Hepatitis A Outbreak Prompts Public Health Alert in Los Angeles County

Los Angeles County has declared a widespread outbreak of hepatitis A, a highly contagious viral infection that can cause serious liver complications or even death if not properly addressed. The outbreak has raised alarms among health officials, especially as the number of cases has surged significantly compared to previous years.

While hepatitis A has been present in the region before, recent data shows a troubling increase in infections, with 165 cases recorded in 2024—triple the number from the previous year—and representing the highest count in over a decade. Seven fatalities have been linked to the ongoing outbreak, which has now persisted for over a year.

Historically, hepatitis A cases in L.A. County have predominantly impacted homeless populations due to limited access to sanitation facilities. However, this year, a majority of new infections have been reported among individuals who are neither homeless nor have travel or illicit drug use as risk factors, indicating broader community spread.

Health authorities emphasize the urgency of rapid intervention. Dr. Muntu Davis, the county health officer, underscored the importance of vaccination and other preventive measures to curb the outbreak. In the first quarter of 2025 alone, 29 cases have been reported, doubling the number from the same period last year.

Hepatitis A spreads through contact with contaminated food, water, or objects, and via close contact with infected individuals. The virus can be present in stool and blood and infect others through ingestion of contaminated substances, or through certain behaviors such as drug use and sexual contact.

The true scale of the outbreak may be underestimated because many infections are asymptomatic or go undiagnosed. Still, this outbreak surpasses the 2017 incident, which had 87 confirmed cases. Experts warn that wastewater surveillance signals suggest the outbreak could be more extensive than confirmed cases alone.

Symptoms typically include fever, fatigue, stomach pain, nausea, jaundice, and dark urine. Notably, adults often experience pronounced symptoms, with over 70% developing jaundice, whereas children under six are often asymptomatic.

While most recover fully, hepatitis A can cause severe liver damage or fatality. Genetic analysis indicates that the strain involved is predominantly found in L.A. County and some neighboring regions.

Vaccination is the most effective prevention. The CDC recommends two doses of hepatitis A vaccine starting at age one or two, with the second dose administered at least six months later. The vaccine is highly effective and widely available at healthcare providers and pharmacies.

Given the outbreak, health officials strongly advise unvaccinated residents—especially those experiencing homelessness or using drugs—to get vaccinated. Even those unsure of their vaccination status should do so, as the vaccine is safe and beneficial.

Preventive hygiene practices are also critical, including frequent hand washing with soap and water and using hand sanitizers with at least 60% alcohol.

The incubation period ranges from 15 to 50 days, with symptoms lasting from a week to several months in severe cases. Due to the lengthy incubation, early detection and vaccination are crucial.

The resurgence of hepatitis A in L.A. County raises concerns about the decline in federal funding for surveillance, vaccination programs, and outbreak response efforts. Cuts to grants could hinder detection and control efforts, emphasizing the need for continued public health investment.

Health officials urge the community to remain vigilant, get vaccinated, and practice good hygiene to prevent further spread. Efforts to control the outbreak are ongoing, but sustained support and funding are essential to protect public health.

source: https://medicalxpress.com/news/2025-05-hepatitis-outbreak-declared-la-county.html