By Louisa Moller

PROVINCETOWN (CBS) – At indoor bars, restaurants, dance floors, and performance venues, masks are now required in Provincetown, even as the town manager says the COVID-19 case count is plateauing.

“We think that with a mask mandate we will see the test positivity rate go down at a faster rate,” said Provincetown Town Manager Alex Morse.

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Morse says it’s an emergency measure to extinguish a COVID outbreak that started July 1 and now stands at 551 cases, roughly three quarters of which occurred in fully vaccinated people.

That includes 53 samples which the Department of Public Health says tested positive for the highly contagious delta variant.

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“We peaked at about 15% positivity rate of our daily tests on July 15,” Morse said. “Yesterday’s testing showed us we are down to 7%

The town’s plan is to remove the mask mandate once the positivity rate dips below 3%. A good move for now says Tufts Medical Center epidemiologist Dr. Shira Doron. “I don’t think it’s wrong, because this is a growing public health threat to try to use all the tools in the toolbelt,” Doron said.

But she notes that vaccines are more effective and may have protected the third of the cluster that is not vaccinated. “Masks certainly don’t work as well as vaccination,” Doron said.

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Among the cluster, the town manager says there have been three hospitalizations and the only person who remains in the hospital is unvaccinated.

Louisa Moller