New data on COVID-19 vaccines should serve as a “wake-up call” about the need to stop the spread of the SARS-CoV-2 virus among people and thus deprive it of opportunities to evolve its defenses, the top federal expert on infectious diseases said.
“The virus will continue to mutate and will mutate for its own selective advantage,” said Anthony S. Fauci, MD, director of the National Institute of Allergy and Infectious Diseases, at a Friday news conference organized by the White House.
The continued transmission of SARS-CoV-2 “gives the virus the chance to adapt to the forces, in this case the immune response, that’s trying to get rid of it,” Dr. Fauci said. “That’s where you get mutations.”
Federal health officials are working to boost the U.S. supply of COVID-19 vaccines, even as signals emerge about the extent that the virus is already evolving.
Data released this week about the Janssen/Johnson & Johnson (J&J) and Novavax COVID-19 vaccines in late-stage development provides further evidence that they may not protect as well against emerging variants, Dr. Fauci said.
“Mutations that lead to different lineage do have clinical consequences,” he said, while also emphasizing that the emerging vaccines appear to confer broad protection. Dr. Fauci earlier in the day addressed the “messaging challenge” for clinicians and researchers in discussing the results of the J&J vaccine trial, which appear to fall short of those reported for the two vaccines already approved and in use in the United States. He noted the benefits of possibly soon having more authorized vaccines to combat COVID-19. But continued community spread of the infection will foster conditions that can undermine the vaccines’ effectiveness.
“Even though the long-range effect in the sense of severe disease is still handled reasonably well by the vaccines, this is a wake-up call to all of us,” Dr. Fauci said.
Pharmaceutical scientists and executives and government health officials will need to work together to continue to develop vaccines that can outwit the emerging variants, he said.
On Jan. 29, J&J reported that its highly anticipated single-dose vaccine had shown its worst results in South Africa where many cases of COVID-19 were caused by infection with a SARS-CoV-2 variant from the B.1.351 lineage. The overall efficacy was 66% globally, 72% in the United States, and 57% in South Africa against moderate to severe SARS-CoV-2, J&J said.
Novavax on Jan. 28 reported an efficacy rate for its COVID-19 vaccine of 49.4% from a clinical trial conducted in South Africa, compared with an 89.3% rate from a U.K. study. There already have been attempts to estimate how well the Pfizer/BioNTech and Moderna vaccines can handle new variants of the virus. They both have been granted emergency-use authorization by the U.S. Food and Drug Administration.
The Centers for Disease Control and Prevention on Thursday reported the first U.S.-documented cases of the B.1.351 variant of SARS-CoV-2 in South Carolina. On Jan. 26, the first confirmed U.S. case of a highly transmissible Brazilian coronavirus variant was detected in Minnesota, state health officials said.
The CDC’s stepped-up “genomic surveillance” will help keep clinicians and researchers aware of how SARS-CoV-2 is changing, Dr. Fauci said.
Speaking at the same White House news conference, CDC director Rochelle Walensky, MD, MPH, said the two South Carolina cases of the B.1.351 variant were reported in different parts of the state and not believed to be epidemiologically linked. The people involved “did not have any travel history,” she added.
The SARS-CoV-2 mutations were expected to emerge at some point, as with any virus, but their appearance underscores the need for people to remain vigilant about precautions that can stop its spread, Dr. Walensky said.
She and Dr. Fauci both stressed the need for continued use of masks and social distancing and urged people to get COVID-19 vaccines as they become available. Continued community spread of the virus allows this global health threat to keep replicating, and thus increases its chances to thwart medical interventions, Dr. Fauci said.
“The virus has a playing field, as it were, to mutate,” Dr. Fauci said. “If you stop that and stop the replication, the viruses cannot mutate if they don’t replicate.”
A version of this article first appeared on Medscape.com.