The Maryland Department of Health declared a measles outbreak Thursday across St. Mary’s, Carroll and Cecil counties after confirming 14 new cases, all among unvaccinated residents, bringing the state’s 2026 total to 31 confirmed cases. Health officials say no public exposure sites have been identified in connection with the new cases, and most infections have occurred among household contacts rather than spreading more broadly.
The 31 cases mark a sharp escalation from earlier in the year. Maryland recorded just one measles case in both 2023 and 2024, and three in all of 2025. This year’s total was still in the single digits through mid-July — nine cases as of July 16, driven largely by residents who had traveled to active outbreak areas out of state. That changed quickly: 27 of the state’s 31 cases this year have been confirmed since July 15 alone, all in unvaccinated residents, split among St. Mary’s (13), Carroll (8), Cecil (5) and Charles (1) counties. The four earlier 2026 cases were in Anne Arundel, Baltimore and Prince George’s counties.
“Measles is highly contagious and we are actively working with healthcare professionals and local health departments to support impacted communities, respond to cases and mitigate further spread,” said Maryland Health Secretary Dr. Meena Seshamani. “The overall risk remains low if you are fully vaccinated.”
State health officials have consistently pointed to Maryland’s relatively high vaccination rate as the reason the state hasn’t seen sustained, wider community transmission despite the rising case count. Roughly 96% of Marylanders have vaccine-based protection against measles, and 96.7% of kindergartners were reported vaccinated for the 2025-2026 school year, according to the department. An unvaccinated person exposed to measles has about a 90% chance of becoming infected, the department said.
The outbreak also fits a larger national pattern. More than 2,300 measles cases had been confirmed across 44 states and Washington, D.C., as of early August, with Virginia and Pennsylvania — both bordering Maryland — experiencing significant outbreaks of their own, raising the odds of exposure for Marylanders who travel there.
The MMR vaccine is recommended at 12-15 months for a first dose and 4-6 years for a second, per the American Academy of Pediatrics; infants 6-11 months old in or traveling to an outbreak area should be considered for an early dose. Adults are recommended to have at least one documented MMR dose, with two doses recommended for those at higher risk. Residents can check their vaccination status through their health care provider or by requesting records through the state’s My Immunization Record system online.
More than 106,000 MMR vaccines have been administered in Maryland so far in 2026, including more than 24,000 since July 1, according to the health department. Standard health insurance typically covers the vaccine, and it’s available at no cost for uninsured or underinsured children through the Vaccines for Children Program, or for adults through the Maryland Vaccine Program via local health departments.
The health department said it will not release additional details about the individual patients involved, citing privacy protections. St. Mary’s County has been the site of earlier measles activity this year: two cases tied to out-of-state travel were confirmed there in July, with several public exposure sites identified at the time, including a feed store and two medical facilities in the Mechanicsville and Charlotte Hall area.
