According to a new study, one dose of the Pfizer/BioNTech vaccine is nearly as effective as two.
One dose of the Pfizer/BioNTech COVID-19 vaccine is 85 percent effective in preventing symptomatic disease 15 to 28 days after being administered, according to a new study reported in The Lancet. Currently, the Centers for Disease Control and Prevention (CDC) recommends that the U.S. stick to the two-dose regimen with vaccinations occurring 21 days apart, the approach that was tested in clinical trials and approved by the Food and Drug Administration (FDA). That dosing regimen provides 95 percent protection against the virus. The CDC recently advised that waiting up to 42 days between the first and second doses would be OK. The new study bolsters an analysis by other researchers published in The New England Journal of Medicine (NEJM) that estimated that one shot of the Pfizer/BioNTech vaccine is 92.6 percent effective after two weeks. The same researchers also found that one dose of Moderna’s COVID-19 vaccine is 92.
