A 33-year-old man has contracted COVID-19 after recovering from the illness earlier this year in what’s believed to be the world’s first case of reinfection, researchers announced Monday.
University of Hong Kong researchers said the man tested positive for the virus again at the airport this after returning from a trip to Spain, the Japan Times reported.
“An apparently young and healthy patient had a second case of COVID-19 infection which was diagnosed 4.5 months after the first episode,” researchers said, according to the New York Times.
Using sequence analysis, researchers determined that his strain of the virus appeared to be the same one spreading around Europe this summer.
“Our results prove that his second infection is caused by a new virus that he acquired recently rather than prolonged viral shedding,” said Dr. Kelvin Kai-Wang To, who is a clinical microbiologist at the university.
Doctors have previously reported cases of presumed reinfection, but the case has been the first to be confirmed through scientific testing.
The evidence could have important implications for how experts understand coronavirus antibodies, researchers said.
“Before this report, many believe that recovered COVID-19 patients have immunity against re-infection, however, there is evidence that some patients have a waning antibody level after few months,” the researchers wrote in a statement, according to the Japan Times.
