Nearly 80 people have died with COVID-19 in Massachusetts even though they were fully vaccinated as the more contagious Delta variant continues to spread.
These breakthrough cases where fully vaccinated individuals test positive for coronavirus have so far been rare, but are possible.
Here's what you need to know about breakthrough cases in Massachusetts:
How many breakthrough COVID cases are there in Massachusetts?
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Public health officials have tracked 4,450 "breakthrough" cases of COVID-19 among Massachusetts residents fully vaccinated against the disease, representing about one-tenth of 1% of the roughly 4.2 million people immunized.
About 92% of the infections in vaccinated residents did not require hospitalizations, while 303 people, or 6.8%, were hospitalized, according to state Department of Public Health data through July 10.
The Boston Herald reported the breakthrough data on Tuesday based on a public records request.
Seventy-nine vaccinated residents in Massachusetts died from COVID-19, either without being hospitalized or following a hospital stay, DPH said. That death toll reflects 1.78% of the 4,450 confirmed breakthrough cases and 0.0019% of the 4,195,844 people fully vaccinated as of July 10.
“All available data continue to support that all 3 vaccines used in the US are highly protective against severe disease and death from all known variants of COVID-19. The best way to protect yourself and your loved ones is to get vaccinated,” the DPH said in a statement to The Boston Globe.
Does this mean the vaccines aren't working?
Just the opposite. Health experts have said occasional infections after vaccinations are expected but that the immunizations greatly reduce the chances that contracting COVID-19 will lead to serious complications or death.
“Yes, the vaccines aren’t perfect. We expect that some folks will still be infected. But both in the studies and in real-life evidence they are awfully good,” Dr. Eric Rubin, an infectious disease physician at Brigham and Women's Hospital, told the Globe.
Since the pandemic began, DPH has confirmed 665,088 COVID-19 infections and 17,647 deaths -- the bulk of which occurred before most residents had access to vaccines -- for a fatality rate of nearly 2.7%.
The pace of new vaccinations has slowed considerably in recent weeks leading up to and after the June 15 end of the state of emergency. In the seven-day period ending May 30, the state averaged 41,918 vaccine doses administered per day, but that rate dropped to 10,880 for the seven-day period ending July 2.
Gov. Charlie Baker's administration has ramped up its focus on more targeted vaccine initiatives, supporting door-knocking campaigns, local outreach and incentive programs such as a state-run "VaxMillions" lottery open only to those who are fully dosed.
Breakthrough cases on the Cape?
Officials in Provincetown have sounded the alarm after a handful of new COVID-19 cases "overwhelmingly" affecting fully vaccinated individuals were reported in the Cape Cod tourist community in recent days.
Town Manager Alex Morse said Tuesday that, "Overwhelmingly, the affected individuals have been fully vaccinated for COVID-19. The moderate intensity of symptoms indicates that the vaccines are working as predicted."
He noted that the town, a popular tourist destination at the tip of Cape Cod, has among the highest vaccination rates in Massachusetts.
COVID testing is being stepped up in Provincetown, with free, walk-up mobile testing to be available at the Veterans Memorial Community Center parking lot through Monday.
According to the state, there have been 34 new coronavirus cases in Barnstable County in the past 14 days. Health officials said they are closely monitoring the situation.
What does the CDC say about breakthrough cases?
The Centers for Disease Control and Prevention said breakthrough COVID cases "are expected." They said no vaccines are 100% effective at preventing illness, but they are "a critical tool to bring the pandemic under control."
"More than 157 million people in the United States have been fully vaccinated as of July 6, 2021. Like with other vaccines, vaccine breakthrough cases will occur, even though the vaccines are working as expected," the agency said on its website.
The CDC said there is "some evidence" that vaccination may make the illness less severe for those who are vaccinated and still get the virus.
Current data suggests that the Moderna, Pfizer and Johnson & Johnson vaccines offer protection against most variants currently circulating in the U.S., the CDC said. But the variants will cause some breakthrough cases.