Epidemiologic estimates of hepatitis E virus infection in European countries.

Objectives: Reliable epidemiologic estimates of Hepatitis E Virus (HEV) infection and evidence on factors determining country-differences are sparse. We systematically assessed and extracted research data on three HEV infection markers and identified factors influencing HEV-positivity to generated adjusted EU/EEA country-specific estimates by a meta-analysis.

Methods: Reports on HEV published 2005-2015 for EU/EEA countries were obtained from PubMed, Embase, Scopus, and Cochrane databases. Utilizing data on anti-HEV IgG, IgM and HEV-RNA we estimated HEV sero-prevalence, recent and acute HEV infections. Respective magnitude of factors influencing HEV-positivity was characterized using deviance. Country-specific estimates were generated by multivariable logistic regression.

Results: Of 4980 records, 165 covering 18 EU/EEA countries met inclusion criteria. The majority of collected data were published for Germany, France, United Kingdom, The Netherlands, and Spain. Most influential factor for anti-HEV IgG was the assay used (42% of total deviance); IgM and HEV-RNA were predominately determined by studied population (34%, 74%). Adjusted country-specific estimates for anti-HEV IgG ranged from 1.82%-17.06%, IgM 0.14%-6.54%, and HEV-RNA 0.00%-0.10%. No general geographical pattern of HEV-positivity was visible.

Conclusions: Our analysis revealed a high heterogeneity regarding data availability and HEV-seropositivity across EU/EEA countries. Determinants of HEV-estimates including assay are to be considered when interpreting HEV-epidemiology and its burden.