While the Delta variant surges across the country, another mutation of COVID-19 is starting to spread among patients in Florida. Health care officials in Miami say the new variant—which is currently called B.1.621—now makes up about 10% of the cases there.
B.1.621 seems to have originated in Colombia and is likely spreading in South Florida because of the frequent travel between that country and Miami.
The variant, so far, has not been named one of concern or interest, as it accounts for just 2.1% of cases, according to the Washington Post. The European Center for Disease Control and Prevention, however, notes it could have significant impact, but cautions that right now data is preliminary. Public Health England continues to run lab tests on B.1.621.
News of the new variant comes as the CDC, in internal documents, warns that the Delta variant is as contagious as chicken pox and carries a longer transmission window than the original COVID-19 strain. Delta, the document says, is currently more transmissible than the common cold, the 1918 Spanish flu, smallpox, and Ebola.
While B.1.621 still makes up just a fraction of cases, Florida health care officials point out that the Delta variant accounted for a small percentage of cases two months ago and is now the dominant in the country, making up 83% of U.S. COVID cases. They’re increasing calls for people to get vaccinated and backing the CDC’s renewed call to wear masks indoors in areas of high infection.
The Centers for Disease Control and Prevention is currently monitoring 10 additional virus mutations beyond B.1.621.
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