A single dose of Pfizer’s vaccine may be less effective than the drugmaker had indicated, Israel’s COVID-19 czar has warned.
Nachman Ash — Israel’s equivalent of Dr. Anthony Fauci — said the protection offered by the first dose is “less effective than we had thought,” Army Radio reported.
“Many people have been infected between the first and second injections of the vaccine,” Ash said, adding that the protective effect appears “lower than [the data] presented by Pfizer.”
The pharmaceutical giant has claimed that trials show it is roughly 52 percent effective around 12 days after receiving the first shot, the BBC reported.
But that level of protection rises to 95 percent around two weeks after the second dose.
It’s unclear exactly how effective the shot has been for the more than 2 million Israelis who have already received the first dose.
Questions were raised about the vaccine’s performance after health officials on Monday announced 10,000 new cases, the highest since the pandemic began.
Experts have repeatedly warned that one dose of the vaccine doesn’t provide full immunity and that social distancing measures will still need to be in place to get the pandemic under control.