Hepatitis A Outbreak in West Virginia, 2018

West Virginia has had 98 confirmed cases of Hepatitis A virus (HAV) infection so far in 2018 (Figure 1). This increase in cases has primarily been among injection and non-injection drug users, homeless individuals, those who have been recently incarcerated, and individuals co-infected with hepatitis C.

HAV is a RNA picornavirus which can produce either asymptomatic or symptomatic infection in humans after an average incubation period of 28 days (range: 15–50 days). Symptoms include abrupt onset of fever, malaise, anorexia, nausea, abdominal discomfort, dark urine, and jaundice. Person-to-person transmission is through fecal-oral route and peak infectivity of infected persons occurs during the 2-week period before onset of jaundice or elevation of liver enzymes, when concentration of virus in stool is highest. ^1-3

Sequencing of the virus has linked it to the multi-state HAV genotype IB outbreak that has been ongoing since 2017 which has affected Kentucky, California, Indiana, Michigan and Utah. In response to the outbreak the CDC has encouraged state health departments to provide HAV vaccine to people who are homeless, people who use injection and non-injection drugs, vaccination for anyone with ongoing, close contact with people who are homeless or people who use injection and non-injection drugs.

There are two inactivated single agent HAV vaccination (HAVRIX ®, VAQTA ®) and one inactivated combination (with Hepatitis B virus) vaccination (TWINRIX ®) currently licensed for use in the United States. Current ACIP recommendations ⁴ include vaccination for the following groups:

All children at age 1 year
Travelers to countries that have high rates of hepatitis A
Family members and caregivers of recent adoptees from countries where hepatitis A is common
Men who have sexual contact with other men
People who use injection and non-injection illegal drugs
People with chronic (lifelong) liver diseases, such as hepatitis B or hepatitis C
People who are treated with clotting-factor concentrates
People who work with hepatitis A infected animals or in a hepatitis A research laboratory

In addition, post exposure prophylaxis is recommended for unvaccinated individuals who have had exposure in the last 2 weeks with Hepatitis A vaccine for people aged 1-40 years or HAV immunoglobulin for those who fall outside that age window.

West Virginia has established three vaccination clinics to provide vaccination to at risk populations. Weekly updates on the case counts can be found at the WV DOH website.

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