Decline in Hepatitis E Virus (HEV) Antibody Prevalence in Southeastern Germany, 1996 – 2011

Background: In the past decade, an increasing frequency of acute hepatitis E was noted in Germany. Most cases were unrelated to travel. Recently, a high prevalence (17%) of antibodies against hepatitis E was found in the adult German population. Although this alludes to an emerging infection, other reports indicated that the prevalence of anti-HEV might effectively have decreased over the past 50 years. To investigate the time trends of hepatitis E in southeastern Germany, we performed anti-HEV testing in sera taken from adults in 2011 and 1996.

Methods: Sera were primarily from inhabitants of the Upper Palatinate and Lower Bavaria. The final sample comprised 2,184 sera with 180 specimens in each of 6 age groups from 20 to 79 years. Specimens were randomly selected from all available samples of the respective age groups. Analysis of the place of residence was performed and demonstrated a comparable geographic distribution of samples 1996 vs. 2011. Testing was performed using anti-HEV-IgG ELISA (Axiom Diagnostics) and amended by immunoblot (recomLINE, Mikrogen). The test procedures were validated with WHO standard serum and a well characterized HEV genotype 3 positive sample.

Results: A significant difference in the anti-HEV-IgG prevalence was observed between the two groups: 34.3% of individuals were positive in the 2011 group as compared to 50.7% positives in the 1996 group (ELISA, p < 0.001). Results by immunoblot analysis were 14.5% (2011) vs. 20.5% (1996), p < 0.001. Differences were found in all age groups and were more pronounced from 20 to 39 years of age.

Conclusions: The prevalence of HEV antibodies seems to have considerably decreased in the past decades in the German population. The phenomenon of hepatitis E being an emerging disease is most probably due to an increasing awareness of the disease.