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When people ask how to protect themselves against the spread of COVID-19, one of the first suggestions from doctors is washing your hands. Here are the do’s and don’ts.

USA TODAY

An otherwise healthy 25-year-old Nevada man is the first American confirmed to have caught COVID-19 twice, with the second infection worse than the first.

He has recovered, but his case raises questions about how long people are protected after being infected with the coronavirus that causes the disease, and potentially how protective a vaccine might be.

“It’s a yellow caution light,” said Dr. William Schaffner, an infectious disease expert at the Vanderbilt University School of Medicine in Nashville, Tennessee, who was not involved in the research.

Respiratory infections like COVID-19 don’t provide lifelong immunity like a measles infection. So, Dr. Paul Offit, an infectious disease expert at Children’s Hospital of Philadelphia, said he’s not at all surprised people