Amtrak is warning passengers of potential measles exposure after health officials announced that an infected person traveled from Philadelphia to Baltimore-Washington International Airport on a crowded train from January 7 to January 8.
Maryland health officials have listed several locations as possible measles exposure sites related to the unidentified infected traveler, including Philadelphia International Airport, Terminal A East from 7:50 to 11pm on January 7, an Amtrak train from Philadelphia’s 30th Street Station to Washington, DC from 9 to 11:30pm on January 7, the Amtrak shuttle to BWI Airport from 10:45pm to 1:30am and the BWI long-term parking shuttle from 11 pm to 2 am January 8.
Health officials did not disclose if the infected person had a fever, rash or other symptoms at the time of travel, nor whether they were in the highly contagious phase of the illness. It was also not stated if the individual had been vaccinated against measles.
They advised unvaccinated people to contact a healthcare provider or local health department and monitor for early symptoms within 21 days. Watch for a fever above 101 degrees Fahrenheit, cough, runny nose and red, watery eyes.
Measles symptoms emerge 10 to 14 days after exposure, followed by a facial rash that spreads over one to four days. The person can transmit the virus from four days before the rash appears until four days after.
Measles is the world’s most contagious disease. An unvaccinated person has a 90 percent chance of infection if briefly sharing air with a contagious person, even hours later. Measles kills about three in every 1,000 infected people.
This potential exposure event occurs as the US faces a significant resurgence of measles. Last year saw 2,144 confirmed cases, the highest annual total since the disease was declared eliminated in 2000 and the most in over three decades.
Several states have emerged as viral hotspots for measles. In Utah, officials confirmed 20 new cases this week, raising the state’s 2025-2026 total to 176. Meanwhile, in the Southeast, North Carolina has reported five cases since late December, including one in 2026, and South Carolina has added 99 new infections, bringing its statewide total to 310.
A person infected with measles traveled on an Amtrak train from Philadelphia’s 30th Street Station [pictured] to BWI Airport in Maryland on January 7
Meg Sullivan, the Maryland Department of Health’s deputy secretary for Public Health Services, said: ‘Vaccination remains essential to protecting ourselves, our families, and our communities against measles and other infectious diseases.
‘These types of situations underscore the importance of knowing your vaccination status and ensuring you are up to date with all recommended vaccines.’
According to the CDC, 93 percent of measles cases are in unvaccinated people or those with an unknown vaccine status. Three percent have received one dose of the MMR vaccine and four percent have received both doses.
The odds of a vaccinated person becoming infected is very low, about three percent.
Even if infection occurs, symptoms are typically far milder and the risk of severe complications or transmission is drastically reduced.
According to national data, 11 percent, or 240 people infected, have been hospitalized and three people have died in the current outbreak.
Nearly 20 percent of children under five infected during the current outbreak have required hospitalization.
The US formally eliminated measles in 2000, meaning there had been no community spread in 12 months, thanks to widespread uptake of the measles, mumps and rubella (MMR) vaccine.
But the level of population-wide immunity needed to stave off outbreaks and protect vulnerable populations, about 95 percent, has sunk to less than 93 percent, suggesting the cases documented in 2026 are just the beginning.
Enclosed train cars and airports are extremely risky locations for disease transmission. The measles virus spreads via airborne droplets when an infected person coughs or sneezes.
Measles first invades the respiratory system, then spreads to the lymph nodes and throughout the body. As a result, the virus can affect the lungs, brain and central nervous system.
While measles sometimes causes milder symptoms, including diarrhea, sore throat and achiness, it leads to pneumonia in roughly six percent of otherwise healthy children, and more often in malnourished children.
While the brain swelling that measles can trigger is rare, occurring in about 1 in 1,000 cases, it is deadly in roughly 15 to 20 percent of those who develop it, while about 20 percent are left with permanent neurological damage such as brain damage, deafness or intellectual disability.
It also severely damages a child’s immune system, making them susceptible to other potentially devastating bacterial and viral infections they were previously protected against.
A significant measles outbreak that started last year in West Texas, primarily within a largely unvaccinated religious community, quickly spread across state lines to the rest of the country. Texas officials have recorded more than 760 cases since January 2025.
Before MMR vaccines became available in the 1960s, measles caused epidemics with up to 2.6 million global deaths every year. By 2023, that number had fallen to roughly 107,000 deaths.
The World Health Organization estimates that measles vaccination prevented 60 million deaths between 2000 and 2023.
Robert F Kennedy, Jr, in his capacity both as current head of the Department of Health and Human Services and as co-founder of the nonprofit Children’s Health Defense, has consistently cast doubt on the safety and efficacy of well-studied vaccines such as the MMR shots.
After the death of an eight-year-old girl in Texas, Kennedy acknowledged the MMR vaccine is the most effective way to prevent measles, while at the same time promoting vitamin A as an effective treatment, which is believed to have contributed to several small children being hospitalized with an overdose.
High-dose vitamin A is a standard, evidence-based treatment for measles, proven to reduce the risk of death and severe complications like pneumonia. Its life-saving effect is most pronounced in individuals with pre-existing vitamin A deficiency.
