All people experiencing homelessness who are aged ≥1 year should be routinely immunized against hepatitis A virus (HAV), according to a recommendation published in the Morbidity and Mortality Weekly Report from the Centers for Disease Control and Prevention. This recommendation was approved at the October 2018 Advisory Committee on Immunization Practices (ACIP) meeting.
The hepatitis A (HepA) vaccination is recommended for children aged 12 to 23 months, for people at increased risk for HAV infection, and for those who want to become immune. People experiencing homelessness are at a higher risk for HAV infection and severe infection-associated outcomes. To develop a vaccination recommendation for this population, the ACIP Hepatitis Vaccines Work Group conducted a systematic review of evidence for administering vaccines to people experiencing homelessness.
The HepA vaccine is highly immunogenic, with >95% of immunocompetent adults developing protective antibodies within 4 weeks of receiving 1 dose of the vaccine.
Primarily, people acquire HAV infections by the fecal-oral route through either person-to-person transmission or ingestion of contaminated food or water. Implementing other strategies to prevent HAV infection, such as strict hand hygiene, is challenging due to the living conditions of people experiencing homeless. This makes routine HepA vaccines in this population the best strategy for prevention.
ACIP recommends that routine HepA vaccination should be integrated into facilities that already provide health care for the homeless population.
“HepA vaccination of persons experiencing homelessness will provide individual protection and increase herd immunity over time, reducing the risk of large-scale, person-to-person outbreaks in this population,” the researchers wrote.
Doshani M, Weng M, Moore KL, Romero JR, Nelson NP. Recommendations of the Advisory Committee on Immunization Practices for use of hepatitis A vaccine for persons experiencing homelessness. MMWR Morb Mortal Wkly Rep. 2019;68:153-156.