[The value of screening serology in anti-hepatitis A vaccination of travelers]

Abstract

To select the travellers most likely to benefit from anti-hepatitis A (HA) antibody testing, the following criteria have been proposed: (A) being born before 1945, (B) a stay over 1 year in a developing country or (C) a history of jaundice. We present a prospective study to assess the practical use of these criteria. Following a recent survey in the general population of Lausanne showing HA seroprevalence of 52.6% in the age group over 45, we included an A1 criterion (A extended to birth before 1950). Anti-HA IgG testing and a questionnaire were proposed to all travellers presenting one or more criteria.

Results: Out of 1187 consecutive travellers, 176 (14.8%) had one or more criteria (219 [18.5%] when A1 was used). Criteria A applied to 8.5% of all travellers, A1 to 13.8%, B to 6.3% and C to 3.1%. Only 3% of travellers had more than one criterion. Overall seroprevalence among the selected group was 48.3%. Seroprevalence of travellers below 60 years old was under 30%, unless a second criterion was present in which case seroprevalence was 10% higher. Eighty percent of travellers with a history of jaundice were found to be positive. The use of the recommended criteria spared 94 travellers (46.3% of those tested and 7.9% of all travellers) unnecessary immunisation. Among travellers older than 60 years, a 30% economy on the total sum for immunising all of them, without any prior testing was realised.

Conclusions: Among the population of travelers consulting our travel clinic, the seroprevalence for HA is lower than in the general population. We recommend that testing should be proposed only to travellers aged over 60, or with a history of jaundice, or to those with a combination of 2 out of 3 criteria.