Apr. 6—As many as 246 Michigan residents considered fully vaccinated against COVID-19 were later diagnosed with the virus, and three have died, state officials confirmed Monday.
The cases were reported between Jan. 1 and March 31, and the 246 had a positive test 14 or more days after the last dose in the vaccine series, said Lynn Sutfin, a spokeswoman for the Michigan Department of Health and Human Services, in an email.
"Some of these individuals may ultimately be excluded from this list due to continuing to test positive from a recent infection prior to being fully vaccinated," she said.
"These cases are undergoing further review to determine if they meet other CDC criteria for determination of potential breakthrough, including the absence of a positive antigen or PCR test less than 45 days prior to the post-vaccination positive test. In general, these persons have been more likely to be asymptomatic or mildly symptomatic compared with vaccinated persons."
The department had hospitalization data for 117 of the cases, but 129 were incomplete, she said.
"Of the 117 with hospitalization data entered, 11 were hospitalized, 103 were not hospitalized, and 3 are reported as unknown," Sutfin said.
The three deaths were "all persons 65 years or older, and two of which were within three weeks of completion of vaccination," she said. "While the majority of the population develops full immunity within 14 days of completion of their vaccine series, a small proportion appear to take longer to mount a full antibody response. CDC is actively working to better understand the risk characteristics of this group."
The figures come as Michigan COVID-19 cases continue to rise, and officials work to boost vaccinations.
On Monday, the state surpassed 700,000 cases and still leads the nation in new cases by population.
Hospitalizations for confirmed cases of COVID-19 are increasing at a faster rate than before Gov. Gretchen Whitmer shuttered indoor dining and suspended in-person high school classes in the fall.
Last week, Whitmer said she was increasing the state's goal from 50,000 shots administered per day to 100,000 shots per day.
As of April 4, about 2.95 million residents, or about 36.5% of Michigan's population, have been vaccinated, either with one or two doses, according to the state website. About 4.7 million doses had been administered.