BOSTON (WHDH) - New data from the Department of Public Health shows that 73 percent of COVID-19 breakthrough deaths in Massachusetts have been among vaccinated residents with at least one underlying condition and their average age was 82.5.

As of July 31, there have been 100 reported breakthrough case deaths (0.002 percent of all fully vaccinated individuals).

Health officials said that the underlying conditions made people “more likely to have severe disease.”

There have also been 395 breakthrough hospitalizations (0.009% of all fully vaccinated individuals) since the COVID-19 shots started rolling out. Fifty-seven percent of the breakthrough hospitalizations were reported to have underlying conditions

“Some of those COVID hospitalizations and COVID deaths are not hospitalizations due to COVID or deaths due to COVID,” said Tufts Infectious Disease Specialist Dr. Shira Doron. “Some of those are the fact that we test everybody on admission and we find some unexpected positives.”

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Massachusetts’ 74 percent vaccination rate among people over the age of 18 has been critical in keeping hospitalization numbers low, despite the recent uptick in case counts, officials added.

The number of fully vaccinated people across the state currently sits at 4,370,288, public health data shows.

While the highly contagious coronavirus Delta variant has been linked to a surge in new cases, Doron says fully vaccinated people should not get overly anxious because it’s not clear if the variant is more deadly than others.

Doron says that wearing a mask more often and avoiding large crowds might be a smart move.

“Think about your own personal risk and the risk of people you interact with,” Doron explained. “Assess the situation. Don’t put the vaccine to a stress test. No need to go into massively crowded bars and nightclubs with people screaming, especially if you have some underlying vulnerability.

In wake of the uptick in new COVID cases, Cisco Brewers and the Chicken Box on Nantucket announced that they will begin requiring proof of vaccination or a negative COVID-19 test to gain entry.

Bay State health officials on Monday reported 2,587 new COVID-19 cases, three additional deaths, and a seven-day positivity rate of 2.72 percent.

Six counties in Massachusetts are now considered high risk for COVID-19 transmission, while seven others are at substantial risk, according to the Centers for Disease Control and Prevention.

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