Science

COVID: researchers warn about the potential risk of immune escape of future variants

As the number of people vaccinated continues to increase across the world, the variants are still worrying scientists. Several British scientific institutions have called for the development of plans for the management of variants, with public health measures if necessary, such as a return to mass lockdowns. According to the researchers, in fact, it is not impossible that vaccine-resistant variants could emerge.

Recent articles produced by the Scientific Advisory Group for Government Emergencies (SAGE) have suggested that the arrival of a variant that eludes vaccines is a “realistic possibility.” The group supported further work on new vaccines that reduce infection and transmission more effectively than current vaccines, the establishment of more vaccine production facilities in the UK, and laboratory studies to predict the evolution of variants.

The risk of immune escape posed by the new variants

With the arrival of a new variant considered to be one of the main dangers likely to further intensify the crisis, leading scientists have highlighted the risks. Professor Graham Medley, a member of SAGE and head of the government’s COVID modeling group, said it was ” clearly something that planners and scientists should take very seriously, as it would set us back far “.

It’s not that different from the planning that needs to be done between pandemics – a new variant that can significantly overcome immunity would essentially be a new virus. The advantage would be that we know we can generate vaccines against this virus – and relatively quickly. The downside is that we would be back to the same situation we were in a year ago, depending on the impact of the current immunity against a new variant. Hopefully the evolution is slow, so that the new variants that appear are only slightly evasive. “.

Structure of the S protein (Spike) of SARS-CoV-2 in its closed configuration, in its original form D614 (left) and its mutant form (G614). In the mutant spike protein, loop 630 (in red) stabilizes the protein, preventing it from opening prematurely and making the virus more infectious. G614 is the common ancestor of variants and the first variant of interest to have been detected. In the future, the appearance of variants escaping vaccines may be possible. © Bing Chen, PhD, Boston Children’s Hospital

Marc Baguelin, of the Imperial College COVID response team and a member of the government’s SPI-M modeling group, explains that it would be essential to prevent the importation of variants of concern with ” moderate to high immune escape properties, as they could lead to future waves several orders of magnitude larger than those encountered so far “.

Such a new virus is unlikely to escape immunity entirely from infection or previous vaccines. Some immunity should persist at least for the most serious outcomes such as death or hospitalization. We would most likely be able to update current vaccines to include the emerging strain. But that would take months and mean we may have to reimpose restrictions if there was a significant risk to public health. The extent of the restrictions would be a political decision and should be proportionate to the extent to which this virus eludes current vaccines “.

Managing the virus in England

This is accompanied by a further easing of restrictions in England on Monday when fully vaccinated people and those under the age of 18 will no longer be legally required to self-isolate if they come in close contact with someone with COVID. They will be advised, but not required, to take a PCR test instead.

Meanwhile, all 16 and 17 year olds in England will be offered a first dose of the vaccine over the next week to give them some protection before schools return in September. Health Secretary Sajid Javid urged older teens not to delay. ” Get your doses as soon as you can so that we can continue to live safely with this virus and enjoy our freedoms by providing you, your family and your community with the protection you need. “.

Former Boris Johnson senior adviser Dominic Cummings has previously called on the government to release a variant escape vaccine contingency plan and suggested MPs should explore ways to force ministers to do so . A scientist, speaking on condition of anonymity, said he would like to see the publication of the national risk assessment for COVID emergency plans.

Government sources said the Public Health England and others were controlling the situation with rapid surveillance and genomic sequencing of the virus. A spokesperson for the Ministry of Health and Social Affairs said the immunization program had built a “wall of defense”. ” We are committed to protecting the progress of vaccine deployment and our advanced genomics capabilities are at the forefront of global efforts to stay ahead of variants, with over half a million samples sequenced to date. “.

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