US measles cases reach 4,410 in 2026, nearly double last year's total

As of October 15, 2026, confirmed U.S. measles cases reached 4,410—nearly double the 2025 total of 2,289 and marking the highest level in over three decades. Pennsylvania serves as the epicenter with over 1,200 cases and six state-reported deaths, prompting the CDC to deploy Epidemic Intelligence Service officers. The resurgence coincides with declining kindergarten MMR vaccination rates, down to 92.4%, threatening the U.S. elimination status set in 2000.

Scale of the 2026 US measles outbreak

• ▪The 2026 U.S. measles outbreak reached its highest level in more than three decades, putting the nation's measles elimination status, established in 2000, at risk.
• ▪As of October 15, 2026, the CDC reported 4,410 confirmed measles cases across 45 states and Washington, D.C., an increase of 330 cases over the previous week.
• ▪The 2026 U.S. measles total of 4,410 cases represents a nearly 93% increase compared to the 2,289 confirmed cases recorded in all of 2025.

Age breakdown of U.S. measles cases

• ▪Through October 15, 2026, U.S. measles cases comprised 1,856 (42%) among children/teenagers aged 5–19 (largest group), 1,787 (41%, up from 29% in 2025) among adults 20+, and 742 (17%) among children under 5.
• ▪As of October 15, 2026, the CDC recorded 2,598 measles cases among individuals under 20 years old, while the age of 25 cases remained unknown.

Measles hospitalization numbers and rates

• ▪In Pennsylvania, state health department data through mid-October 2026 showed between 225 and 238 measles-related hospitalizations.
• ▪U.S. measles hospitalization rates in 2026 varied by age, with children under 5 hospitalized at 15%, adults 20 and older at 14%, and individuals aged 5 to 19 at 5%.
• ▪The CDC recorded 451 total measles-related hospitalizations in the U.S. in 2026 as of October 15, 2026, representing approximately 10% of all confirmed cases.

Vaccination status and declining coverage

• ▪Across the U.S., 96% of confirmed 2026 measles cases occurred in individuals who were unvaccinated or whose vaccination status was unknown.
• ▪U.S. kindergarten MMR vaccination rates dropped from 95.2% in the 2019–2020 school year to 92.4% in the 2025–2026 school year, falling below the 95% herd immunity threshold.

Pennsylvania outbreak and state response

• ▪Pennsylvania health center staff administered over 5,900 MMR vaccine doses across 202 pop-up clinics between late April and October 2026 to combat the state's outbreak.
• ▪Pennsylvania health officials reported six measles-related deaths in 2026, while the CDC officially confirmed two nationwide after shifting to National Center for Health Statistics mortality tracking.
• ▪Pennsylvania became the epicenter of the 2026 U.S. measles outbreak, recording between 1,200 and 1,260 cases across 42 counties as of mid-October 2026.

CDC Epi-Aid assistance to states

• ▪Additional states, including Texas, South Carolina, Virginia, Kansas, New Mexico, and Wisconsin, also utilized the CDC's Epi-Aid emergency response program during 2026 outbreaks.
• ▪Pennsylvania's request for CDC Epi-Aid support followed a dispute between federal and state officials over the criteria for defining and counting measles-associated deaths.
• ▪The CDC agreed to deploy an Epidemic Intelligence Service officer to Pennsylvania under the Epi-Aid program following a formal assistance request from state officials.

Statements and positions of HHS Secretary Kennedy

• ▪HHS Secretary Robert F. Kennedy Jr. attributed the 2026 measles surge to disrupted childhood vaccination during the COVID-19 pandemic, citing 2020 private diary entries by Dr. Anthony Fauci.
• ▪HHS Secretary Robert F. Kennedy Jr. and CDC Director Dr. Erica Schwartz maintained public recommendations for the MMR vaccine as the most effective defense against measles.
• ▪HHS Secretary Robert F. Kennedy Jr. clashed with Pennsylvania Governor Josh Shapiro in August 2026, with Kennedy accusing Shapiro of fabricating measles deaths and Shapiro accusing Kennedy of downplaying the disease.

New York disaster emergency declaration

• ▪New York became the first U.S. state to declare a disaster emergency over the 2026 measles outbreak.
• ▪New York Governor Kathy Hochul declared a statewide disaster emergency on October 5, 2026, expanding authority for healthcare staff to administer vaccines as measles cases surpassed 100.