An Icelandic study published in the New England Journal of Medicine has found that COVID-19 antibodies last at least four months without declining. The research suggests there is little likelihood of developing COVID-19 twice. It also suggests vaccines could be effective in preventing infection over a long period, even with just one or two doses.
The study measured antibodies in samples from 30,576 people, including 1,237 who had recovered from SARS-CoV-2 infection. Among those who had recovered, antibodies proved higher in older people and those who were hospitalised. Men tended to develop more antibodies than women, and there was a positive correlation between the severity of illness and the amount of antibodies. Those who showed only slight symptoms or were asymptomatic general developed fewer antibodies to SARS-CoV-2.
One- or Two-Dose Vaccine
Kári Stefánsson, CEO of DeCODE genetics, which conducted the study, told RÚV that in light of the study results, a vaccine could provide relatively long-term protection from infection. “This indicates that antibodies formed during vaccination should be able to last considerably,” Kári stated. “You do not need to be vaccinated more than once or maybe twice, but in any case, it seems to last considerably.”
Reports of Reinfection Not the Norm
Kári stated that rare reports of cases abroad where individuals are believed to have been infected more than once should not cause alarm for the average person. “When 25 million people have been infected with this virus, it must have reached people who are diverse when it comes to the immune system. But that doesn’t mean that ordinary people who have been infected are at high risk of reinfection.”