People who have had COVID-19 are most likely to have immunity to it for at least five months, but there is evidence that people with antibodies may still be able to carry and spread the virus, a UK study of healthcare workers found.
Preliminary results from Public Health England (PHE) scientists showed reinfections in people with COVID-19 antibodies due to previous infection are rare – only 44 cases were found among 6,614 previously infected people in the study.
However, experts warned that the results mean that people who contracted the disease in the first wave of the pandemic in the first few months of 2020 may now be at risk to get it again.
They also warned that people with so-called “natural immunity” acquired through the infection could still carry the SARS-CoV-2 coronavirus in their nose and throat and inadvertently pass it on.
“We now know that most of those who had the virus and developed antibodies are protected from re-infection, but this is not complete and we don’t yet know how long the protection will last,” said Susan Hopkins, senior medical advisor at PHE and co-leader of the study, the results of which were published Thursday.
“This means that even if you think you have had the disease and are protected, you can be assured that there is a very unlikely chance that you will develop serious infections, but there is still a risk that you will acquire an infection and get it transferred to others. “
A statement accompanying the study said the results did not address antibodies or other immune responses to vaccines currently being rolled out against COVID-19, or how effective vaccines would be. Vaccine reactions are being considered later this year, it said.
Known as the SIREN study, the study involved tens of thousands of healthcare workers in the UK who have been regularly tested for new COVID-19 infections as well as for the presence of antibodies since June.
Between June 18 and November 24, scientists discovered 44 potential reinfections – two “likely” and 42 “possible” – out of 6,614 participants who tested positive for antibodies. This corresponds to a protection rate of 83% against renewed infection.
The researchers plan to follow up and evaluate participants to see if this natural immunity lasts longer than five months in some cases. However, they cautioned that early evidence from the next phase of the study suggests that some people with immunity still carry high levels of the virus and can pass them on to others.
“It is therefore crucial that everyone continues to follow the rules and stay at home even if they previously had COVID-19,” they said in the statement on their results.
(This story was not edited by GossipMantri staff and is automatically generated from a syndicated feed.)