High prevalence of hepatitis delta virus infection detectable by enzyme immunoassay among apparently healthy individuals in Mongolia.

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.

Inoue J ，Takahashi M ，Nishizawa T ，Narantuya L ，Sakuma M ，Kagawa Y ，Shimosegawa T ，Okamoto H ... -  《JOURNAL OF MEDICAL VIROLOGY》

High prevalence of hepatitis B, C and delta virus infections among blood donors in Mongolia.

Tsatsralt-Od B ，Takahashi M ，Nishizawa T ，Inoue J ，Ulaankhuu D ，Okamoto H ... -  《ARCHIVES OF VIROLOGY》

Seroepidemiology of hepatitis B, delta and human immunodeficiency virus infections in Hamadan province, Iran: a population based study.

Amini S ，Mahmoodi MF ，Andalibi S ，Solati AA ... -  《-》

High prevalence of dual or triple infection of hepatitis B, C, and delta viruses among patients with chronic liver disease in Mongolia.

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.

Tsatsralt-Od B ，Takahashi M ，Nishizawa T ，Endo K ，Inoue J ，Okamoto H ... -  《JOURNAL OF MEDICAL VIROLOGY》

Infection with hepatitis A, B, C, and delta viruses among patients with acute hepatitis in Mongolia.

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.

Tsatsralt-Od B ，Takahashi M ，Endo K ，Buyankhuu O ，Baatarkhuu O ，Nishizawa T ，Okamoto H ... -  《JOURNAL OF MEDICAL VIROLOGY》