(CN) — Days after Moderna announced that its Covid-19 vaccine works to neutralize coronavirus strains found in the United Kingdom and South Africa, the good news was tempered by an inevitable discovery: The South Africa variant has been detected for the first time in the United States.
Two cases of the variant were diagnosed in South Carolina, state health officials said Thursday. The cases are not connected to each other, and neither of the infected individuals had traveled recently.
That means the variant is “probably more widespread,” said Dr. Krutika Kuppalli, an infectious diseases physician at the Medical University of South Carolina in Charleston, as quoted by the Associated Press.
Virus variants that transmit more readily, including the South Africa strain and the one from the U.K., which is believed to be up to 50% more transmissible, can take over existing strains, since they offer viruses a survival advantage.
Earlier this month, the Centers for Disease Control and Prevention announced that the U.K. variant, called B.1.1.7, will likely become dominant in the U.S. by March.
The variant from South Africa, called B.1.351, was first detected in October. It is also expected to be more highly transmissible.
Neither variant is expected to be more fatal, but the higher transmission rates carry concerns that hospitals may become overwhelmed by a jump in new Covid-19 cases, leading to more deaths.
In a moment of good news, Moderna said on Monday that its vaccine showed “neutralizing titers” against both U.K. and South Africa strains, and that the vaccine showed no reduction in antibodies against the new strains.
The company is also researching whether an additional booster shot can increase vaccine efficacy against new strains, and is working to tweak one shot to address the variant from South Africa specifically.
It’s common for viruses to create new versions of themselves, or variants, explained Dr. Brannon Traxler, interim public health director for the South Carolina Department of Health & Environmental Control.
The first official detection of the South Africa variant in the U.S. is “yet another reminder that the fight against this deadly virus is far from over,” Dr. Traxler said.
She encouraged people to continue physically distancing and wearing masks.
Health officials agree those measures remain paramount for slowing the spread of Covid-19 while a fragmented, state-by-state vaccine distribution effort persists. Fewer than 22 million people have received one or more doses, according to CDC data.
While virus mutations happen frequently, the CDC is particularly focused on three strains: those from the U.K., South Africa and a third variant, detected in travelers from Brazil during routine screening at an airport in Tokyo.
All three have now been discovered in the U.S. The country’s first case of the Brazil variant was announced on Monday, found in a Minnesota patient who had recently traveled to Brazil.
The CDC is continuing to survey genetic material from viruses to track mutations as they occur.
“We know that viruses mutate to live and live to mutate,” Dr. Traxler said.
Reducing the number of people who become infected with the coronavirus, however, also lowers the opportunities for the virus to evolve.
Wearing masks, keeping 6 feet apart from others, avoiding crowds, washing hands, getting tested and — when possible — vaccinated, therefore, remain "the best tools for preventing the spread of the virus, no matter the strain,” Dr. Traxler said.Follow @NinaPullano
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