Researchers in Shanghai hope to determine whether some recovered coronavirus patients
have a higher risk of reinfection after finding surprisingly low levels of Covid-19 antibodies in a number of people discharged from hospital.

A team from Fudan University analysed blood samples from 175 patients discharged from the Shanghai Public Health Clinical Centre and found that nearly a third had unexpectedly low levels of antibodies.

In some cases, antibodies could not be detected at all.

“Whether these patients were at high risk of rebound or reinfection should be explored in further studies,” the team wrote in preliminary research released on Monday on Medrxiv.org, an online platform for preprint papers.