Slow Spread? Acceleration Could Be Safer

To mitigate that risk, policymakers must accept the rapid spread of milder variants. This will require tough trade-offs but will save lives in the long run. We should end cover-ups and social distancing in most settings not because they don’t slow the spread — the usual argument against such measures — but because they can can do.

To understand why, let’s first consider an important scientific difference, between antigens drifted and antigens change. Antigens are molecules — such as a mutant protein of SARS-CoV-2 — that the immune system detects as foreign. Then, the host’s immune system mounts a response.

“Antigen drift” describes the process by which single point mutations (small genetic errors) occur randomly during viral replication. The result are small changes to antigens such as mutant proteins. If a point mutation makes the virus less likely to survive, that variant will eventually die out. But if the mutation confers an increasing survival advantage – such as the ability to spread more quickly from cell to cell – then that strain of bacteria will be more likely to spread in the population.

Antigenic drift is a gradual process of change: A single point mutation changes a peptide, or building block, of a larger protein. Hosts that have acquired immunity against a prior strain usually enjoy at least partial immunity against “drift” variants. This is called “cross protection”.

Every time an immune host is exposed to a slightly different antigenic variant, the host can tailor its immune response without becoming seriously ill. And the more similar the new strain is to the last version the person fought, the less risk that strain is to the host.

In contrast, “antigen shift” refers to a discontinuous quantum jump from one antigen (or set of antigens) to a very different antigen (or set of antigens). New strains of viruses – such as those that jump from one species to another – tend to emerge from antigenic shifts. The biological causes of antigenic shift are often different from those that cause antigenic drift. For example, physical swapping of entire sections of the genome results in more significant changes to viral genes than changes caused by individual point mutations.

But there is a very disturbing paradox: How many single point mutations constitute an antigenic shift, especially when human hosts are deprived of the opportunity to update their immune response to with “drift” variants?

People who are immunized and naturally immunized can improve their immune response to new virus strains created by antigenic drift. However, social distancing and concealment increase the risk of emergence of vaccine-resistant strains from antigens change by minimizing the opportunity for immunized and innate immune systems to modulate their immune responses through periodic exposure to incremental “drift” variations.

This is a familiar concept in virology. The increase in severe cases of shingles over the past decade is partly a result of the widespread use of the chickenpox vaccine. Shingles and chickenpox are both caused by the same virus. Before the widespread use of chickenpox vaccine, parents regularly updated their own immunity by being exposed to chickenpox from their children, or from other adults exposed by children. . However, now that most children are vaccinated against chickenpox and do not get it, older adults get more severe cases of shingles.

The absolute risk of a more virulent strain of SARS-CoV-2 is low. That’s because viruses are “more interested” in propagating themselves than killing their hosts: Most viruses evolve to become more infectious and less virulent. But this is just a rule of thumb, not a law of biology. Like any trend, we should expect a distribution of results around the method — and the more iterations you allow, the more likely you are to get an unexpected result. The implementation of social distancing policies in the context of widespread vaccination makes the possibility of the emergence of vaccine-resistant superbugs more likely.

Why not prepare for this outcome simply by developing new vaccines against new strains more quickly? Because even mRNA vaccines cannot be developed fast enough to overcome the vaccine resistance monitor. On December 8,

Pfizer

committed to deliver the first batch of new vaccines including the Omicron variant within 100 days. However, by mid-March, a significant percentage of the US population was infected with Omicron.

Meanwhile, mask regulations and social distancing measures will create fertile ground for new variants to more effectively evade vaccination. Substantial changes in antigens can create new strains that are increasingly difficult to target with vaccines. There is no vaccine for many viruses, despite decades of efforts to develop them.

Will easing restrictions come at the cost of more hospitalizations and deaths as the next variant begins to spread? Perhaps, but it will reduce the risk of worst-case scenario and greater loss of life in the long run.

The most important step in fighting the Covid-19 pandemic is the distribution of a vaccine. With this milestone now reached, the global response should shift from preventing spread to minimizing the probability of antigenic change. Whether SARS-CoV-2 was made in a lab is still up for debate, but let’s make sure we don’t create an even more deadly strain with the wrong policies.

Mr. Ramaswamy is the founder and executive chairman of Roivant Sciences and the author of “Woke Inc.: Inside Corporate American Social Justice Scam.” Dr. Ramaswamy is an assistant professor of otolaryngology at Ohio State University Medical Center.