Unvaccinated Massachusetts residents are five times more likely to become infected with COVID-19 than are fully vaccinated residents and they are 31 times more likely to get infected than fully vaccinated residents who have received a booster dose, the Department of Public Health said Monday in a review of breakthrough cases in the Bay State.
Of all the breakthrough cases, about 3 percent resulted in hospitalization or death while nearly 97 percent of all breakthrough infections did not require hospital care or result in death.
The agency said that 99.9 percent of breakthrough infections among fully vaccinated residents under the age of 60 did not result in death.
“The data are clear. This review shows that fully vaccinated people in Massachusetts have near-universal protection from severe illness and death and that boosters are demonstrating even stronger protection from COVID,” Health and Human Services Secretary Marylou Sudders said. “Amid the season of gathering indoors and the emerging Omicron variant, the time to get vaccinated and boosted is now. It is the best gift of protection for yourself and your loved ones.”
Since vaccination began last December, 88,968 vaccinated Massachusetts residents have been infected with COVID — roughly 2 percent of the state’s vaccinated population, DPH said.
About 2,224 of those people (2.5 percent) were hospitalized after their breakthrough infection was detected and did not die.
Roughly 463 people (0.52 percent) who had a breakthrough infection were hospitalized and died, and about 178 of the people (0.2 percent) who had breakthrough infections died within 60 days of their case being identified but never were hospitalized, DPH said.
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