California Records Highest Measles Cases in Seven Years Amid National Resurgence
California has reported its highest number of annual measles cases in seven years, with at least 40 confirmed infections in 2026, surpassing the total for all of 2025. Health officials attribute this surge to declining vaccination rates, which have fallen below herd immunity thresholds in certain communities. Data indicates that 95% of recent cases involved unvaccinated individuals or those with unknown immunization status, predominantly affecting people under age 20. This local trend mirrors a nationwide resurgence, with over 1,700 confirmed cases across the United States this year, approaching the record highs seen in 2025. The measles-mumps-rubella (MMR) vaccine remains highly effective, yet pockets of vulnerability are allowing outbreaks to spread. Recent incidents include an infant in San Francisco contracting the virus during international travel and a tragic death in Los Angeles County linked to measles complications. Experts warn that the U.S. risks losing its elimination status for the disease, previously declared achieved in 2000, as preventable outbreaks become more frequent and severe.
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California Records Highest Measles Cases in Seven Years Amid National Resurgence
California has reported its highest number of annual measles cases in seven years, with at least 40 confirmed infections in 2026, surpassing the total for all of 2025. Health officials attribute this surge to declining vaccination rates, which have fallen below herd immunity thresholds in certain communities. Data indicates that 95% of recent cases involved unvaccinated individuals or those with unknown immunization status, predominantly affecting people under age 20. This local trend mirrors a nationwide resurgence, with over 1,700 confirmed cases across the United States this year, approaching the record highs seen in 2025. The measles-mumps-rubella (MMR) vaccine remains highly effective, yet pockets of vulnerability are allowing outbreaks to spread. Recent incidents include an infant in San Francisco contracting the virus during international travel and a tragic death in Los Angeles County linked to measles complications. Experts warn that the U.S. risks losing its elimination status for the disease, previously declared achieved in 2000, as preventable outbreaks become more frequent and severe.
latimes