Natural immunity to COVID-19 may not last long

Posted at 4:36 PM, Jul 23, 2020
and last updated 2020-07-24 13:26:23-04

You may wonder what happens to people after they recover from COVID-19. Can a person get it again? Is there any natural resistance? After people are infected with the novel coronavirus, their natural immunity to the virus could decline sooner rather than later.

Antibodies are the proteins the body makes to fight infection and the CDC says their presence may tell you whether you have been infected with the coronavirus in the past. But new research suggests antibody responses may start to decline within a month from the time COVID-19 symptoms first emerge, according to William Haseltine, president of Access Health International.

"Now there are two studies, one from Spain and one from the UK, that actually measures the virus in people and the antibodies and watching the immunity decline," said Haseltine.

In one of the studies, released on a medical server and not yet been peer-reviewed, the researchers say those who have a severe form of COVID-19 may have longer-lasting antibodies than those with mild cases. But it is still only a matter of time before those antibodies wane.

They say the study has important implications when considering protection against re-infection and the durability of vaccines. Other experts point out w do not know for sure whether people can get reinfected with the coronavirus.

"If it were true that the antibodies and protection were only lasting 20 to 30 days, I think we'd start to see some significant amounts of re-infection," says Dr. Sanja Gupta, CNN Medical Correspondent.

The study suggests vaccines in development will either need to generate stronger and longer-lasting protection compared to natural infection, or they may need to be given regularly.