In 2017, communities across the US (Southern California, Michigan, and New York City) are experiencing ongoing outbreaks and increases in acute hepatitis A virus (HAV) infections with cases occurring among unvaccinated persons at high risk for infection (homeless persons, IV drug users, men who have sex with men (MSM)). The Philadelphia Department of Public Health (PDPH) is reminding providers to routinely offer HAV vaccine to high risk patients and to promptly report any patient diagnosed with acute HAV by calling 215-685-6740 during regular business hours or 215-686-4514 after hours.
Acute HAV Disease Characteristics: In the United States, HAV is primarily spread person-to-person via the fecal-oral route and more rarely through contaminated food, water, or objects including injection drug paraphernalia. Typically, HAV infections are due to close personal or sexual contact with an infected person. Symptoms of acute HAV infection appear within 2 to 6 weeks of exposure and include discrete onset of abdominal pain, fatigue, dark urine, clay-colored stool, nausea, and vomiting along with jaundice/icterus or elevated serum aminotransferase levels. Children over 6 years of age and adults experience symptomatic illness more frequently while most children under the age of 6 years are asymptomatic. Infected people are considered contagious during the 2 weeks prior through 1 week following onset of jaundice. Asymptomatic individuals can also transmit HAV.
Testing for Acute HAV: A positive serologic test for anti-HAV IgM is needed to confirm acute HAV infection and should only be ordered when symptoms of acute HAV infection are present. Liver function tests (LFTs) should also be ordered for patients with suspected acute HAV infection. PDPH discourages use of HAV IgM testing for asymptomatic patients who are being screened for immunity or chronic Hepatitis B or C infection, as false positive results occur.
Vaccination of High Risk Patients: For persons aged 12 months and older, safe and highly effective HAV vaccine is available to prevent infection. Due to their increased risk of exposure to HAV, PDPH encourages providers to routinely vaccinate the following patients for HAV in accordance with the Advisory Committee on Immunization Practice (ACIP) recommendations (2 doses given 6–18 months apart).
• Patients who identify as MSM or who have a sex partner identifying as MSM
• Patients who are currently homeless or who have had periods of homelessness in the past
• Users of injection and non-injection drugs
Vaccination status can be verified by accessing the Philadelphia Immunization Information System (KIDS Plus) at https://kids.phila.gov or calling 215-685-6784. For help obtaining vaccine for uninsured high risk adults, contact the PDPH Vaccines for Adults at Risk (VFAAR) program at 215-685-6424.
Post-exposure Prophylaxis: HAV vaccine can also prevent exposed persons from becoming sick. Any close contacts, including household members and sexual partners, of an acute HAV case should receive post-exposure prophylaxis within 2 weeks of their last exposure. Exposed individuals aged 1–59 years should receive one dose of single-antigen HAV vaccine. Hepatitis A immune globulin (IG) should be used for exposed individuals aged 60 years and older, children aged less than 12 months, immunocompromised persons, persons with chronic liver disease, and for those who are allergic to the vaccine or a vaccine component.
Originally released by the Philadelphia Department of Public Health on October 12, 2017.
