CONCORD, NH (CBS/AP) – Schools in multiple New Hampshire communities were closed Monday because of teacher and staff absences attributed to COVID-19 vaccine side-effects.

Teachers, school staff and child care workers in New Hampshire became eligible for the vaccine last week, and vaccination clinics were held in numerous locations over the weekend.

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School was canceled Monday in Concord because of staff reactions to vaccines, Superintendent Kathleen A. Murphy said.

“The District just did not have enough substitutes or personnel to cover classrooms and common areas,” Murphy said. “I recognize the inconvenience that resulted, as you needed to find alternative care for your children and the loss of another day of instruction for students.”

Murphy said a Flex Day scheduled for Wednesday will be canceled to make up for the lost day. More Concord teachers will receive the vaccine next Sunday.

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A message on the Hillsboro-Deering district website described a similar situation.

“A large number of staff members received their COVID vaccines yesterday and many are reporting feeling very ill. There will be no remote or in-person learning for the high school today,” the message said.

The main side effects from the COVID-19 vaccines currently approved in the U.S. include pain at the injection site and flu-like fever, fatigue and headache.

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CBSBoston.com Staff