Delaying second hit of COVID-19 could lead to more dangerous variants

• Dr Anthony Fauci on Monday warned against postponing the second COVID-19 shootings.
• He said it could be a recipe for new variants to spread by giving people weaker immunity.
• While one shot gives “some” protection, the data suggests that two shots are “tenfold” better, Fauci said.
• Visit Insider’s Business section for more stories.

Dr Anthony Fauci said ensuring that people in the United States receive their second dose of a Pfizer or Moderna COVID-19 vaccine on time could be of critical importance in curbing the rise of new virus variants to rapid spread.

Fauci, director of the National Institute of Allergy and Infectious Diseases, said that while it was true that a single shot could “give a certain degree of protection” to people, it seemed far from so stronger than the mighty shield of disease provided by two planes.

That is why he does not recommend giving more Americans the first doses of the vaccine and waiting until later in the year to give people their second “booster” injection, a strategy that is currently being tested in the Kingdom. -United.

This plan, while it may succeed in partially protecting more people faster, is just too risky and not supported by any of the data we have so far, he said.

“The way viruses react to pressure, you might actually inadvertently select more mutants,” Fauci said Monday during a coronavirus briefing at the White House. “For this reason, we have continued to accept that we believe the optimal approach would be to continue to receive as many people as possible for their first dose, but also to make sure that people – on time – receive their. second dose.

2 injections provide enhanced protection against all forms of the virus, including variants

Patrick Semansky-Pool / Getty Images

Vaccine trials with tens of thousands of volunteers around the world have shown how well the licensed vaccines from Pfizer and Moderna work as a two-dose course when given 21 days apart (for Pfizer) or 28 days apart (for Moderna).

In this way, these vaccines appear to be over 90% effective in stopping symptomatic coronavirus infections. (AstraZeneca’s two-dose vaccine, approved for use in the UK but not yet in the US, appears to be less effective than that of Pfizer and Moderna.)

Two injections of the vaccine from Pfizer or Moderna, when given on time, can provide “ten times” the immune protection at one go, Fauci said.

“The reason this is important is not just because of the height of the response and the power of the response, but when you reach that level of antibody you get a greater magnitude of response,” Fauci added.

This “scale” of the viral response could be of crucial importance in helping to curb the pandemic, especially at this time.

“By breadth of response we mean that it covers not only the wild type and virus currently in circulation, but also the variants that we see circulating, particularly 1.1.7 and 3.5.1,” Fauci added. , referring to the variants first identified in the UK and South Africa, respectively.

In other words, since vaccines don’t work as well against the newer variants, it’s important to make sure that the coverage we get from them is as strong as possible, and the way to do that is to give people two full injections.

It seems increasingly likely that the B.1.1.7 variant will become the dominant strain of the virus transmitted to the United States by March, Fauci said – a timeline that matches recent predictions from other experts.

We still don’t know if we could ‘get away with just one dose’

Hans Pennink / AP

Fauci said it was still “not unreasonable” to wonder if people could “get away with a single dose” of Pfizer or Moderna vaccines, at least for a little while.

But he stressed that there were no final studies on the effectiveness of this one-off strategy. By the time rigorous testing on the matter could be completed, there would be a better supply of vaccine across the United States anyway, making it a “moot point” for the study, he said. said.

The strategy could also be dangerous.

One injection of Moderna or Pfizer vaccine will provide a lower degree of anti-infective potency than two full doses. As a result, Fauci said, giving people a single dose could turn their vaccines into easier-to-fight threats for the virus, allowing it to learn how to mutate faster and better and to continue infecting more vaccinated people.

The important thing, Fauci said, is to “get as many people vaccinated as possible as quickly as possible” with two injections.

“It’s the best defense against the evolution of variants,” he said.