A baby getting a medical exam. Measles vaccinations can be given as early as 6 months, doctors say. (Photo by Ariel Skelley/Getty stock photo)
Health officials have confirmed three measles cases in Maryland this month, but say it’s not time to panic about an outbreak given the state’s more than 96% vaccination rate against the highly transmissible virus.
But with outbreaks occurring in other states, experts are urging Marylanders to make sure that they are up to date with their vaccinations, to protect vulnerable populations and ensure that measles stays manageable in the state.
“What we’re seeing now with three imported cases, that doesn’t concern me. It’s a reflection of what’s happening globally and people traveling,” said Dr. William Moss, a professor of epidemiology at the Johns Hopkins Bloomberg School of Public Health.
“What would concern me is if we started seeing more locally acquired cases where people who did not travel acquired measles in Maryland,” Moss said.
The Maryland Department of Health announced on March 9 that a Howard County resident who had traveled internationally had contracted measles.
Two other international travelers, this time from Prince George’s County, also caught measles while abroad, the health department reported Thursday.
While all three cases were connected to Washington Dulles International Airport, the Prince George’s cases are not related to the Howard County case, according to the health department. And the department said none of the Maryland cases are related to ongoing outbreaks identified in New Mexico, Texas, and Oklahoma, some of which have led to fatalities.
But out of “an abundance of caution,” the agency issued a list of potentially exposed flights, Metro lines and hospitals where the public might have been exposed to one of the Maryland cases.
“Measles cases occur sporadically in Maryland, with one case of measles identified in Maryland earlier this year [the March 9 case], one in 2024, one in 2023, and no cases from 2020-2022,” the department said in a statement Thursday.
With three cases identified in March alone, should Marylanders expect an outbreak? Public health experts say no — so long as you’re vaccinated, which more than 96% of the state’s residents are, according to Dr. Georges Benjamin, executive director for the American Public Health Association.
If people who’ve contracted measles virus “happen to go into a community that is unvaccinated or undervaccinated, or around a child under the age of 1 that has not yet had their vaccine, you can see spread,” he said. “But the likelihood of a big outbreak occurring in Maryland is relatively low. Very low.”
Measles starts as a standard respiratory disease, with a fever, runny nose, cough and red, watery eyes. A couple days after the initial symptoms, people sick with measles may develop the illness’s calling card – a red, bumpy rash that starts on the head area and spreads to the rest of the body.
Moss said that while the measles virus travels more quickly among unvaccinated populations, breakthrough cases among vaccinated people are still possible, though rare. He advised that those who suspect they may have been exposed to measles shouldn’t just walk into an emergency room if they can avoid it, due to how transmissible it is.
“Because measles virus is so contagious, you don’t want someone with measles just walking into a crowded emergency room with a lot of other sick people,” Moss said.
“Ideally what would happen is that a parent or an individual would contact their health care provider to give them a heads up that … they think they could have measles,” he said. “That way … they can be prepared to handle that patient and make sure that patient doesn’t pass the infection to others.”
People can get vaccinated for measles as early as 6 months old, and Maryland schools require kindergartners to be vaccinated for measles and other diseases before entering class, although the state has a liberal religious exemption policy.
More parents using religious exemption to opt children out of school vaccinations
But Moss is concerned about a rising national trend of parents asking for religious exemptions from required vaccinations to attend state schools – a trend that Maryland is not immune to.
Since the COVID-19 pandemic, more parents have invoked a religious exemption to opt their children out of vaccination requirements in recent years, which Moss and other public health experts say is an indication of increased vaccine hesitancy.
In the 2023-24 school year, for example, 1.54% of Maryland kindergartners received a religious exemption from required vaccinations, including the MMR vaccine which helps protect against measles, mumps and rubella. Religious exemptions have been growing steadily since 2002-2003, when only 0.2% of students were exempted, state data shows.
According to health department data, of those 98.46% of kindergartners who were vaccinated last school year, 99% received the MMR vaccine. Vaccine rates for the current academic year are not yet available.
“Successful vaccination programs undermine themselves because the disease goes away and people don’t worry about these vaccine-preventable diseases that can actually come back,” Moss said. He added that vaccine hesitancy has grown since the COVID-19 pandemic.
“I would hope for many people the current measles outbreak here in the United States is a reminder that measles is still around, that measures can still put people in the hospital, that measles can still kill,” he said. “And that will highlight the value of measles vaccination and that we’ll be able to maintain high measles vaccination coverage here in Maryland and nationally.”
He said that if Maryland can maintain high vaccination levels, it can keep a potential future outbreak at bay.
“My prediction would be that we’re not going to see many secondary cases as a consequence of these importations in Maryland,” Moss said. “I think we’re pretty good here.”