Measles Cases Surge in US, UK, Australia on Low Vaccination

Measles cases continue to surge across multiple countries, threatening hard-won elimination efforts and highlighting vulnerabilities from declining vaccination rates. In the United States, the United Kingdom, and Australia, health authorities have reported hundreds of infections this year, primarily among unvaccinated individuals, with outbreaks linked to both international travel and local transmission.

The United States is experiencing its most severe measles activity in decades, with 1,362 confirmed cases reported in 31 states as of early March 2026, surpassing more than half of the 2,284 cases recorded for all of 2025, the highest annual total in 33 years. Major outbreaks persist in Arizona, with 56 cases this year and 276 overall since last year; Utah, with 209 cases this year and 405 total; and South Carolina, reporting 664 cases this year amid 993 total. Additional hotspots include Florida, with 132 cases, many tied to a February university outbreak; Texas, with 93 cases, including 14 among detainees at an immigration facility in El Paso; and California, with 29 cases across three outbreaks, one involving a toddler who traveled from South Carolina. The Centers for...