Measles case confirmed in DC, individual may have exposed others on Amtrak train
A measles case was confirmed in a person who traveled to Washington, D.C., on an Amtrak train, according to the D.C. Department of Health (DC Health).
The person visited multiple locations while contagious, including the southbound Amtrak Northeast Regional 175 Train and Union Station on March 19, as well as a MedStar Urgent Care in Adams Morgan on March 22, DC Health said in a press release on Tuesday.
DC Health said it is currently working to inform people who were at these locations that they may have been exposed.
Health officials are specifying that people who are "not immune" are most at-risk of infection. This includes those who are unvaccinated or who have never contracted measles before.
On Wednesday, health officials confirmed the measles patient is a Minnesota resident who recently traveled internationally. An investigation is ongoing to determine where the patient contracted measles.
The individual flew from Minnesota to Reagan National Airport but was not contagious at the time of their flight or while in Minnesota.
"On March 24, a case of measles was confirmed in an adult who lives in Hennepin County and had recently traveled domestically and internationally," Jayne Griffith, Minnesota Department of Health epidemiologist, said in a statement, "the person was not infectious while in Minnesota, so there were no exposures in Minnesota from this case. We are still investigating where this person acquired measles.
Health officials noted the individual was fully vaccinated with the measles, mumps, rubella (MMR) vaccine. Breakthrough infections are rare but possible. Fully vaccinated people who get measles are less likely to spread the disease to other people and typically have milder illness, the CDC said.
Amtrak released a statement indicating it was aware of an exposure on one of its trains.
"DC Public Health has notified Amtrak of a confirmed case of measles in a customer traveling on Amtrak Train 175 from New York to Washington Union Station on Wednesday, March 19," Amtrak said in a statement on Wednesday. "Amtrak is reaching out directly to customers who were on this train to notify them of possible exposure."
The New York City Department of Health and Mental Hygiene also released a statement on Wednesday, saying it is "aware" of the confirmed case and the patient's travel.
"Public Health agencies routinely exchange information when exposures occur in other localities, and we are in communication with the DC Department of Health on this matter," the statement read in part.
The CDC has confirmed 378 measles cases so far this year in at least 17 states: Alaska, California, Florida, Georgia, Kansas, Kentucky, Maryland, Michigan, New Jersey, New Mexico, New York, Ohio, Pennsylvania, Rhode Island, Texas, Vermont and Washington. This is likely an undercount due to delays in states reporting cases to the federal health agency.
Health officials are encouraging those who have never been vaccinated before to receive the MMR vaccine.
The CDC currently recommends that people receive two vaccine doses, the first at ages 12 to 15 months and the second between 4 and 6 years old. One dose is 93% effective, and two doses are 97% effective, the CDC says. Most vaccinated adults don't need a booster.
ABC News' Matt Foster and Othon Leyva contributed to this report.
