New information exhibits that Covid vaccines in opposition to some strains could also be much less efficient

New data shows that the Covid-19 vaccines currently on the market may not be as effective against new, more contagious strains of the coronavirus, giving “all the more reason” to vaccinate people faster, according to White House Health Advisor Dr . Anthony Fauci said on Thursday.

A handful of new strains of the coronavirus have emerged overseas, giving scientists cause for concern. Some variants identified in the UK, South Africa, and Brazil appear to be more transmissible than previous strains, but not necessarily more deadly.

While it’s no surprise that the virus is mutating, researchers are quick to figure out what the changes could mean for recently developed life-saving vaccines and therapeutics for the disease.

Some early results, published on the bioRxiv preprint server and not yet peer-reviewed, indicate that variant 501Y.V2 identified in South Africa may evade the antibodies of some coronavirus treatments and reduce the effectiveness of the current line of available vaccines.

“In addition, 501Y.V2 shows significant or complete leakage of neutralizing antibodies in COVID-19 convalescent plasma,” wrote researchers at the National Institute for Communicable Diseases in South Africa. Their conclusions, they said, “highlight the prospect of re-infection … and may anticipate decreased effectiveness of current spike-based vaccines.”

Even if the drugs are less effective, they will likely still provide enough protection to make the vaccines worthwhile, Fauci said during a White House press conference.

Both Pfizer and Moderna vaccines have been shown to be highly effective, providing approximately 95% protection against infection, creating a “cushion effect” that allows some decrease in their effectiveness.

“We’re following the one in South Africa very closely, which is a little more worrying, but nothing that we don’t think we can handle,” said Fauci.

A decline in the effectiveness of vaccines would be “all the more a reason why we should vaccinate as many people as possible”. Mutations occur when the virus spreads and replicates, which can be suppressed if enough people are vaccinated against the disease to build what is known as herd immunity, he explained.

“Bottom line: We’re very careful. There are alternative plans if we ever need to modify the vaccine. It’s not a very burdensome thing, we can do it given the platforms we have,” said Fauci.

World Health Organization vaccination director Kate O’Brien said Friday that it was too early to get clear information on whether the emerging variants will affect any of the current vaccines. O’Brien added that not every variant behaves the same, and the answer depends on the type of mutation and the vaccine.

“This is really evolving information, and there are a number of ways that assessments can be conducted to understand whether or not … the vaccine is less effective against the variants,” O’Brien said during a news conference.

Dr. Rochelle Walensky, the new director of the Centers for Disease Control and Prevention, said Tuesday that while the vaccines will work against the mutated variants, they may not be as effective as clinical trials.

“I am very optimistic about what these variants will look like,” said Walensky in an interview with the JAMA Network. “I could be wrong. We might find variants and variants pop up … where the vaccine is less effective, but I’m still optimistic right now.”

Early dates

To date, the United States has not detected any cases of Covid-19 with the strain identified in South Africa, Fauci said, although he added that the level of surveillance for the strains is “not what we would have liked”.

Research on the new variants is preliminary and limited.

The National Institute for Communicable Diseases used the blood samples from 44 people who previously had Covid-19 to see if their antibodies were effective against variant 501Y.V2. The study found that almost half of the cases, the neutralizing antibodies were not effective against the new variant, suggesting that people may be susceptible to re-infection.

The researchers noted that more large-scale clinical trials will be needed to determine the outcome of the vaccines. They added that “the speed and extent of 501Y.V2-mediated immune escape from pre-existing neutralizing antibodies highlights the urgent need for rapidly adaptable vaccine design platforms.”

Another study by Rockefeller University, which was not peer-reviewed, used blood samples from 20 people who had been vaccinated against Covid-19 with either Moderna’s or Pfizer’s regimen and tested their antibodies against the various mutations. The researchers found that for some mutations, the antibodies did not work as well, adding that the mRNA vaccines “may need regular updates to avoid possible loss of clinical effectiveness”.

“It’s a little different, but it’s definitely a difference,” said Dr. Rockefeller’s Michel Nussenzweig, who led the study, told Associated Press.

However, a study by Pfizer and BioNTechs scientists printed in bioRxiv found that their Covid-19 vaccine is likely just as effective against the mutated, infectious strain discovered in the UK. The US has identified at least 144 cases with this variant, far according to the latest data from the CDC.

The study’s authors warned that the rapid spread of Covid variants around the world required “continuous monitoring of the importance of changes to sustained protection from currently approved vaccines”.

– CNBC’s Reuters, Associated Press and Sam Meredith contributed to this report.