The United States should rapidly deploy Covid-19 vaccines and step up surveillance before highly contagious variants emerge or the virus re-mutates and makes the pandemic worse, said CDC director Dr. Rochelle Walensky Wednesday.
Three variants first identified in the UK, South Africa and Brazil have caused researchers some concern, according to a research opinion she wrote with Dr. Anthony Fauci, White House Chief Medical Advisor. A CDC study published in January warned that the variant found in the UK, known as B.1.1.7, is likely to become the dominant species circulating in the US in March.
The B.1.1.7 variant has proven to be highly transferable and “preliminary data suggests the possibility of increased disease severity with infection,” wrote Walensky, Fauci and Dr. Henry Walke, the CDC’s Covid incident manager, in the published position. Wednesday in the Journal of the American Medical Association, aka JAMA.
Walensky told JAMA in a separate interview on Wednesday that the variant is expected to be about 50% more transmissible than previous strains and early data suggests it could be up to 50% more virulent or deadly.
“Model data has illustrated how a more contagious variant, such as B.1.1.7, could accelerate the trajectory of the US pandemic and reverse the current downward trend of new infections and further slow pandemic control,” said Walensky . said in the newspaper.
So far, the US has identified at least 1,277 Covid-19 cases with the B.1.1.7 variant from the UK19 of the B.1.351 variant, which was discovered in South Africa, and three cases of the P.1 variant found in Brazil, according to recent data from the CDC.
Surveillance for the variants at a commercial lab in early February suggests that the prevalence of the B.1.1.7 variant nationwide is likely approaching 1%, although the prevalence could be more than 2% in some states, according to the paper.
However, the more the virus circulates and infects other people, the more likely it is to mutate. That’s part of why global health experts have been pushing people to redouble their public health measures, such as social distancing, washing hands regularly and wearing masks, until vaccines can be deployed and populations can achieve so-called herd immunity.
A faster-spreading virus would also mean more people should be vaccinated to build an umbrella of immunity, experts said. In the US, the level of viral spread in the community must be “aggressively reduced,” and Americans must delay travel and avoid crowds to make sure the variants don’t continue to spread, top federal health officials wrote in their position.
“The more they mutate, the more likely we will see dominant variants that can really emerge and become a problem for us,” Walensky told JAMA. “So the best we can do to prevent these in general is to circulate fewer diseases and circulate fewer viruses.”
Surveillance is missing
The country’s response must not only relate to the variants found in the UK, South Africa and Brazil, but it must also be willing to detect mutations that can occur inland, Walensky said.
The country’s infrastructure to perform “genome sequencing” for the variants in the US has so far been insufficiently prepared to detect the circulating strains.
The CDC is working with public health and commercial laboratories to rapidly scale up the country’s genomic sequencing. In January, the US analyzed just 250 samples per week for the variants, which have since grown to “thousands,” Walensky said. However, she added that “we are not where we need to be.”
“It’s going to be a dial, not a switch, and we have to call him,” Walensky said.
This is a story in progress. Check back later for updates.