TO relax Covid-19 restrictions when large numbers of individuals remain unvaccinated is inherently risky, biologists have warned.
They argue that it will promote the evolution of new strains that are more transmissible and more likely to evade the protection from current vaccines.
Removing restrictions when children and other vulnerable groups are unvaccinated may inadvertently give rise to more infectious and possibly more dangerous variants.
The authors of the new article recommend that measures such as the mandatory wearing of face masks remain in place until most of the adult population is vaccinated. They add that the benefits of vaccinating children may now outweigh the risks.
We are in an evolutionary “arms race” with SARS-CoV-2, which is the virus that causes Covid-19, biologists at the University of East Anglia in the United Kingdom have warned.
Writing in the journal Virulence, they say that relaxing control measures while the majority of the world’s population remains unvaccinated risks the evolution of more transmissible, more virulent variants.
These variants may be more dangerous for children and certain vulnerable groups, such as transplant patients with compromised immune systems, they argue. They may also escape the protection afforded by existing vaccines.
Even in countries where vaccination has reduced the numbers of hospitalizations and deaths, high case numbers and large numbers of unvaccinated individuals provide a mixing vessel in which new variants can emerge.
“Relaxing restrictions boosts transmission and allows the virus population to expand, which enhances its adaptive evolutionary potential and increases the risk of vaccine resistant strains emerging by a process known as antigenic drift,” they write.
Antigenic driftTrusted Source refers to the continual random mutations in a virus’s genome that change the proteins on the virus particle’s surface.
Stay informed with live updates on the current Covid-19 outbreak and visit our coronavirus hub for more advice on prevention and treatment.
These are the foreign proteins, or “antigens,” that antibodies recognize. For SARS-CoV-2, the most important is the spike protein that allows the virus to invade cells.
Every change in this protein has the potential to interfere with the immune system’s ability to recognize and disrupt the virus, which will reduce the protection provided by a past infection or vaccination.