TUESDAY, Nov. 17, 2020 (HealthDay News) -- Immunity to the new coronavirus may last six months or longer after people recover from infection, a new study suggests.
Researchers collected blood samples from 149 patients who had COVID-19 early in the pandemic and analyzed them for immune cells that make antibodies that block the SARS-CoV-2 virus from entering cells.
One month after infection, all of the patients had coronavirus-fighting antibodies. Six months after infection, those antibodies were more potent and better at fighting mutated versions of the virus.
The work, which was posted online Nov. 5 as a preprint to bioRxiv.org, hasn't undergone peer review. Research is typically considered preliminary until it has been peer-reviewed.
The findings suggest that the immune systems of people who've been previously infected might be ready to combat the virus if they're exposed again, according to the team at Howard Hughes Medical Institute in Chevy Chase, Md.
"The really good news is that people who are infected are very unlikely to become sick again for at least six months," said study author Dr. Michel Nussenzweig, an immunologist at The Rockefeller University in New York City.
Dr. Christian Gaebler, an immunologist in Nussenzweig's lab, pointed to other positive news from the study.
"Our results showed that it's not hard for our immune systems to make effective antibodies to SARS-CoV-2," Gaebler said in an institute news release.
While antibody levels were generally low, their presence in so many recovered patients is a positive sign for vaccine development, the researchers said.
"Our idea was that if we're able to find such neutralizing antibodies, we would know what part of the virus vaccines have to target," Nussenzweig said.
The antibodies might also provide a blueprint for developing drugs to prevent or treat COVID-19, according to the researchers.
The study provides important insight into how durable people's immune responses are, said Leo Stamatatos, an immunologist at Fred Hutchinson Cancer Research Center in Seattle who reviewed the findings.
"This work suggests that our bodies can remember SARS-CoV-2 for at least half a year -- and probably longer," he said in the news release. "That's a good thing."
For more on COVID-19, go to the U.S. Centers for Disease Control and Prevention.
SOURCE: Howard Hughes Medical Institute, news release, Nov. 11, 2020