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 percent of the roughly 4.2 million people immunized.
About 92 percent of the infections in vaccinated residents did not require hospitalizations, while 303 people, or 6.8 percent, were hospitalized, according to 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 percent of the 4,450 confirmed breakthrough cases and 0.0019 percent of the 4,195,844 people fully vaccinated as of July 10.
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.
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 percent.
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.