Overview
- Los Angeles County recorded 165 hepatitis A cases in 2024, tripling the previous year's total and marking the highest count in over 10 years.
- A community-wide outbreak was declared as cases continue to rise, with 29 confirmed in the first quarter of 2025—double the number from the same period last year.
- The outbreak is spreading beyond traditional high-risk groups, with over 15% of 2024 cases occurring among individuals without housing risk factors.
- Health officials are utilizing wastewater surveillance and genetic strain mapping to track the virus, which has also been detected in Orange and San Bernardino counties.
- Public health efforts include intensified vaccination campaigns, particularly targeting vulnerable populations, and reinforcing hygiene practices to curb transmission.