The pandemic has returned with a fury. COVID-19 cases are once again rising as the delta variant wreaks havoc on communities around the country.
Hospitals are once again facing a surge of patients and deaths, and nearly all people facing serious or life-threatening symptoms are unvaccinated. But there have been breakthrough cases of vaccinated people becoming infected. While the disease may be less serious for them, each newly-infected person is a chance for the virus to mutate and create newer and possibly more serious mutations.
"The more chances we give it to make these random changes, the greater the likelihood that it’ll hit upon some combination that makes it more transmissible and/or less recognizable to our immune systems than even the delta variant is today," says Thomas Friedrich, a virologist and professor of pathobiological sciences at UW-Madison's School of Veterinary Medicine who has a doctorate.
The delta variant is more contagious than the initial variants of COVID-19, and it's able to overcome some of the immune system's protections developed by the vaccine, he says. And while vaccinated people experience less serious symptoms, initial studies have found they may be just as contagious as unvaccinated people.
Despite some common misconceptions, Friedrich says that even people who've been infected with COVID-19 need to get the vaccine. "The level of immunity that [people who've had COVID-19] get when they're done with their infection can be quite variable. Some people can have very strong and long-lasting immunity, others will have much more modest levels of an immune response," he explains.
Friedrich adds that these immunes responses tend to lessen over time, and the vaccine provides a more reliable form of immunity.
