Multiple Covid-19 Vaccine Protections Pose Messaging Challenge

Varying protection levels in forthcoming Covid-19 vaccines could pose a messaging challenge for public health leaders racing to achieve high vaccination levels.

Johnson & Johnson Inc. released interim results Friday showing its vaccine was 66% effective in preventing severe and moderate cases of Covid-19, with a 72% protection level in the U.S. That’s lower than the 90%-plus efficacy rates of the Pfizer/BioNTech and Moderna vaccines currently in circulation.

“A 70% or 75% effective rate is still really wonderful. It is on par even above some of the other vaccines that we use all the time,” Katharine J. Head, an associate ...