Herd Immunity To COVID-19 May Be Closer Than We Think, New Studies Say
Herd immunity. You’ve heard the term — and you’re about to hear it a lot more.
Under herd immunity, a virus begins to wane — with spread dramatically reduced — because so many people have already had it and thus built up immunity.
And several new studies show that we may be moving toward herd immunity more quickly than previous research suggests. While some of the studies use small sample sizes and the findings are not definitive — and while Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, warns that even an effective coronavirus vaccine may not be enough to achieve herd immunity — the studies are at least promising.
“The prevalence of immunity to the coronavirus that causes COVID-19 may be much higher than previous research suggests according to an intriguing new study by researchers associated with Karolinska Institute in Sweden,” Reason magazine reported. “In addition, a new German study by researchers associated with the University Hospital Tübingen in Germany reports that people who have been previously infected with versions of the coronavirus that cause the common cold also have some immunity to the COVID-19 virus. If these reports stand up to further scrutiny, it would be very good news because they suggest that the pandemic could be over sooner and ultimately be less lethal than feared.”
In the Swedish study, researchers not only checked 200 participants for the presence of immunological proteins called antibodies produced in response to COVID-19 infections, but also for T-cells which are another virus-fighting component of the immune system. Detecting and evaluating T-cells is a bit trickier than measuring antibodies.
The Karolinska researchers, according to the accompanying press release, “performed immunological analyses of samples from over 200 people, many of whom had mild or no symptoms of COVID-19.” The study tested COVID-19 patients, exposed asymptomatic family members, healthy blood donors who gave blood during 2020, and a 2019 donor control group.
“One interesting observation was that it wasn’t just individuals with verified COVID-19 who showed T-cell immunity but also many of their exposed asymptomatic family members,” Soo Aleman said in the release. “Moreover, roughly 30 per cent of the blood donors who’d given blood in May 2020 had COVID-19-specific T cells, a figure that’s much higher than previous antibody tests have shown.”
And another new model from Nottingham and Stockholm Universities suggests that such immunity might be closer than many in the mainstream media say. “According to their new mathematical model, far less people need to be infected with COVID-19 in order to reach herd immunity levels,” StudyFinds.com reported.
“That model, which was specially designed just for this study, categorizes people into different groups based on age and social activity levels. Once those factors are incorporated into herd immunity projections, the percentage of a population that would have to become immune drops from 60% to 43%,” they said.