At least 14 sailors aboard the USS Theodore Roosevelt who had recovered from COVID-19 have tested positive for a second time, raising questions about immunity and whether people can catch the coronavirus shortly after getting better, NBC News reports.
The sailors who "previously tested COVID positive and met rigorous recovery criteria have retested positive," a U.S. Pacific Fleet spokesperson said in a statement. The sailors are now off the ship and are required to isolate for at least 14 days.
Experts said the perplexing test results don't necessarily establish that a person can become infected twice — the positive results following negative tests may be a quirk related to the type of test that was used.
Nearly all of the diagnostic tests for COVID-19 in the U.S. look for snippets of the virus' RNA, or genetic code. (Another type of diagnostic test, called an antigen test, looks for proteins from the virus.)
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