Need for Continued Vigilance for Hepatitis A Infection and Vaccination for High Risk Groups April 25, 2018 Public Health 1022 Key Messages There have been no new cases of hepatitis A (HAV) infection in Los Angeles County in 2018 among outbreak-associated populations (persons who are homeless or using illicit drugs) nor among men who have sex with men (MSM). There are multiple ongoing HAV outbreaks in California among persons experiencing homelessness and/or using illicit drugs and as well as national and international outbreaks among MSM. In light of these other outbreaks, LAC DPH is asking providers to remain vigilant for HAV infection and to promote hepatitis A vaccine to high-risk groups, specifically: persons who are homeless or using an illicit drug, persons who have frequent close contact with the homeless or drug-using populations, and to MSM. The 2017 hepatitis A vaccine supply constraints have resolved. Providers may now use either single-antigen HAV or the combined HAV/HBV vaccine. Background LAC DPH declared an outbreak of HAV among persons who are homeless or using illicit (injection and non-injection) drugs in September 2017 and reported an increase in HAV cases among men who have sex with men (MSM) in November 2017. Current Situation To date in 2018, no HAV cases have been reported among persons who are homeless or using illicit drugs in LA County. This compares with 16 HAV cases from July to October 2017 and then 1 HAV case from November 2017 to December 2017. Among MSM, there have been no cases in 2018 compared with a total of 20 cases in 2017. LAC DPH is asking providers to remain vigilant for HAV for two reasons. First, there are multiple ongoing HAV outbreaks in California, including in San Diego County, so the potential exists for the introduction of new HAV cases into LA County. Second, persons who are homeless or using illicit drugs and MSM are at high risk for acquiring HAV and many are not immune to HAV. Introduction of HAV into these populations could lead to a widespread increase of cases. Hepatitis A vaccine shortage has resolved In 2017, due to hepatitis A vaccine supply constraints, LAC DPH recommended prioritizing the single antigen vaccine for persons who were a part of the outbreak population and persons with close frequent contact with the homeless or drug using populations. The California Department of Public Health has informed LAC DPH that the supply of hepatitis A vaccine available through the Centers for Disease Control and Prevention (CDC) to public health agencies is no longer constrained. The vaccine supply available to the private market has also increased and supply constraints are expected to fully resolve by summer 2018. LAC DPH no longer recommends prioritizing one vaccine over another nor routine prescreening for immunity. Providers may now use either single-antigen HAV or the combined HAV/HBV vaccine per CDC recommendations. Below is a summary of current and updated LAC DPH hepatitis A outbreak prevention and control recommendations. Providers are also encouraged to review the November Rx for Prevention article, Clinical Recognition, and Management of Hepatitis A in the Context of an Ongoing Outbreak in Los Angeles County for more detailed information about HAV diagnosis, management, and control. Actions Requested of Providers: Promptly report all suspect and confirmed HAV cases to LAC DPH within 24 hours by calling 888-397-3993. After hours, call 213-974-1234. This will facilitate immediate interview by a public health investigator and timely provision of prophylaxis to contacts. Do not discharge patients with confirmed HAV to the street or communal shelter until at least a week after the onset of jaundice. Health Officer Orders are available to facilitate holding patients for discharge planning. For assistance call: 888-397-3993 during business hours and 213-974-1234 after hours. Follow standard environmental sanitation protocols to prevent the spread infectious diseases, including HAV. Promote HAV vaccine to all persons at increased risk for acquiring HAV infection or for experiencing complications from HAV