Here's how mRNA viruses like COVID-19 mutate, and why certain viruses are harder to develop vaccines for.
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Two major variants of the virus that causes COVID-19 have emerged in recent weeks, raising questions about their contagiousness and accuracy of testing. But neither is more dangerous than the virus that has circulated for the last year, experts say, and available vaccines should remain effective.
COVID-19 testing labs across the U.S. should be monitoring samples for mutated variants of the virus, the Food and Drug Administration said Friday. There is a chance the mutations will cause some tests to return false-negative results,the agency warned, though it's unlikely most tests will miss people who are contagious.
"The FDA believes the risk that these mutations will impact overall testing accuracy is low," according to the statement.
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