By Chuks Ekpeneru
As some countries witness a second wave of the Coronavirus, a man in the United States has caught the disease a second time, with doctors saying this is far more dangerous than the first.
The 25-year-old Nevada, USA man needed hospital treatment after his lungs could not get enough oxygen into his body.
But the study in the Lancet Infectious Diseases journal raises questions about how much immunity can be built up to the virus.
Reports say he had no known health problems or immune defects that would make him particularly vulnerable to COVID-19.
Scientists say the patient caught coronavirus twice, rather than the original infection becoming dormant and then bouncing back. A comparison of the genetic codes of the virus taken during each bout of symptoms showed they were too distinct to be caused by the same infection.
“Our findings signal that a previous infection may not necessarily protect against future infection,” said Dr Mark Pandori, from the University of Nevada.
“The possibility of re-infections could have significant implications for our understanding of Covid-19 immunity.”
Dr Panfori urged people who have recovered should continue to follow guidelines around social distancing, face masks and hand washing.