6:11 p.m. ET, August 2, 2021
Breakthrough infections in Provincetown represented a small share of those possibly exposed, CDC director says
From CNN’s Maggie Fox
Foot traffic along Commercial street in Provincetown, Massachusetts on Tuesday, July 20.
Barry Chin/The Boston Globe/Getty Images
Breakthrough infections recorded during an outbreak of virus in the popular Cade Cod town of Provincetown represented a small percentage of people exposed to the virus, US Centers for Disease Control and Prevention Director Dr. Rochelle Walensky said Monday.
“Last week we published data on an outbreak in Barnstable County Massachusetts, where there were 346 confirmed cases of Covid-19 in people who were fully vaccinated,” Walensky told a White House Covid-19 Response briefing.
“During the summer, some towns in Barnstable county can have up to 240,000 visitors per month,” Walensky noted.
“Those with breakthrough infections had viral loads that were similar to people who were infected and unvaccinated. This new finding, combined with data from other outbreak investigations and surveillance studies across the country, was critical in our decision to update our guidance for those who are fully vaccinated,” she added.
“Since those data were released, several other studies have been released over just this past weekend that have corroborated these findings. Taken together, the Delta variant is different from prior strains. I understand this is all frustrating news and I share this frustration.”
Walensky did not detail which other studies released over the weekend she was referring to. But she said these details help make clear the Delta variant of coronavirus is different and more transmissible.
“First, the Delta variant is highly contagious. To put this in perspective, if you get sick with the Alpha variant, you could infect about two other unvaccinated people. If you get sick with the Delta variant, we estimate that you could infect about five other unvaccinated people — more than twice as many as the original strain,” Walensky said.
“Second, infections with a Delta variant resulted in higher viral load. This means that those who are infected have a larger burden of virus that they can spread to others. Third, those higher viral loads are seen not just in those who are unvaccinated and infected, but also, and importantly, in the small proportion of those who are vaccinated and become infected.”