Single doses of the Pfizer and Moderna vaccines are more than 92 percent effective in preventing COVID-19 illness after two weeks, Canadian researchers are saying.

The FDA’s own data show that a single shot of the BioNTech-Pfizer vaccine is 92.6 percent effective after two weeks, and a single Moderna jab is 92.1 percent effective, the researchers note in the New England Journal of Medicine. //

“There may be uncertainty about the duration of protection with a single dose,” the researchers said.