Study: Individuals Recovered From COVID-19 Are Protected for Up to 6 Months

Most individuals with mild COVID-19 produced antibodies that protect the individual from reinfection for up to 6 months, the results of a study from Michigan Medicine at the University of Michigan showed.

“Previously, there was a lot of concern that only those with severe COVID-19 produced strong antibody responses to infection,” Charles Schuler, MD, clinical assistant professor of allergy and immunology at Michigan Medicine, said in a statement. “We’re showing that people with mild bouts of COVID-19 did really well after their infection, made antibodies, and kept them.”

The results showed that about 90% of individuals in the study produced spike and nucleocapsid antibody responses.

All but 1 had persistent antibody levels at the time of the follow-up, the study results showed.

None of the individuals who produced antibodies were reinfected, and their antibodies’ ability to neutralize COVID-19 did not differ significantly from the first visit, 3 months after the initial infection, and the last follow-up, 6 months after the initial infection.

The study enrolled 130 individuals, all of whom had a confirmed COVID-19 illness between 3 and 6 months after their initial infection. Three of those individuals were hospitalized, but the rest had mild symptoms, such as chills, headaches, and loss of smell or taste, and were treated as outpatients.

The individuals were either health care workers at Michigan Medicine or individuals with a high risk of exposure to COVID-19, and most also took part in a previous study by the same research team.

The investigators are working on analyzing samples of the same subject group to evaluate the antibody response further. They also found that individuals with COVID-19 can delay vaccination for 90 days after the infection ends.

“These results are encouraging for those who have already run the gauntlet of COVID-19 infection,” Schuler said.

“However, I do not recommend citing this study as a reason not to be vaccinated for those never previously infected. Vaccination decreases infectiousness, the risk of hospitalization and deaths from COVID-19, without having the actual infection,” Schuler said.

“Achieving natural immunity by deferring vaccination in favor of infection is not worth going through the discomfort, risk to yourself and risk to others,” he said.

Reference

COVID-19 antibodies persist, reduce reinfection for up to six months, study finds. EurekAlert. News release. September 14, 2021. Accessed September 15, 2021. https://www.eurekalert.org/news-releases/928365