Circulation of Hepatitis E in Israel: HEV-G3 in Pigs, HEV-G7 in Dromedary Camels, HEV-G1 in Sporadic Viral Hepatitis Patients and High HEV Seroprevalence in Specific Human Populations -

Rachel Shirazi ¹ Ravit Bassal ² Shaul Pozzi ^3,4 Dan David ⁴ Marina Wax ¹ Itay Bar-Or ¹ Efrat Asulin ¹ Yaniv Lustig ¹ Eli Schwartz ^5,6 Ella Mendelson ^1,6 Tamy Shohat ^2,6 Orna Mor ^1,6

¹Central Virology Laboratory, Ministry of Health, Israel
²Israel Center for Disease Control, Ministry of Health, Israel
³Dipartimento Scienze Veterinarie, Universita’ di Torino, Italy
⁴Veterninary services, Agriculture Ministry, Israel
⁵Tropical Diseases, Sheba Medical Center, Israel
⁶Sackler school of Medicine, Tel Aviv University, Israel

Introduction: Hepatitis E virus (HEV) is an emerging cause for viral hepatitis worldwide. Eight HEV genotypes are currently known of which the non-zoonotic genotype 1 (HEV-G1) and the zoonotic (transmitted mainly by pigs) genotype 3 (HEV- G3) are common in developing and developed countries, respectively. HEV genotype 7 (HEV-G7) was recently identified in dromedary camels and in a chronic hepatitis patient.

Objectives: To assess HEV prevalence in humans and in domestic pigs and dromedary camels.

Methods: Human sera samples, collected between 2009 and 2018 from viral hepatitis patients (n=153), pig-farmers (n=24) and anonymous sera (deposited in the National Serum Bank) from Bedouins (n=305), Arabs (Muslims, n=320) and Jews (n=195) were assessed. Domestic pig (blood, n=141; fecal, n=79) and dromedary camel (blood, n=235) samples collected between 2016 and 2018 were also assessed. Anti-HEV IgG were detected by ELISA (Wantai, China); HEV RNA by RealStar (Altona, Germany).

Results: Prevalence of anti-HEV antibodies in pigs and camels was 75.9% (107/141) and 69.8% (60/86), respectively. Seropositivity rates were 21.6% (66/305), 15% (48/320) and 3.1% (6/195) among Bedouins, Muslim-Arabs and Jews, respectively, with rates increasing with age. Almost all (23/24) pig-farmers were anti- HEV positive. None were viremic or reported any previous clinical signs. HEV RNA was detected in pig blood (2.1%, 3/141), pig feces (22.9%, 18/79) pig sewage (50.0%, 4/8), camel sera (1.2%, 3/235) and in 4.5% (7/153) of viral hepatitis patients. HEV-G3, HEV-G7 were identified in pigs and camels while HEV-G1 was identified in patients.

Conclusion: This is the first report of HEV-G7 in camels in Israel. Along with the identified HEV-G3 sequences in pigs, this study suggests that various HEV genotypes are endemic in Israel. The rare HEV-G1 viral hepatitis cases were all imported. The impact of all these findings on public health should be further explored, especially as high seroprevalence was identified in specific populations.