(NEXSTAR/WTEN) – A passenger on an Amtrak train to Washington, DC, last week may have exposed numerous people to the measles, according to a notice from the DC Department of Health. Officials with DC Health said the passenger had boarded a southbound Amtrak Northeast Regional, which originated in Boston, on March 19. This person also may have exposed other travelers at the Amtrak concourse in DC’s Union Station upon arrival, according to the notice. ‘Like a forest fire’: Where large measles outbreaks will occur, according to an epidemiologist A few days later on March 22, this person also visited an urgent care center — MedStar Urgent Care Adams Morgan — in DC. “DC Health was notified of a confirmed case of measles in a person who visited multiple locations in DC while contagious,” reads the notice. “DC Health is informing people who were at these locations that they may have been exposed.” Officials with the Minnesota Department of Health have since identified this passenger a resident of the state’s Hennepin County. They also said this person had recently traveled both domestically and internationally. “The person was not infectious while in Minnesota, so there were no exposures in Minnesota from this case,” reads a statement provided by Jayne Griffith, an epidemiologist with Minnesota’s Department of Health. An Amtrak train is pictured at Union Station in Washington, DC, on November 28, 2023. (Bastien Inzaurralde/AFP via Getty Images) A representative for DC Health also confirmed to Nexstar that this person was vaccinated, suggesting the passenger had experienced a breakthrough infection. (Breakthrough infections are “uncommon” but can still occur, the Centers for Disease Control and Prevention acknowledges.) Those who believe they may have been exposed to measles are urged to monitor for symptoms and contact a healthcare provider with any concerns. Kansas measles cases double to 23 and new Ohio outbreak sickens 10 News of the passenger potentially exposing other travelers and DC residents to the measles comes amid reports of measles outbreaks across the country. Epidemiologists with the Centers for Disease Control and Prevention (CDC) have confirmed nearly 400 cases across 18 states, with the largest outbreaks reported in Texas and New Mexico. In 2024, the CDC recorded under 300 cases, nationally, for the whole calendar year. Health officials say the best way to protect from measles infection is two doses of the MMR (measles, mumps and rubella) vaccine. ...read more read less