Coronavirus antibodies last for at least six months after infection for the majority of people who have had the virus, according to a new study.
It found that 99% of participants who had tested positive for a previous infection were kept Coronavirus antibodies for three months after becoming infected, while 88% did so during the full six months of the study.
UK Biobank research also found that 8.8% of the UK population had been infected as of December 2020, rising to 12.4% in London and 5.5% in Scotland.
He measured the levels of previous infection in various population groups across the UK as well as the duration of antibody persistence in those infected.
UK Biobank Chief Scientist Professor Naomi Allen said: “This important study has found that the vast majority of people retain detectable antibodies for at least six months after infection with the coronavirus.
“While we cannot be sure how this relates to immunity, the results suggest that people can be protected against further infection for at least six months after natural infection.
“Further follow-up will allow us to determine how long this protection is likely to last. ”
For the six-month period from late May 2020 to early December 2020, UK Biobank collected monthly blood samples and potential symptom data from 20,200 participants and their adult children and grandchildren.
The study also found that the proportion of the population with anti-Sars-CoV-2 antibodies (seroprevalence, which indicates past infection) increased from 6.6% at the start of the study period to 8.8. % at the end of it.
There was no gender difference, but the proportion of participants with detectable antibodies was highest among young people (13.5% among those under 30) and lowest among older people (6 , 7% among those over 70).
Past infection with Sars-CoV-2 (the name of the virus that causes COVID-19) was highest among ethnically black participants (16.3%) and lowest among those of white ethnicity ( 8.5%) and Chinese (7.5%).
The most common symptom associated with the presence of antibodies to the coronavirus was loss of taste and smell, which was reported by 43% of HIV-positive participants.
About a quarter (24%) of HIV-positive participants were completely asymptomatic and 40% did not have any of the three COVID-19 symptoms – fever, persistent dry cough, or loss of taste or smell.
However, the researchers warned that just because people have developed an antibody response doesn’t mean they still can’t pass the virus on to others.
UK Biobank lead researcher Professor Sir Rory Collins said this meant it was ‘important to keep social distancing and lockdown measures in line with government guidelines’.
He added that the results support the government’s decision to delay second doses of COVID-19 vaccines for up to 12 weeks.