The case of a man who has been infected with covid-19 twice in the United States shows that there is still a lot to learn about immune reactions, and also raises doubts about vaccination, scientists said on Tuesday.
The 25-year-old man from Reno, Nevada, was diagnosed in April after showing mild symptoms, and came back more seriously in late May, according to a case report from the scientific journal Lancet Infectious Diseases.
The report was published just hours after U.S. President Donald Trump, who was infected with covid-19 and hospitalized earlier this month, said he believed he was immunized and that he felt “very powerful”.
Scientists said that while incidences of reinfection seem rare – and the Nevada patient is already recovered – cases like yours are worrying. Other isolated cases of reinfection have been reported worldwide, including in Asia and Europe.
“It is becoming increasingly clear that reinfections are possible, but we still cannot know how common this will be,” said Simon Clarke, microbiology experts at Reading University in the United Kingdom.
“If people can easily re-infect themselves, this could also have implications for vaccination programs, in addition to our understanding of when and how the pandemic will end.”