A human B-cell. These are the immune system cells that make antibodies. | NIAID

A 25-year-old man in Nevada was confirmed to be reinfected with Covid-19.

Researchers at the University of Nevada have reported that a 25-year-old man was reinfected in June with SARS-CoV-2, the virus the causes Covid-19. He joins a handful of other confirmed cases of reinfection in people without immune disorders — in Belgium, the Netherlands, Hong Kong, and Ecuador — where researchers have demonstrated that the genetic signature of the second infection did not match that of the first.

According to a new study on the Nevada case, published in The Lancet Infectious Diseases journal, the patient first tested positive in April, and then tested negative for the virus twice. In June, 48 days later, “the patient was hospitalized and tested positive for a second time,” according to