The Evidence Cited by the CDC Does Not Show That Vaccinated and Unvaccinated COVID-19 Carriers Are Equally Likely To Transmit the Virus
Rochelle Walensky, director of the Centers for Disease Control and Prevention (CDC), has sent mixed messages about the likelihood that people vaccinated against COVID-19 will be infected by the delta variant of the coronavirus. While she has described so-called breakthrough infections as "rare" and this week reiterated the point that vaccinated people face a "far lower" infection risk than unvaccinated people, she also has offered an estimate implying the reverse: that vaccination somehow makes people more vulnerable to infection.
Walensky's statements about the likelihood that vaccinated carriers will transmit the virus likewise have been inconsistent, confusing, and sometimes stronger than the evidence supports. That evidence includes a new study that found viral loads in vaccinated and unvaccinated COVID-19 patients were initially similar but dropped faster in the vaccinated group.
"The breakthrough infections, as rare as they are, have the potential to forward transmit with the same capacity as an unvaccinated person," Walensky told reporters on July 27, the day the CDC issued new guidance recommending that vaccinated people resume wearing face masks in public places if they live in "areas of substantial or high transmission." That statement contradicted a "science brief" that the CDC published the same day.