A new “double mutant” coronavirus strain believed to be behind a surge of cases in India has been discovered in San Francisco, marking what is thought to be the first time the variant has been detected in the U.S.
The strain is referred to as a “double mutant” because it carries two mutations that help the virus latch onto cells, the San Francisco Chronicle notes.
The variant, like strains from the United Kingdom and Brazil, is believed to be more transmissible than the pre-existing form of the virus. It is currently unknown whether the "double mutant" strain is more resistant to vaccines available in the U.S.
“This Indian variant contains two mutations in the same virus for the first time, previously seen on separate variants,” Peter Chin-Hong, an infectious diseases expert at the University of California San Francisco, told the Chronicle.
“Since we know that the domain affected is the part that the virus uses to enter the body, and that the California variant is already potentially more resistant to some vaccine antibodies, it seems to reason that there is a chance that the Indian variant may do that too,” Chin-Hong added.
Chin-Hong said that he was “optimistic” that vaccines would be effective against the “double mutant” strain, given data showing vaccines are effective against similar strains that were first detected in South Africa and California.
Health experts have warned that the U.S. could be heading into a fourth wave of coronavirus cases fueled by new, more infectious strains. However, other experts, such as former Food and Drug Administration Commissioner Scott Gottlieb, have predicted that existing immunity coupled with the rise in vaccine administration may stave off a "true fourth wave" of cases in the U.S.
According to the Centers for Disease Control and Prevention, California has administered nearly 20 million doses of coronavirus vaccines. The state is scheduled to open vaccine eligibility to everyone over 16 beginning on April 15. The U.S. recently hit a new record in administering over 4 million doses of coronavirus doses in a day. As of Monday, 32 percent of the U.S. population has received at least one dose.