The COVID-19 variants first discovered in the UK and South Africa and now circulating worldwide do not pose a current threat into the effectiveness of the first vaccines, but mutations will be closely monitored because “they could be a problem,” NIAID director Anthony Fauci told Axios.
The big picture: Vaccinations are underway, albeit with a slow start. The goal of returning to normal depends on achieving 70% -85% immunity of the herd in the population, Fauci says. While there are some concerns that the mutations could bypass the vaccines, he says they’re more of a problem for certain treatments than for vaccines.
What is going on: Viruses often mutate, but often those changes are small and not cause problems with treatments or vaccines. Public health officials have been closely monitoring the SARS-CoV-2 variants.
B.1.1.7 does not appear to be more virulent or to overcome the effect of the vaccine, based on what British doctors say, Fauci says.
- B.1.1.7 is more transmissible because it binds more easily to the ACE2 receptor, the way the virus enters cells.
- That increases the need for faster vaccinations, says Carlos del Rio, a leading professor of medicine at Emory University School of Medicine.
- “If the R-zero goes from 2.5 to 2.9 in a totally naïve population, after 10 cycles of transmission, instead of 9,000 infected people, you have 42,000 infected people,” warns del Rio.
The 501.V2 variant is “a little more concerned about the possibility of interference with some of the monoclonal antibodies,” based on preliminary findings, Fauci says.
- Monoclonal antibody treatments target exactly one specific area of the virus, and “if the mutation happens to be in that epitope, it could prevent the effect of the treatment,” he says.
- In contrast, vaccines “elicit a polyclonal response against multiple different aspects of the spike protein,” Fauci emphasizes. “To really get around the vaccine’s effectiveness, there must be many mutations that are all in the right place. “
What they look at: Scientists monitor the strains and test them against the vaccines.
- “If it doesn’t affect the vaccine, you are good to go. If it does, you have to make a few minor adjustments to the vaccine to get around the changes that occur in the mutations,” Fauci says.
- With the ‘plug-and-play’ nature of the mRNA vaccines, it is much easier to change the composition of those vaccines, he adds.
- And because there is now a large amount of data on the mRNA-based vaccine platform, “it is likely that the FDA will consider it just a strain change that does not have to start with the first,” he says.
It comes down to: “You always have to take these things seriously, follow them closely, and hope there won’t be a problem. But if that’s the case, you have to adapt to them,” says Fauci. “And now we have the technology to do that quite easily.”