The SIREN study has been regularly performing antibody and PCR testing on healthcare workers from 102 NHS trusts since June 2020.
The study found that antibody protection after infection lasts for at least five months on average, although the researchers are currently studying whether protection may last for longer.
They also found evidence that those with antibodies could still carry the novel coronavirus in their nose and throat and spread it to other people.
The SIREN study scientists also detected 44 potential cases of COVID-19 reinfections between 18 June and 24 November 2020…