Single doses of the Pfizer and Moderna vaccines are more than 92 percent effective in preventing COVID-19 infection after two weeks, researchers from Canada now say.
The FDA’s own data show that one picture of the BioNTech-Pfizer vaccine is 92.6 percent effective after two weeks, and one Moderna injection is 92.1 percent effective, the researchers note in New England Journal of Medicine.
Having that second view of the Pfizer vaccine walked the effectiveness just a little bit, to 94 percent, according to a separate study based on real – world data from the Israeli vaccine program.
The second prescribed dose should therefore be given instead of those in priority groups still awaiting their first sight, “with the current vaccine shortage,” the load -researchers want.
“With the first dose so protective, the benefits of a scarce supply of vaccine could be enhanced by delaying second doses until at least one dose is offered to each member of the group. priority, ”the researchers say in a letter to the editors of NEJM.
“There may be uncertainty about the duration of protection with a single dose,” the researchers said.
“But administering a second dose within a month after the first, as suggested, does not provide much additional benefit in the short term, as long as there are potentially high-risk people. received the first dose with that vaccine supply left completely unprotected. ”
The letter was written by Dr. Danuta M. Skowronski of the British Columbia Disease Control Center in Vancouver and Dr. Gaston De Serres of the Institut National de Sante Publique du Quebec in Quebec City.
In a letter to NEJM in response to the two researchers, Pfizer stressed that “other dosing regimes” still need to be evaluated.