Map shows US measles cases as airport warning issued

Key Points:

• Measles cases in the U.S. have surpassed 3,400 in 2026, with Pennsylvania being the hardest hit state, reporting 745 cases compared to 16 in 2025, amid a national resurgence of the virus.
• Philadelphia health officials warned travelers who were at Philadelphia International Airport between the evening of September 13 and early September 14 to check their measles immunity and monitor for symptoms due to potential exposure.
• The CDC reports 39 new measles outbreaks this year, with 95% of cases linked to outbreaks, and notes that vaccination rates among U.S. kindergartners have declined, contributing to increased vulnerability.
• Measles is highly contagious, spreading through airborne droplets, and can cause serious complications, especially in young children, pregnant women, and immunocompromised individuals; vaccination remains the best protection.
• Despite some breakthrough infections, the MMR vaccine is highly effective, with two doses providing 97% protection, though public confidence in vaccines has decreased somewhat in recent years.