At least four new variants of the coronavirus keep scientists awake at night.
One of them, first identified in the south-east of England, has now appeared in at least 50 countries and appears to be spreading more efficiently than older variations of the virus. Its appearance has frightened political leaders, who have closed borders and imposed travel restrictions to try to curb their spread.
Others, identified in South Africa and Brazil, have not traveled that far, but show a constellation of mutations that have caught the attention of geneticists.
B.1.1.7: At the top of the list for U.S. researchers is variant B.1.1.7, which was first seen in Britain. U.S. Centers for Disease Control and Prevention warned last week that it could worsen the spread of the pandemic.
While there’s nothing like the phrase “new mutant virus” that catches your eye, scientists say so far they are reassured by what they’ve found: the human immune system can manage the variants that have emerged so far.
B.1.351: A variant first seen in South Africa called B.1.351 or 501Y.V2, has a different mutation pattern that causes more physical alterations in the structure of the ear protein than B.1.1.7. An important mutation, called E484K, appears to affect the receptor binding domain, the most important part of the spike protein to bind to cells.
P.1 and P.2: Two variants of concern have first appeared in Brazil. One, called P.1., Was found in 42% of copies of a survey conducted in the Brazilian city of Manaus, and Japanese officials found the variant in four travelers from Brazil. The P.2, which was also first seen in Brazil, sparked an alarm when 11 people appeared in Britain last week.
L425R: Finally, a new variant called the L425R is seen in California, and although it is commonly found, it is still unclear whether it is more transmissible.
Read more about the variants:
