[The estimation of the hepatitis E proportion in the etiological structure of acute viral hepatitis in certain regions of of Kyrgyzstan.]

Despite the fact that the Kyrgyz Republic (KR) belongs to the highly endemic regions of the world for hepatitis E, the true extent of the spread of this infection in the country remains poorly understood. It was estimated the prevalence of serological markers of hepatitis E virus (HEV) infection among patients with acute viral hepatitis (AVH) from the regions of the Kyrgyz Republic with a high level of seroprevalence previously established by us. Blood sera samples of hepatitis patients who were admitted to hospitals of Kyrgyzstan in the period 2018-2019 were examined by the enzyme immunoassay method using the kits «DS-ELISA-Anti-HEVIgG¼ and «DS-ELISA-ANTI-HEV-IgM¼ (RPC Diagnostic Systems, Russia). IgG and IgM antibodies to HEV were detected in 103 of 344 studied samples (29.9%). Most often, seropositive specimens were detected among people of age groups under 20 and over 40 years old. Hepatitis with the fecal-oral mode of transmission was dominated in the structure of AVH: the specific gravity of hepatitis E was 47.9%, hepatitis A - 35.32%. Markers of mixed infections with other hepatitis viruses have been detected in 40.4% IgM-positive individuals. Thus, high prevalence of serological markers of HEV infection in the territory of Kyrgyzstan during the interepidemic period had been shown. The necessity of including the determination of serological markers of hepatitis E into the algorithm for the comprehensive diagnosis of AVH in patients of all age groups with liver pathology had been confirmed.

[Belgorod region - the territory endemic for hepatitis E.]

INTRODUCTION: Belgorod region is the territory with the highest incidence of hepatitis E in the Russian Federation. OBJECTIVES: The aim of the study was to comprehensively characterize the circulation of hepatitis E virus (HEV) in the Belgorod region, including the study of population immunity to the virus, determining the prevalence of infection among the pig population and analysis of the genetic diversity of HEV from patients and animals. MATERIAL AND METHODS: Serum samples of a conditionally healthy population (n = 2027) of all age groups were tested for anti-HEV IgG and IgM by ELISA with commercial assays. HEV RNA was determined in fecal samples from pigs aged 2-4 months (n = 526), in sewage samples from pig farms (n = 10), as well as in stool samples from patients with hepatitis E (n = 6) using reverse transcription polymerase chain reaction (RT-PCR). Phylogenetic analysis was performed for an amplified 300 nt fragment corresponding to HEV open reading frame 2. RESULTS AND DISCUSSION: The prevalence of anti-HEV IgG in general population averaged 16.4% (95% CI: 14.8-18.1; 332/2027). The proportion of individuals who had both anti-HEV IgM and IgG averaged 2.8% (95% CI: 2.2-3.6; 57/2027). The incidence rate of anti-HEV IgG increased with age, from 2.8% (95% CI: 1.3-5.8) in children aged 1-14 years to 40.1% (95% CI: 34.9-45.6) in people 70 years or older. The detection rate of HEV RNA in pigs was 20% (95% CI: 16.8-23.6; 105/526). HEV RNA was detected in 2 out of 10 sewage samples. The HEV sequences isolated from patients with hepatitis E, pigs, and sewage samples in Belgorod region belonged to the HEV genotype 3, had a 95-100% homology, and formed common clusters on a phylogenetic tree. CONCLUSIONS: The high prevalence of HEV in pigs population has led to the formation of an endemic territory in the Belgorod region, which is the center of pig breeding. Measures aimed at reducing the circulation of HEV among pig population and decontamination of sewage from pig farms are necessary to control HEV infection.