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Serum samples obtained from 289 first-time and 114 repeat donors at the Blood Center of Mongolia (MBC) were tested for serological and molecular markers of hepatitis B virus (HBV), hepatitis C virus (HCV), and hepatitis delta virus (HDV) infections. Among the 403 blood donors, 33 (8.2%), 21 (5.2%), and 27 (6.7%) tested positive for hepatitis B surface antigen (HBsAg) and/or HBV DNA, HCV RNA, and HDV RNA, respectively. Collectively, 55 donors were viremic for one or more of these viruses, and included 54 first-time donors (18.7%) and 1 repeat donor (0.9%) ( P < 0.0001). One discrepant case with HBsAg detectable only at MBC was negative for HBsAg, HBV DNA and anti-HBc in this study. Four donors who were HCV-viremic in this study were negative for anti-HCV by the MBC method. Further efforts to increase the sensitivity and specificity of the currently-used tests are urgently required in Mongolia. Three donors who were positive for anti-HBc and anti-HDV but negative for HBsAg, had both HBV DNA and HDV RNA. This suggests that introduction of a new anti-HDV serological test is useful for not only HDV screening but also HBV screening of anti-HBc-positive, HBsAg negative donors, considering a possibility of viral interference by coexisting HDV. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) infects humans and a wide variety of other mammalian hosts. Recently, HEV strains belonging to genotype 8 (G8) within the Orthohepevirus A species of the Hepeviridae family, were identified in Bactrian camels (Camelus bactrianus) in China. The Bactrian camel (also known as the Mongolian camel) is native to the steppes of Central Asia. However, the HEV strains of Mongolian camels have not been examined. Among 200 serum samples from domestic Bactrian camels raised on 6 farms, in 6 soums in 3 provinces; 71 (35.5 %) were positive for anti-HEV IgG, with prevalence differing by farm (soum) (4.2-75.0 %); and 2 camels (1.0 %) that had been raised in Bogd, Bayankhongor Province, which had the highest seroprevalence among the six studied areas, were positive for HEV RNA. The two HEV strains (BcHEV-MNG140 and BcHEV-MNG146) obtained from the viremic camels in the present study shared 97.7 % nucleotide identity. They were closest to the reported G8 Chinese camel HEV strains but differed from them by 13.9-14.3 % over the entire genome, with a nucleotide difference of 24.0-26.5 % from the reported G1-G7 HEV strains. A phylogenetic tree indicated that the BcHEV-MNG140 and BcHEV-MNG146 strains were located upstream of a clade consisting of the Chinese camel HEV strains and formed a cluster with them, with a bootstrap value of 100 %, suggesting that they may represent a novel subtype within G8. These results indicate a high prevalence of HEV infection in Mongolian camels and suggest that the variability of camel HEV genomes is markedly high., (Copyright © 2021 Elsevier B.V. All rights reserved.)

One hundred ten consecutive patients (60 males and 50 females; age, mean +/- standard deviation [SD], 22.6 +/- 6.4 years; range 16-48 years) who were clinically diagnosed with sporadic acute hepatitis between December 2004 and January 2005 in Ulaanbaatar, Mongolia, were studied. IgM antibodies to hepatitis A virus were detected in 18 patients (16.4%), IgM antibodies to hepatitis B core (anti-HBc IgM) in 38 patients (34.5%) including two patients with concurrent hepatitis delta virus (HDV) infection, and hepatitis C virus RNA in nine patients (8.2%). There were 30 hepatitis B virus (HBV) carriers who had detectable hepatitis B surface antigen and antibodies to HDV but were negative for anti-HBc IgM, suggesting that they acquired type D acute hepatitis due to superinfection of HDV on a background of chronic HBV infection. None had IgM antibodies to hepatitis E virus (HEV). Consequently, 16.4, 32.7, 6.4, 1.8, and 27.3% of the patients were diagnosed as having acute hepatitis of type A, B, C, type B + D (HBV/HDV coinfection), and type D (superinfection of HDV), respectively. The cause of hepatitis was not known in the remaining 17 patients (15.5%). All 18 HAV isolates were genotyped as IA, all 9 HCV isolates were genotyped as 1b, and all 32 HDV isolates were classified into genotype I. The distribution of HBV genotypes among the 67 HBV isolates was A (1.5%, n = 1) and D (98.5%, n = 66). The present study indicates that de novo infections of HAV, HBV, HCV, and HDV are prevalent among young adults in Mongolia., (Copyright 2006 Wiley-Liss, Inc.)

Mongolia is known for its high endemicity for hepatitis B virus (HBV), hepatitis C virus (HCV), and hepatitis delta virus (HDV) infections among apparently healthy individuals. However, there are little or no data on the prevalence and genotype distribution of HBV, HCV, and HDV among patients with chronic liver disease in Mongolia. Therefore, serum samples obtained in 2004 from 207 patients (age, mean+/-standard deviation, 51.0+/-11.9 years) including those with chronic hepatitis (n=90), liver cirrhosis (n=41), and hepatocellular carcinoma (n=76) were tested for serological and molecular markers of HBV, HCV, and HDV infections. Of the 207 patients, 144 (69.6%), 106 (51.2%), and 117 (56.5%) tested positive for hepatitis B surface antigen (HBsAg) and/or HBV DNA, HCV RNA, and HDV RNA, respectively. Collectively, 172 patients (83.1%) were viremic for one or more of these viruses, including dual viremia of HBV/HDV (26.6%) or HBV/HCV (7.7%) and triple HBV/HCV/HDV viremia (30.0%). Of note, triple ongoing infection was significantly more frequent among patients with hepatocellular carcinoma than among those with chronic hepatitis (63.2% vs. 14.4%, P<0.0001). One hundred sixty patients (77.3%) had a history of blood transfusion and/or surgery. The distribution of HBV genotypes among the 116 HBV-viremic patients was: A (0.9%), B (0.9%), C (6.0%), D (88.8%), and C plus D (3.4%). All 117 HDV isolates were classified into genotype I. The 106 HCV RNA-positive samples were typed as genotype 1b (92.5%), 2a (0.9%), or 1b plus 2a (6.6%); mixed infection of two distinct HCV genotypes was found exclusively in the patients with hepatocellular carcinoma., (Copyright (c) 2005 Wiley-Liss, inc.)

A previous study revealed a high prevalence of hepatitis B surface antigen (HBsAg) and hepatitis delta virus (HDV) RNA among 249 apparently healthy individuals (mean+/-standard deviation age, 48.4+/-13.9 years; 126 males and 123 females) in Ulaanbaatar, Mongolia. To investigate further the prevalence of HDV infection there, the same serum samples obtained from the cohort were tested for the presence of immunoglobulin G (IgG) class antibody to HDV (anti-HDV) by a newly developed enzyme-linked immunosorbent assay using recombinant hepatitis delta antigen protein expressed in the pupae of silkworm as the antigen probe. Anti-HDV was detected in 42 persons (16.9%), among whom 22 (52.4%) were positive for HBsAg and 20 (47.6%) had detectable HDV RNA. Among 170 persons with anti-HBc in the absence of HBsAg, 20 (11.8%) tested positive for anti-HDV, and 1 of the 20 subjects was positive for HDV RNA. Of note, none of 55 anti-HBc-negative persons had anti-HDV, supporting the specificity of the anti-HDV assay. The optical density (OD) value of anti-HDV was significantly higher among HDV RNA-positive subjects (n=21) than among HDV RNA-negative subjects (n=21) (2.513+/-0.514 vs. 0.836+/-0.550, P<0.0001). The present study confirmed the extremely high prevalence of HDV infection in Mongolia, and identified a person who was positive for both anti-HDV and HDV RNA despite negativity for HBsAg and HBV DNA probably due to viral interference. The anti-HDV assay may be useful for further epidemiological studies on HDV infection in larger cohorts in urban and rural areas of Mongolia, where elucidation of the transmission route of HDV is required urgently., (Copyright (c) 2005 Wiley-Liss, Inc.)

The prevalence of infection with hepatitis A virus (HAV), HBV, HCV, HDV, and HEV was evaluated in 249 apparently healthy individuals, including 122 inhabitants in Ulaanbaatar, the capital city of Mongolia, and 127 age- and sex-matched members of nomadic tribes who lived around the capital city. Overall, hepatitis B surface antigen (HBsAg) was detected in 24 subjects (10%), of whom 22 (92%) had detectable HBV DNA. Surprisingly, HDV RNA was detectable in 20 (83%) of the 24 HBsAg-positive subjects. HCV-associated antibodies were detected in 41 (16%) and HCV RNA was detected in 36 (14%) subjects, none of whom was coinfected with HBV, indicating that HBV/HCV carriers account for one-fourth of this population. Antibodies to HAV and HEV were detected in 249 (100%) and 28 (11%) subjects, respectively. Of 22 HBV DNA-positive subjects, genotype D was detected in 21 subjects and genotype F was detected in 1 subject. All 20 HDV isolates recovered from HDV RNA-positive subjects segregated into genotype I, but these differed by 2.1 to 11.4% from each other in the 522- to 526-nucleotide sequence. Of 36 HCV RNA-positive samples, 35 (97%) were genotype 1b and 1 was genotype 2a. Reflecting an extremely high prevalence of hepatitis virus infections, there were no appreciable differences in the prevalence of hepatitis virus markers between the two studied populations with distinct living place and lifestyle. A nationwide epidemiological survey of hepatitis viruses should be conducted in an effort to prevent de novo infection with hepatitis viruses in Mongolia.