Corona virus symptoms such as a fever and persistent cough may not actually have the disease. Public Health England (PHE) researchers looked at 1,000 key workers who thought they had recovered from Covid-19 over summer after suffering the disease’s most common symptoms.
But 49 per cent of the participants tested negative for antibodies in their blood , proteins that signal a person has previously had the virus. This may be an underestimate of those who had actually infection because there are other parts of the immune system that fight the virus like, T cells, which are not detectable with tests.
Most people mount an antibody response. But antibodies wane over time, so might not show in tests. ‘In the course of this study, we tested just under a thousand people who thought they had had Covid-19 due to compatible symptoms,said Ranya Mulchandani, a field epidemiologist fellow at PHE. We found that half of them lacked any evidence of having had the infection, testing negative for the presence of antibodies.
Although these findings are still subject to peer review, it is possible that a large number of people in the general population incorrectly believe that they have already had Covid-19.
‘It is crucial that people do not get complacent and continue to observe government health advice, including social distancing and good hand hygiene, even if they think they have been infected in the past