By Kristina Rex

BOSTON (CBS) – “It’s surprising you know?” Tufts Medical Center epidemiologist Shira Doron said. “It’s not what we’ve been seeing.”

She was referencing an outbreak of COVID-19 among fully vaccinated people following the Fourth of July holiday in Provincetown. Infection numbers among fully vaccinated individuals are in the two dozens, and growing.

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“The delta variant is very contagious,” Dr. Doron explained. “We don’t know whether or not this is due to the delta variant yet but statistically the chances are that it is.”

In Massachusetts, there have been breakthrough COVID-19 cases in roughly 0.1% of the vaccinated population. In Provincetown, entire homes of visitors over the Fourth have tested positive, despite being fully vaccinated.

“I would never advise people to panic, but I think this is something we should look at. I don’t want to sweep it under the rug. I think this is going to be something that we learn from,” Dr. Doron said.

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While our existing vaccines do prevent the majority of COVID-19 infections, there is always the possibility of being infected. Still, the vaccine will likely prevent severe infection, hospitalization, and death, experts say. So far in the Provincetown cluster, most infected people have reported mild symptoms.

“It has always been a risk that a vaccinated person in a crowded situation, especially with a highly transmissible variant circulating, could get infected,” said Dr. Doron. “So if you are risk-averse and you really do not want to get COVID-19, don’t even want to get a mild case of COVID-19, you really don’t want to take that tiny really tiny risk… Then you shouldn’t be going to crowded places without a mask,” she explained.

Doron says she will be keeping a close eye on the Provincetown cluster and looking for more information to come out as more people continue to get tested. Still, she and others say getting vaccinated against COVID-19 is our best existing method of protection. “By getting vaccinated, you have fulfilled your biggest public health responsibility and you are allowed to go to crowded bars and nightclubs without a mask,” she said. “It’s now a personal choice.”

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Provincetown will be offering free COVID-19 testing from Wednesday through Monday at the Veterans Memorial Community Center on Mayflower Street.

Kristina Rex