A research team at the University of California, Los Angeles, did an in-depth study of 34 people who had recovered from mild COVID-19 infections. They tested their blood two or three times over three months, Xinhua news agency reported on Tuesday.
The findings raise concern that humoral immunity against SARS-CoV-2 may not be long lasting in persons with mild illness, who compose the majority of persons with COVID-19, said the study.
Further studies will be needed to define a quantitative protection threshold and rate of decline of antiviral antibodies beyond 90 days, according to the study.
Source: IANS