Can I get COVID again if I’ve already had it?
Is it possible to be reinfected with COVID-19 if a person has already had it and recovered? New research says the answer is yes, but so far it seems to be rare. Very few people worldwide have had confirmed cases of reinfection. So, many people think it’s an uncommon occurrence.
How can we tell the difference between two infections and one long infection?
Doctors can confirm reinfection when they sequence the genome of the virus from both the first and second round of symptoms. As the virus gets passed from person to person, it mutates a small amount. Over time, there can be enough mutations that two viruses can be distinguished from one another. If the genetic difference between the two samples is greater than we expect with one long infection, then we can say it is a new infection.
How can people get sick a second time? Aren’t they immune?
Second infections may be due to both virus mutations and waning immunity after just one exposure. A second infection with COVID-19 can result in a stronger immune response than the first. It is safe to say we need more data to say for certain how often reinfection happens. Continued surveillance and research is the only way to figure it out. And the more we know the more effective our vaccines and treatments will become.
Last update: October 20, 2020, 9:00 pm ET
Science review: ERS, JAB