A child in Maine who recently tested positive for measles may be the state's first case of the viral infection since 2019, the Maine Department of Health and Human Services (DHHS) reported Friday (opens in new tab) (May 5).

While the case still needs to be confirmed by the federal Centers for Disease Control and Prevention (CDC), "out of an abundance of caution," Maine's public health agencies are assuming the child is infectious and working to identify and contact people who may have been exposed.

The CDC recommends (opens in new tab) that children receive their first dose of the MMR vaccine, which guards against measles, mumps and rubella, between 12 months and 15 months old. Children should get their second dose between 4 and 6 years old. Alternatively, the MMRV vaccine, which also guards against varicella (chickenpox), may be given following the same vaccination schedule.

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One dose of either vaccine is roughly 93% protective against measles, and two doses are 97% protective, meaning there's a small chance of infection even after two doses. However, vaccinated individuals tend to have much milder cases of the disease than unvaccinated people do.

The Maine child with a positive measles test had received one dose of a measles vaccine. (Neither the child's age nor any of their symptoms, if they had any, were noted in the DHHS statement.)

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The Maine DHHS statement includes a list of locations that the measles-positive child recently visited and times they were at each place. "Anyone at these locations during these times should watch for symptoms for 21 days after their exposure," the statement reads. "If you have symptoms, call a health care provider for instructions before going to the office or hospital to help prevent further spread of infection."

Between Jan. 1 and April 28, 2023, a total of 10 measles cases were reported nationwide, the CDC reported (opens in new tab).