WIt’s barely a week into 2021 and there are already urgent warnings about a new pandemic virus strain spreading secretly and exponentially around the world.
It looks like déjà vu. But in a sense, it’s a good thing: it’s not just another chapter in the exhausting saga of SARS-CoV-2, the virus that causes Covid-19, which will slowly bring newly available vaccines under control.
Mankind was not remotely prepared for our battle with SARS-Cov-2 when it appeared in late 2019.
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But be better prepared for this new enemy, called B.1.1.7, or B-117 for short.
We already understand how this new virus spreads, what public health strategies can help contain it, and how to effectively treat people infected with it. We already perform millions of diagnostic tests daily that can sensitively detect the new pathogen and distinguish it from our old enemy.
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Anyone who has already had Covid-19 is very resistant to B-117, a variant of SARS-CoV-2. In one sense, the old virus helps us against the new. Most importantly, the new vaccines developed against SARS-CoV-2, which are being rolled out in the US and several other countries around the world, are likely to protect us against B-117, which means that vaccination actions can defeat both viruses.
Yet the B-117 has two critical advantages. The one is that we are rightly exhausted to fight Covid-19. People may struggle to scrape together the energy to respond to a new viral threat, especially when the emergence of the new virus is hidden in the larger sea of SARS-CoV-2 cases. The other is that cases of B-117 could rise much faster than those of our enemy in 2020. In the UK, where B-117 seems to have evolved, most districts that imposed tiger 4 home conditions have SARS-CoV -2 cases kept flat, only to see B-117 increase every three or every week or so tenfold. . The same pattern of exponential growth apparently began in Denmark.
What could this mean for the at least 32 countries outside the UK with confirmed cases of B-117?
Assume your community uses and removes masks to maintain flat SARS-CoV-2 transmission levels, but this has detected a single case of B-117 (plus 1,000 cases of SARS-CoV-2). Over three weeks, your community may have ten B-117 cases daily (plus 1,000 SARS-CoV-2 cases). In six weeks, there may be 100 cases of the new variant (plus 1,000 SARS-CoV-2). In nine weeks, half of all cases may be B-117, and the number will continue to increase even as the spread of both viruses slows down due to infection and vaccination that builds up immunity in the population. These estimates are intended to illustrate what may happen, but are consistent with what we know about the comparative distribution of B-117 and other strains of SARS-CoV-2.
Because B-117 can grow exponentially, even in communities that keep SARS-CoV-2 under control, the situation is extremely urgent. If we want vaccination to win this new race, we must slow down the new virus while it is still rare.
Step one is to find the enemy. Thermo Fisher makes twenty million TaqPath test kits that can detect B-117 every week, showing a pattern of ‘S gene failure’ that distinguishes it from SARS-CoV-2. These kits, an equivalent of the PCR tests used to detect SARS-CoV-2 infection, and / or genetic sequencing, can be used on samples that have already tested positive for SARS-CoV-2 to see which of them is actually B-117. No emergency use authorization is required to further analyze positive samples.
Step two is to lead resources to the new and faster spreading threat. Testing and contact detection can delay the spread of rare pathogens such as B-117, but become relatively ineffective if there are too many cases. Several models (including one developed by one of us, KE) show that the detection of bidirectional sources around the sources of infection as well as those exposed to it can prevent more than twice as many cases as standard methods.
This suggests that once the first person is diagnosed with B-117 in a community, local contact detectives should abandon everything else to map the entire distribution chain of the new strain using every available resource. Veteran detectives can visit the houses of contacts to give medical advice, take samples to be mailed to laboratories to be tested for B-117 with the next day’s results, and supplies to people who need to provide self-guarantee.
Widely published guarantees of legal exemption for anything disclosed in the course of contact detection can help combat mistrust. Governments should also offer financial compensation and retention of employment to exposed individuals who are self-quarantine at home and segregated B-117 positive persons who, if necessary, in the hotel rooms or other accommodation provided by the public. Because this new threat remains rare in most parts of the world, we have a second chance to apply countermeasures to testing and detection that helped the initial spread in some places, and that hurt many others because SARS-CoV -2 has already become too much. widespread.
Step three is to consider diverting doses of Covid-19 vaccines to any region with large groups of vaccination cases throughout the community. To be clear, we have very limited data showing how well the current vaccine prevents infection or transmission of B117. The data we do have suggest that its effect may be significant, as is the case with all other viral vaccines.
Given the tremendous importance of blocking the exponential growth of B-117 early on, it’s worth trying this approach quickly, monitoring the results and adjusting as we learn how well it works. We last had this potential silver bullet. Now it can turn the tide.
Two other steps are needed. In the immediate term, diagnostics must be developed that can detect other SARS-CoV-2 variants, such as the 501. V2 strain that occurs in South Africa, but which is not yet known to travel to the USA or to many others. did not spread. countries with B-117. This variant does not yet appear as transmissible as B-117, but questions about how vulnerable it is to the Covid-19 vaccines have not yet been resolved.
We must now build a genomic monitoring system over the next few years to detect evolutionary changes in viral, bacterial and other pathogens that require new measures to protect public health, and that can detect new pandemic pathogens of any origin early enough to intervene. The need is worldwide, so as the US upgrades home systems, we need to learn from the experience of countries that were more mobile to spot new variants, such as the UK and South Africa, and help others set up their own systems. set.
Genomic monitoring will be a key pillar of the larger project to upgrade the public health information systems that have failed in many stages of the current Covid-19 pandemic.
Those who are tired and impatient of the pandemic drama ending – a category that includes both of us – can comfort them that the light at the end of the tunnel is getting brighter, although the rise of B-117 adds even more. an extra degree of urgency. Biologically, the new virus is a developed variant of SARS-CoV-2. Epidemiologically, it appears to be a clear and formidable enemy, but one for which we are much better prepared.
It’s 2021, and another race has begun. Let’s win this one.
Kevin Esvelt is an assistant professor at the Massachusetts Institute of Technology’s Media Lab, where he runs the Sculpting Evolution Group. Marc Lipsitch is a Professor in the Departments of Epidemiology and Immunology and Infectious Diseases at the Harvard TH Chan School of Public Health, where he also manages the Center for Communicable Disease Dynamics.