The Centers for Disease Control and Prevention reports 5,182 confirmed measles cases in the United States in 2026, with cases now reported in 47 jurisdictions and 18 more among international visitors. The figures, updated on November 6 and covering cases reported as of November 5, mark the first time since 1991 that the national total has passed 5,000, and the outbreak count keeps climbing.
Why it matters
The detail behind the total is what worries health officials. There have been 43 new outbreaks reported in 2026, and 96 percent of confirmed cases are outbreak associated, with 3,608 cases from outbreaks that started in 2026 and 1,385 from outbreaks that started in 2025. An outbreak, by the CDC definition, is three or more related cases, and the concentration of cases inside outbreaks says the virus is spreading where it finds unvaccinated people, not evenly across the country.
The geographic spread is almost national. The 47 jurisdictions reporting cases run from Alabama and Alaska to Wisconsin and Wyoming, and they include New York City and the District of Columbia alongside 45 states. State, local, tribal and territorial health departments lead the case and outbreak investigations, and states notify the CDC of cases they confirm, which means the federal count always lags the local picture by days.
What happens next
The timing matters because the reporting cycle is weekly. The CDC updates its measles page on Thursdays, using cases reported as of noon that day, and it counts only confirmed cases that jurisdictions have formally notified. Probable cases that states report publicly do not appear in the federal total, so the real number of infections is higher than 5,182, and the next update will show whether the outbreak count has grown again.
What happens next will be decided state by state, in vaccination clinics and in outbreak investigations. Measles spreads through the air and can linger in a room for hours after an infected person leaves, which is why a single case in a school or a clinic can become an outbreak within days. Health departments are urging anyone unsure of their vaccination status to check it now, before the next exposure, not after.
