Measles and Infectious Disease Outbreaks

DC Health warned that multiple confirmed measles cases were contagious while attending the Jan. 21 National March for Life and using D.C. transit and venues — including Reagan National Airport, Union Station, an Amtrak Northeast Regional train, the D.C. Metro, the Basilica of the National Shrine, Catholic University and Children’s National Hospital — and urged anyone potentially exposed to watch for symptoms and seek vaccination or medical care. The alert comes amid a nationwide resurgence: U.S. measles topped more than 2,000 confirmed cases in 2025 (the highest since 1991) with hundreds more in 2026, driven by large outbreaks in South Carolina and West Texas, falling MMR coverage (roughly 92–93% vs. the 95% herd‑immunity threshold), and recent federal changes to childhood vaccine guidance that experts say have contributed to declining uptake and put the country’s measles‑elimination status at risk.