Is one dose of corona vaccine enough??

The first coronavirus vaccines being made worldwide raised hopes of a breakthrough in the fight against COVID-19, but experts are now raising an even more optimistic possibility: People may only need one dose instead of the current two-dose regimen.

But the idea has sparked scientific controversy, with experts saying there isn't enough evidence yet to justify a single dose and people should plan to get two.

Opinions in favor of exploring the idea of ​​a single-dose vaccine were crystallized in a recent opinion article in newspaper The New York Times for Michael Mina, an immunologist at Harvard University, and Zeinab Tawfiqi, a sociologist who has written extensively on the epidemic.

And they called for the immediate start of a new clinical trial to study whether a single dose of the vaccine is sufficient. They cite data from trials already conducted with the Pfizer and Moderna vaccines that showed protection started after the first dose, with efficacy up to about 90%, compared to about 95% after two doses.

However, questions were raised about how long the protection would last without the second booster dose, but Mina and Tawfiqi wrote that the possibility of needing a single booster dose should be immediately considered.

According to the article, “If this proves to be the case, it will be a game-changer, allowing us to vaccinate up to twice as many people and greatly alleviate suffering not only in the United States, but also in countries where vaccine shortages may take years to resolve.

However, part of the question remains how effective it will be to go ahead with one dose rather than two even though the single-dose regimen would spread protection to twice the number of people at a time when about 2500 Americans on average die from the virus every day, especially since vaccines are not on the right track. To be widely available for several months.

“What can we do now that we don't have 60 dead in a month?” says Christopher Gill, professor of global health at the Boston University School of Public Health. And he answered: There should at least be a discussion about vaccinating twice as many people with a single dose immediately without waiting for a new trial. And if you wait, you may be dead.”

Scott Gottlieb, a former commissioner of the Food and Drug Administration (FDA), has questioned the administration's strategy of withholding half the doses to make sure there's enough for everyone to get their second dose, given that in the worst cases a single dose is still at least partially fine.

Assistant Secretary of Health and Human Services Brett Giroir said the administration is booking 2.9 million doses to serve as the second dose for the 2.9 million people vaccinated in the first week rather than spreading all of the doses at once.

"We know the first dose is partially protective, and the data isn't available right now, so you want to try to push as many doses as possible to give as many doses as possible," Gottlieb, now a member of the Pfizer board of directors, told CNBC earlier this month. People have some benefits.”

Other experts, including those on the Operation Warp Speed ​​team and the FDA, object to those proposing a single dose rather than two, noting that months of careful study of the two-dose regimen has been done.

"The second dose is a full part of the vaccine if the vaccines are approved," said Moncef Al-Salawi, chief scientific advisor to Operation Warp Speed, in a press conference. It boosts immunity in patients against COVID-19, and this is the data that shows long-term immunity and I expect it to be long-term so people should not take the vaccine as a single-dose vaccine.”

However, he left the door open for further study. One might ask the question, why aren't trials conducted on a single dose of Moderna or Pfizer? That would be a valid question, and of course, timing would be a huge challenge.