The antibody response to COVID-19 reduces over just weeks to months.
Findings published by Imperial College London and Ipsos MORI today suggest that our antibody response to COVID-19 reduces over time following infection.
The REACT-2 study recruited over 365,000 participants in the largest antibody home surveillance study for COVID-19.
Selected adults tested themselves at home using a finger-prick test between 20 June and 28 September to check if they had antibodies against COVID-19.
Over this period, the proportion of people who tested positive for COVID-19 antibodies declined by 26.5%, suggesting antibodies reduce in the weeks or months after a person is infected.
The results also revealed that people who did not show symptoms of COVID-19 are likely to lose detectable antibodies sooner than those who did show symptoms and antibodies loss is slower in those aged 18 to 24.
Unclear what level of immunity antibodies provide.
Professor Paul Elliott, Director of the REACT programme at Imperial from the School of Public Health, said: “Our study shows that over time there is reduction in the proportion of people testing positive for antibodies against the virus that causes COVID-19.
“It remains unclear what level of immunity antibodies provide, or for how long this immunity lasts.
“If someone tests positive for antibodies, they still need to follow national guidelines including social distancing measures, getting a swab test if they have symptoms and wearing face coverings where required.”
Helen Ward, one of the lead authors of the antibody waning report, added: “This very large study has shown that the proportion of people with detectable antibodies is falling over time.
“We don’t yet know whether this will leave these people at risk of reinfection with the virus that causes COVID-19, but it is essential that everyone continues to follow guidance to reduce the risk to themselves and others.