Two hundred and forty six Michigan residents have tested positive for Covid-19 after being fully vaccinated, three of whom have died.

Health officials in the state stressed that a small proportion of people take longer than two weeks to develop antibodies after their second shot. Those who caught Covid after both jabs also could have caught Covid prior to vaccination or in the gap between the two shots.

Lynn Sutfin, a spokeswoman for the Michigan Department of Health and Human Services, told The Detroit News that the cases were reported between 1 January and 31 March and that all of them had a positive test at least two weeks after getting their final vaccine dose.

She said: "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.

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 Michigan Department of Health had complete hospitalisation data for 117 of the cases, 129 were incomplete.

Ms Sutfin added: "Of the 117 with hospitalisation data entered, 11 were hospitalised, 103 were not hospitalised, and three are reported as unknown."
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