Los Angeles County health officials have declared a community-wide hepatitis A outbreak following an alarming tripling of cases since 2023 and the detection of elevated virus levels in wastewater surveillance. The outbreak, which has already claimed seven lives, is showing unusual patterns that have perplexed experts, as recent infections are increasingly occurring in individuals without the traditional risk factors of homelessness, drug use, or international travel.
The county has confirmed 165 hepatitis A cases since 2024, with 29 new cases in just the first three months of 2025, according to NPR.
Shifting Outbreak Demographics Baffle Experts
What particularly concerns public health officials is the changing profile of those affected. While hepatitis A outbreaks typically concentrate among specific populations with known risk factors, this outbreak shows signs of broader community transmission affecting people with no obvious exposure routes.
“When the outbreak started, we were mostly seeing it in people who had those risk factors,” explained Dr. Sharon Balter, Director of Communicable Disease Control and Prevention for the L.A. County Department of Public Health. “We’re seeing less of that and more of it in places where we’re not entirely sure where people got the virus.”…