Dr. Fauci warns that delaying the second dose of the Covid vaccine will provide “small” protection against mutants that may weaken the injection.
- UK health officials allow a second dose to be delayed for up to 12 weeks
- Dr. Fauci opposes this strategy in the United States, saying there is no “right or wrong” dosing approach when purchased on Monday.
- A single dose of vaccine made by Moderna or Pfizer seems to be 80% effective
- However, he said it was unclear how long the protection would last, and that more infectious variants could administer vaccinated people to “lean zones.”
Dr. Forch is concerned that people who are not “fully affected” by a double dose of the vaccine will be dangerously vulnerable to infection by mutants that weaken the effect of the antibody.
Currently, more than 40% of adults in the United States have been vaccinated at least once, but cases have increased for the fourth straight week.
“We know that these increases are in part due to the more infectious mutations we are monitoring very closely,” said the Centers for Disease Control and Prevention (Centers for Disease Control and Prevention.CDC) Monday director Rochelle Warrensky White House briefing.
Her warning is that while extending these timelines allowed the United Kingdom to speed up ahead of the United States in vaccination races, Americans have both Pfizer and Moderna vaccines. He emphasized Dr. Forch’s concern that doses should be obtained on time.
Dr. Anthony Fauci warned on Monday that people who received only one Covid vaccine made by Moderna or Pfizer would have “small” protection against the mutants.
In the UK, a second dose of the Pfizer or AstraZeneca vaccine may be delayed by up to 12 weeks.
This strategy, which was controversial when it was first introduced, has helped the UK to some extent protect nearly half of its population with one or more vaccinations.
At the time, Dr. Fauci rejected and even criticized Britain for adopting an untested strategy (although he later receded his harsh words).
But on Monday, he said there was no “right or wrong” strategy when it came to delaying the dose.
“There are different approaches and different opinions,” he said.
“We can say that the level of protection after a single dose is 80%, but we are concerned that it is somewhat dilute, for example due to the level of neutralizing antibodies. Against the coronavirus, the question is how long it will last when you leave it alone in a single dose.
According to a study published last month, the risk of getting COVID-19 after the first dose of the Pfizer or Moderna vaccine was reduced by about 80% within two weeks of the first injection.
However, the second dose is given one or two weeks later, depending on whether you have obtained a Pfizer vaccine with a dosing regimen with a 3-week gap or a modeler that should be given after 4 weeks. I did.
It remains unclear how a single dose after that second week will protect people.
And with the variants in circulation, all protection is important.
Both vaccinations are still defensive against vaccine avoidance mutants from Brazil and South Africa.
However, the antibodies produced by these vaccines are two to six times less effective at binding to peplomer, which allows coronavirus to invade human cells.
Therefore, in Dr. Fauci’s view, leaving more people with the first dose alone for longer may not be worth the risk.
Neither variant is common in the United States, so Americans are unlikely to encounter them.
So far, South African and Brazilian variants each account for less than 0.05% of Covid cases in the United States. Outbreak.info..
Still, they are substantially more infectious than “wild-type” viruses, and experts are worried that they will only become more prevalent.
Fauci: A single dose may be a “lean” defense against mutants
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