PROVINCETOWN — The Massachusetts Department of Public Health on Friday evening confirmed Cape Cod officials’ suspicions that the highly contagious Delta variant is part of the reason for the outbreak of COVID-19 cases in Provincetown.
The news came just hours before Provincetown and Barnstable County officials announced Saturday morning that the cluster involved 430 confirmed positive cases as of Friday — more than triple the 132 cases reported on Monday.
The cases overall include 342 Massachusetts residents, 153 of whom live in Provincetown, the announcement said. Of the Massachusetts residents affected, 69% reported they are fully vaccinated, and while two of three related hospitalizations are in-state, symptoms in the other cases “are known to be mild and without complication,” according to details from the Provincetown Select Board and Board of Health, and the county Department of Health and Environment.
Daily testing of Provincetown wastewater was due to begin immediately, officials said, and was used as a COVID-19 surveillance tool throughout the pandemic. The last wastewater sampling was done this spring.
The number of cases is expected to rise as more people take advantage of testing that had been made available. The presence of COVID-19 in the wastewater is expected, the officials said.
Access to expanded free testing and vaccinations in town has been extended through Friday, and those have proven “to be vital tools in the response effort as participation numbers increase daily,” officials said.
The Delta variant has been sweeping across the country, and the state DPH on Friday said the genetic sequencing of initial samples associated with the Provincetown cluster tested positive for the Delta variant.
Both the State Public Health Laboratory and the Broad Institute of MIT and Harvard identified the Delta variant in cases associated with this cluster, officials said, and additional specimens from the Provincetown cluster are continuing to be prioritized for sequencing.
No new variants have been identified, the DPH said.
COVID-19 vaccines remain key tool
While the DPH has identified cases in the cluster associated with vaccinated individuals, officials emphasized the total number of cases among vaccinated people in Massachusetts remains “extremely low” at 0.1% or 5,166 cases out of over 4.3 million fully vaccinated residents.
“All three COVID-19 vaccines in use in the U.S have shown to be very effective against the COVID variants and remain the single best way for people to protect themselves, their loved ones, and their community from COVID-19 and its variants,” the Friday announcement said. Even in “breakthrough” cases among vaccinated individuals, officials have also said the vaccines continue to offer enormous protection against severe symptoms from the disease.
Cape health and government officials watching the uptick in Provincetown numbers earlier this week said they suspected the Delta variant was part of the cause but were waiting for the DPH confirmation.
Timeline of ballooning COVID-19 cases
On Monday, 132 cases — most among vaccinated people — connected to Provincetown prompted town officials to issue a public health advisory, recommending that everyone wear masks indoors when social distancing isn’t possible, take other precautions and get tested.
All unvaccinated individuals — including children under 12 — are required to wear masks in public spaces indoors and in crowded places outdoors in the town, according to the advisory from Provincetown and Barnstable County.
More: Gov. Charlie Baker undeterred by surge in COVID-19 cases on Cape Cod
New COVID-19 cases not just in Provincetown
As of Thursday, Wellfleet, just two towns away from Provincetown, had five cases in town and one transient case, in both vaccinated and unvaccinated individuals, according to health and conservation agent Hillary Greenberg. Noting “much speculation about the Delta variant,” she issued a statement Friday urging residents to protect themselves and others based on the rising numbers.
She recommended businesses take precautionary steps: “At this time, I would like to request that masking be required in all public buildings and extend support to Wellfleet business establishments who choose to require the public to mask in efforts to better protect their staff and those vulnerable members of the public.”
The town has offered to supply masks to businesses if needed.
Nantucket this week also issued a mask advisory because of the rising number of COVID-19 cases on Cape Cod. Pointing to the increased virulence of the Delta variant, the town’s Health and Human Services Department “strongly recommended” masks and distancing, and that all residents and visitors, regardless of vaccination status, use masks while indoors and at public locations when physical distancing is not possible.
One of the COVID-19 deaths recorded over the past week in Barnstable County was a resident at a West Yarmouth nursing home hard-hit by a surge in the disease, Yarmouth Health Director Bruce G. Murphy said Friday.
More: Resident dies at West Yarmouth nursing home hit by COVID-19 surge
The resident contracted the disease during a recent outbreak at Maplewood at Mayflower Place, where nine employees and 24 residents have contracted COVID-19, most of them asymptomatic or mild cases, according to the DPH.
How the Delta variant differs
The Delta variant was first identified in India and is known to be more transmissible than the original COVID-19 virus, the DPH noted in its Friday announcement. Two factors, officials said, are that individuals infected with the Delta variant tend to have more virus in their respiratory tract than other variants and infected individuals may carry the virus longer.
The Centers for Disease Control and Prevention recently estimated that 83% of cases between July 4-17 are attributable to this variant nationally. The estimates during that same period for Region 1, which includes the New England states, are that Delta accounts for 68% of cases.
More: ‘Don’t come here’: Provincetown business owner calls for strict vaccination requirement
The rising numbers in Provincetown this week prompted many businesses to change policies, requiring that masks be worn inside or requiring proof of vaccination to enter entertainment venues.
Delta vs. the Alpha variant
Medical officials last week talked to the Times about the Delta variant being far more transmissible than the Alpha variant, also known as B.1.1.7, and about Delta supplanting Alpha as the dominant strain in Massachusetts.
Alpha, which was first detected in the United Kingdom, was 50% more transmissible than original or “wild” COVID-19. And Delta is 50% more transmissible than Alpha, said Dr. William Agel, chief medical officer for Cape Cod Healthcare.
Delta has a viral load that can measure 1,000 times higher than Alpha or wild COVID-19, which likely accounts for its greater transmissibility, said Dr. Donald Thea, a professor in the Department of Global Health at the Boston University School of Public Health.
“There seem to be more super spreaders” with the Delta variant, Thea said. “It is inevitable it will completely take over.”