LONDON: Catching and overcoming COVID-19 prevents symptomatic reinfection for the following six months, according to new research that will allay concerns that immunity to the virus drops rapidly after patients recover.
The study of over 11,000 healthcare workers in the British city of Newcastle found that nobody who tested positive for COVID-19 had re-developed symptoms several months later, suggesting that post-infection immunity lasts at least half a year.
The team of researchers from Newcastle University and Newcastle-Upon-Tyne Hospitals concluded that “infection appears to result in protection against symptomatic infection in working age adults, at least in the short term.”
Rapid reinfection with COVID-19 after recovery has been recorded, though it is uncommon. Previous studies have found instances in which people tested positive quickly after recovery, and there have been even rarer reports that some people have died after reinfection.
But those reports are difficult to corroborate, and the Newcastle study suggests that cases such as these are rarer than initially feared, boosting confidence that most people who recover from the disease will be afforded some level of protection in the months following.
The peer-reviewed study also carried out preliminary testing for asymptomatic cases, and found similar results suggesting strong immunity in the months following infection.
Due to limitations of the study, however, the researchers urged caution, saying they remain “uncertain” if previous infection confers complete protection against asymptomatic reinfection.
There is currently no clear verdict on whether asymptomatic cases pose an infection risk to others.