US reports 4,410 measles cases in 2026; Pennsylvania emerges as latest hotspot: CDC report

The United States has reported 4,410 measles cases as of October 15, up 330 from the previous week, as the highly contagious disease continues to spread, according to the Centers for Disease Control and Prevention (CDC).Pennsylvania has emerged as a major hotspot, with state health department data showing 1,260 cases and 238 related hospitalisations as of October 16. The state has reported six measles-related deaths, according to ABC News, while the CDC has confirmed two measles-associated deaths nationwide in 2026 without identifying the states involved.The CDC said it would provide additional assistance to Pennsylvania to investigate the outbreak and strengthen local response efforts. The agency's move follows a formal request from the state for support through its Epidemic Intelligence Service's Epi-Aid programme, ABC News reported, citing a CDC spokesperson."Pennsylvania has formally requested CDC assistance through the Epi-Aid program. In response, CDC will support the state's identified needs and strengthen its response efforts on the ground," a CDC spokesperson told ABC News in a statement.Children and teenagers aged 5 to 19 accounted for the largest share of cases nationwide, with 1,856 infections, or 42 per cent of the total, CDC data showed. Adults aged 20 and older accounted for another 1,787 cases, or 41 per cent.About 96 per cent of cases were among people who were unvaccinated or whose vaccination status was unknown, according to CDC data cited by ABC News. The agency recommends two doses of the measles, mumps and rubella (MMR) vaccine to protect against infection.The outbreak comes amid concerns over declining childhood vaccination rates. CDC data showed that 92.4% of US kindergartners received the MMR vaccine during the 2025-26 school year, down from 95.2% in 2019-20.Last month, the CDC changed its approach to tracking measles-related deaths, shifting to mortality data from the National Center for Health Statistics rather than relying on state health departments, a move that has drawn scrutiny.Earlier this month, New York declared a disaster emergency over its measles outbreak, marking the first such declaration by a US state, according to Reuters.You use AI every day. Now get your AI Quotient. Take the AIQ test.