About three-fourths of people infected in a recent Massachusetts Covid-19 outbreak were fully vaccinated against the virus, with four of them requiring hospital treatment, according to new data published Friday by the Centers for Disease Control and Prevention (CDC).
The new data, published in the U.S. agency’s Morbidity and Mortality Weekly Report, also reveals that fully vaccinated people who get infected carry as much of the virus in their nose as the unvaccinated and could spread it to other individuals just as easily.
“This finding is concerning and was a pivotal discovery leading to CDC’s updated mask recommendation,” CDC Director Dr. Rochelle Walensky said in a statement. “The masking recommendation was updated to ensure the vaccinated public would not unknowingly transmit virus to others, including their unvaccinated or immunocompromised loved ones.”
On Tuesday, the CDC changed course on its prior guidance and recommended fully vaccinated Americans who live in places with high infection rates to resume wearing face masks indoors.