Hepatitis A and B among newly arrived refugees: Vaccinate all, or test first for immunity?

When screening newly arrived refugees, physicians must decide whether to vaccinate against hepatitis A and B at first encounter, thereby minimising missed opportunity, or to test for immunity and vaccinate only the susceptible, minimising unnecessary intervention. Better knowledge of hepatitis A and B immunity in refugee populations from different parts of the world is needed.

Overseas and domestic medical records of refugees from Africa, Asia, and the Middle East who entered Marion County (Indiana) between 1 September 2016 and 31 December 2017 were reviewed.

Of 1191 refugees, 1163 and 1153 were tested for immunity to hepatitis A and B respectively. Among <19 year-olds, immunity to hepatitis A ranged from 52.1% to 79.6%, and immunity to hepatitis B ranged from 75.5% to 87.6%. Among ≥19 year-olds, immunity to hepatitis A was greater than 90% for each of the three regions, whereas immunity to hepatitis B ranged from 19.3% to 94.4%. 96% of refugees in the subset of Burmese ≥19 years old were immune to hepatitis B. Of individuals immune to hepatitis B, immunity was due to vaccination in 94.1% of <19 year-olds and 57.4% of ≥19 year-olds. 10% of refugees with at least three documented doses of hepatitis B vaccine were negative for hepatitis B surface antibody. 34.1% of uninfected refugees with no documented doses of hepatitis B vaccination were positive for hepatitis B surface antibody.

It is reasonable to begin hepatitis A vaccination of <19 year-olds in this refugee population at first encounter but to test first for hepatitis A susceptibility before vaccinating those ≥19 years old. Similarly delaying hepatitis B vaccination might be appropriate only for a subset of Burmese adults.