A COVID-Vaccinated Summer Could Be Wonderful - The Atlantic

A COVID-Vaccinated Summer Could Be Wonderful - The Atlantic Variant strains that increase the transmissibility of the virus could also throw these estimates off, Shaman noted. As the virus mutates, the reliability of immunity from prior infections also changes. The recent outbreak in Manaus, Brazil, suggested that even high levels of past infection didn’t necessarily protect a population for long. Fundamentally, we still do not know how herd immunity will work—if it even does. “The most important thing to remind ourselves of is that herd immunity is only relevant to consider if we have a vaccine that blocks transmission,” says Shweta Bansal, a biologist at Georgetown University. If it turns out that vaccinated people can still carry and spread the virus, then a group cannot assume that they are protected because people around them are vaccinated. It would mean that the finish line is not 70 percent, but 100.