Epidemiology of Hepatitis E in 2017 in Bavaria, Germany

Abstract

In the last decade, the number of reported hepatitis E virus (HEV) infections in Germany, including Bavaria, has continued to rise. In order to identify risk factors associated with HEV infection, we investigated notified hepatitis E cases from Bavaria during 2017. The project “Intensified Hepatitis E Surveillance in Bavaria” included interviews with questionnaires, collection and genotyping of stool, serum and food samples. In addition, certain risk factors were examined in a sample comparison with healthy population using univariable analysis and logistic regression. In total, 135 hepatitis E cases from Bavaria were included in the analysis. Mean age for women was 46 (range 20–74) years and 47.5 (range 20–85) for men. 56 of the cases (41.5%) were asymptomatic. Among the symptomatic cases, both men and women were equally affected with symptoms like fever (16.3%), jaundice (18.8%) and upper abdominal pain (28.2%). 145 human samples (serum, stool) and 6 food samples were collected. 15.9% of the human samples (n = 23) were positive for HEV RNA by reverse-transcription quantitative real-time PCR (RT-qPCR). Identified risk factors significantly associated with hepatitis E were sausage consumption with odds ratio 9.6 (CI 1.3–70.1), fish with OR 2.2 (CI 1.1–4.4) and cat ownership with OR 1.9 (CI 1.3–3.0) in multivariable analyses. Further investigation is needed to confirm the role of fish in HEV transmission. Autochthonous HEV genotype 3 is prevalent in Bavaria and there could be more transmission routes contributing to the spread of HEV than previously known. Undercooked meat, offal, sausages, fish, shellfish and contact with animals and pets are possible sources for infection.

Molecular epidemiology and genotype-specific disease severity of hepatitis E virus infections in Germany, 2010–2019

“…These changes may be of clinical relevance but studies on the correlation between HEV-3 groups or subtypes and clinical courses yielded conflicting results [ 17–20 ] while infections of rabbits pointed to subtype-specific pathogenicity [ 21 ]. Data for Germany are scarce and either regionally limited or were published more than ten years ago [ 22 , 23 ].…”

Co-Circulation of Different Hepatitis E Virus Genotype 3 Subtypes in Pigs and Wild Boar in North-East Germany, 2019

“…Another report also confirmed the presence of infectious virus in pork liver sausage from southern France [ 52 ]. For Germany, several studies have been conducted that identified the consumption of offal and wild boar meat [ 5 ], ready-to-eat pork products [ 53 ] and sausages [ 54 ] as the highest risk factor for hepatitis E disease. Especially liver and liver sausages are main infectious food sources, which is reflected by high viral RNA prevalences ranging from 5.2% in blood [ 17 ], over 18% in liver up to 56.3% in bile samples of wild boars [ 55 ] as well as 13.5% in pig derived liver samples [ 56 ] and 22.0% in liver sausages from Germany [ 57 ].…”

Das Hepatitis-E-Virus – ein zoonotisches Virus: Verbreitung, Übertragungswege und Bedeutung für die Lebensmittelsicherheit

“…Auch aus der Schweiz ist ein ähnlicher Erkrankungsfall aufgeklärt worden, der nach dem Verzehr einer anderen Wurstart mit roher Schweineleber aufgetreten war [ 16 ]. Für Deutschland wurden verschiedene Fall-Kontroll-Studien durchgeführt, die auf den Verzehr von Wild und Innereien [ 17 ], Schweineleber, Schweine- und Wildschweinfleisch [ 18 ] sowie Wurstprodukten [ 19 ] als höchsten Risikofaktor für eine Hepatitis-E-Erkrankung hinweisen.…”