – as we wait for vaccines to effect change in all communities. As the new and more contagious variants take hold in the US, being able to track and contain cases in schools will be even more essential to reopening strategies.

Eventually, we will prevail against COVID-19. One hopes we can do so sooner and at lower human cost. But we also need to ensure that we don’t leave anyone behind in our efforts to bring everyone to a healthier and safer future.

That means wiping out the virus everywhere and among all populations. Eradication will be a long haul. Combining vaccination, testing, and other mitigation measures is essential to getting there.

The article is co-authored by Anette (Peko) Hosoi ,Associate Dean of the MIT School of Engineering and Melea Atkins, a health and economic policy consultant.

Copyright: Project Syndicate
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Simon Johnson, a former chief economist of the IMF, is a professor at MIT Sloan, a senior fellow at the Peterson Institute for International Economics, and co-founder of a leading economics blog, The Baseline Scenario. He is the co-author, with Jonathan G