Takako Utsumi

Novel Subgenotypes of Hepatitis B Virus Genotypes C and D in Papua, Indonesia

ABSTRACT Eight genotypes (A to H) and nine subtypes (adw2, adw4, ayw1, ayw2, ayw3, ayw4, adrq+, adrq−, and ayr) of hepatitis B virus (HBV) have been identified worldwide. They appear to be associated with geographical distribution, virological characteristics, and possibly clinical outcomes. We performed sequence analysis of part of the S gene and the entire precore/core gene of HBV isolates obtained from HBsAg-positive blood donors in Papua Province, Indonesia. Phylogenetic analysis of the S gene sequences revealed that 23 (85.2%) of the 27 HBV isolates tested belonged to genotype C (HBV/C) and 2 (7.4%) each to HBV/B and HBV/D. Interestingly, 19 (82.6%) of the 23 isolates of HBV/C clustered in a branch that was distinct from the previously reported subgenotypes C1 to C5 (HBV/C1 to HBV/C5). Similarly, two isolates of HBV/D clustered in a branch distinct from the reported subgenotypes HBV/D1 to HBV/D5. Phylogenetic analysis of the entire precore/core gene confirmed the consistent presence of the distinct branches in HBV/C and HBV/D. We therefore propose novel subgenotypes designated HBV/C6 and HBV/D6. The majority of HBV/C6 isolates in Papua had alanine at positions 159 and 177 (A159/A177) in the HBsAg. A159/A177 is different from the determinants for adrq+ (A159/V177), found throughout Asia, and adrq− (V159/A177), found in New Caledonia and Polynesia, possibly representing a unique antigenic group (provisionally referred to as adrq indeterminate). In conclusion, we have identified two novel HBV subgenotypes, HBV/C6 and HBV/D6, the first of which is the most prevalent subgenotype of HBV in Papua, Indonesia.

Complete Genome Sequence and Phylogenetic Relatedness of Hepatitis B Virus Isolates in Papua, Indonesia

ABSTRACT Each hepatitis B virus (HBV) genotype and subgenotype is associated with a particular geographic distribution, ethnicity, and anthropological history. Our previous study showed the novel HBV subgenotypes C6 (HBV/C6) and D6 (HBV/D6), based on the S gene sequences of isolates in Papua, Indonesia. The present study investigated the complete genome sequence of 22 strains from Papua and subjected them to molecular evolutionary analysis. A phylogenetic analysis revealed that 9 out of 22 strains were classified as HBV/C6, 3 strains as HBV/D6, and 9 strains as HBV/B3. A particular strain positioned between HBV/B3 and HBV/B5 remained unclassifiable into any known subgenotypes. This strain showed high homology with HBV/C5 from the Philippines in the core region and was thought to have undergone genetic recombination with HBV/C5. Further studies are needed to determine whether this strain belongs to a new subgenotype of HBV/B. Based on the amino acid alignment, HBV/C6 has subgenotype specific variations (G18V and V47M) in the S region. HBV/C6 strains were more closely related in terms of evolutionary distance to strains from the east Asia and Pacific regions than those found in southeast Asia. HBV/D6 strains were most closely related to strains from the Western countries (HBV/D3) rather than those from Asia and Papua New Guinea. In conclusion, we have confirmed by complete sequence analysis that two novel HBV subgenotypes, HBV/C6 and HBV/D6, are prevalent in Papua, Indonesia.

Molecular epidemiological study of hepatitis viruses in Ismailia, Egypt

The hepatitis virus is hyperendemic in Egypt, western Asia and Africa. In Egypt, most studies have been carried out in the regions of the upper and lower Nile Delta, and so little is known about other parts of the country. Our project aimed to clarify the carrier rate of various hepatitis viruses in the northeastern province of Ismailia. A total of 214 patients with elevated liver enzymes were enrolled in this study. Sera were collected in Ismailia hospital. We conducted a serological and molecular-based survey of hepatitis viruses, including their genetic variability and genotype-related differences. There were 10 (4.7%) cases positive for hepatitis B surface antigen (HBsAg), and 156 (72.9%) positive for anti-hepatitis C virus antibody (HCV-Ab). Phylogenetic analysis showed that genotype C of HBV and genotype 4a of HCV were prevalent. Hepatitis D virus RNA was not detected in HBsAg carriers. Although anti-hepatitis E virus IgM antibody was positive in 5 cases (2.3%), no case was positive for its RNA. Among 54 cases negative for HBsAg and HCV-Ab, HBV-DNA was detected in 35 cases (65%). Our results revealed that HBV and HCV, including occult HBV infection, are widespread and related to liver diseases in Ismailia province, Egypt.

Serologic and Molecular Characteristics of Hepatitis B Virus among School Children in East Java, Indonesia

Universal childhood hepatitis B vaccination was introduced in Indonesia in 1997; by 2008, coverage was estimated to be 78%. This study aimed to investigate the serologic status and virologic characteristics of hepatitis B virus (HBV) among the children in East Java. A total of 229 healthy children born during 1994-1999 were enrolled in this study. Overall, 3.1% were positive for hepatitis B surface antigen (HBsAg) and 23.6% were positive for antibody to HBsAg (anti-HBs). HBV DNA was detected in 5 of 222 HBsAg-negative carriers, which were suggested to be cases of occult HBV infection. A single amino substitution (T126I) in the S region was frequently found. HBV infection remains endemic, and the prevalence of anti-HBs remains insufficient among children in East Java, Indonesia.

Clinical and virological characteristics of hepatitis B or C virus co-infection with HIV in Indonesian patients†

Hepatitis virus‐related liver disease increases substantially the mortality rate of patients with HIV on highly active antiretroviral therapy (HAART). Therefore, early diagnosis of hepatitis B virus (HBV) and hepatitis C virus (HCV) is important. However, the prevalence of HBV and HCV infection in Indonesian patients infected with HIV is unknown. Therefore, this study examined the molecular and clinical characteristics of HBV and HCV in 126 patients infected with HIV, mostly on HAART, at Dr. Sardjito Hospital, Yogyakarta, Indonesia. The rates of triple infection, HIV/HCV co‐infection, HIV/HBV co‐infection, and mono‐infection were 4.8%, 34.1%, 3.2%, and 57.9%, respectively. Seven HCV genotypes were detected, with genotypes 1a, 1b, 1c, 3a, 3k, 4a, and 6n found in 23 (52%), 1 (2%), 4 (9%), 5 (11%), 7 (16%), 3 (6%), and 1 (2%) patients, respectively, indicating multiple modes of transmission. HBV‐DNA was detected in 2/10 patients with hepatitis B surface antigen; both patients were HAART naive. Univariate analysis revealed that male sex, higher education level, injection drug use, sexual contact, alanine aminotransferase ≥40 IU/L, and aspartate aminotransferase‐to‐platelet ratio index > 0.5 were associated with HCV co‐infection. In multivariate analysis, injection drug use (OR: 26.52; 95% CI: 3.52–199.54) and alanine aminotransferase ≥40 IU/L (OR: 6.36; 95% CI: 1.23–32.89) were independently associated with HCV co‐infection. HCV co‐infection was common among Indonesian patients infected with HIV, particularly among injecting drug users, and was a risk factor for disease progression of HIV. J. Med. Virol. 84:857–865, 2012.

Hepatitis B and C virus infection among hemodialysis patients in yogyakarta, Indonesia: Prevalence and molecular evidence for nosocomial transmission

Hemodialysis patients are at an increased risk of acquiring hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. However, the prevalence of hepatitis viral infection and its genotype distribution among hemodialysis patients in Indonesia are unclear. In order to investigate these issues and the possibility of nosocomial transmission, 161 hemodialysis patients and 35 staff members at one of the hemodialysis unit in Yogyakarta, Indonesia, were tested for serological and virological markers of both viruses. HBV surface antigen (HBsAg) was detected in 18 patients (11.2%) and in two staff members (5.7%). Anti‐HCV was detected in 130 patients (80.7%) but not in any staff members. Occult HBV and HCV infection were detected in 21 (14.7%) and 4 (12.9%) patients, respectively. The overall prevalence rates of HBV and HCV infection among patients were 24.2% and 83.2%, respectively. HCV infection was independently associated with hemodialysis duration and the number of blood transfusions. Phylogenetic analysis revealed that 23 of 39 tested HBV strains (59%) were genotype B, 11 (28.2%) were genotype C, and 5 (12.8%) were genotype A. HCV genotype 1a was dominant (95%) among 100 tested HCV strains. Nosocomial transmission was suspected because the genotype distribution differed from that of the general population in Indonesia, and because the viral genomes of several strains were identical. These findings suggest that HBV and HCV infection is common among hemodialysis patients in Yogyakarta, and probably occurs through nosocomial infection. Implementation of strict infection‐control programs is necessary in hemodialysis units in Indonesia. J. Med. Virol. 85:1348–1361, 2013.

Another novel subgenotype of hepatitis B virus genotype C from papuans of Highland origin.

Hepatitis B virus (HBV) genotypes and subtypes have been identified worldwide. As HBV genotypes/subtypes, the HBV subgenotypes seem to be associated with their geographical distribution and ethnic origin. A previous study showed the novel HBV subgenotype C6 based on the complete genome sequences of isolates in Papua, Indonesia. In the present study, further characterization of HBV in Jayapura (capital of Papua Province), particularly from native people of Papua originating from the highland (highland Papuans) and those from the lowland (lowland Papuans) were examined. Of 32 HBV isolates from both highland and lowland Papuan blood donors with HBsAg positive, part of the S gene and the core gene sequences were analyzed. Analyses of some isolates from highland Papuans were confirmed by the complete genome sequences. Most HBV isolates were classified into genotype C (78.1%), followed by genotype B (18.8%), and genotype D (3.1%). The subtype adr was predominant (71.9%), followed by adw2 (25.1%), and ayw2 (3.1%). As with previous findings, phylogenetic analyses revealed that most HBV isolates from Papuans, C/adr, belonged to subgenotype C6. Interestingly, some C/adr isolates from highland Papuans formed a distinct cluster from all reported subgenotypes of HBV/C, and they differed from HBV/C1‐C10 by 4.2–7.2% over the complete genome. SimPlot analysis showed no evidence of recombination with HBV/C1–C10. The isolated life and closed social systems of highland Papuans, even though some have been moving to Jayapura, likely contribute to the formation of this unique cluster of infection with a novel subgenotype of HBV, named C11. J. Med. Virol. 83:225–234, 2011.

Ultradeep Sequencing for Detection of Quasispecies Variants in the Major Hydrophilic Region of Hepatitis B Virus in Indonesian Patients

ABSTRACT Quasispecies of hepatitis B virus (HBV) with variations in the major hydrophilic region (MHR) of the HBV surface antigen (HBsAg) can evolve during infection, allowing HBV to evade neutralizing antibodies. These escape variants may contribute to chronic infections. In this study, we looked for MHR variants in HBV quasispecies using ultradeep sequencing and evaluated the relationship between these variants and clinical manifestations in infected patients. We enrolled 30 Indonesian patients with hepatitis B infection (11 with chronic hepatitis and 19 with advanced liver disease). The most common subgenotype/subtype of HBV was B3/adw (97%). The HBsAg titer was lower in patients with advanced liver disease than that in patients with chronic hepatitis. The MHR variants were grouped based on the percentage of the viral population affected: major, ≥20% of the total population; intermediate, 5% to <20%; and minor, 1% to <5%. The rates of MHR variation that were present in the major and intermediate viral population were significantly greater in patients with advanced liver disease than those in chronic patients. The most frequent MHR variants related to immune evasion in the major and intermediate populations were P120Q/T, T123A, P127T, Q129H/R, M133L/T, and G145R. The major population of MHR variants causing impaired of HBsAg secretion (e.g., G119R, Q129R, T140I, and G145R) was detected only in advanced liver disease patients. This is the first study to use ultradeep sequencing for the detection of MHR variants of HBV quasispecies in Indonesian patients. We found that a greater number of MHR variations was related to disease severity and reduced likelihood of HBsAg titer.

Mutations within enhancer II and BCP regions of hepatitis B virus in relation to advanced liver diseases in patients infected with subgenotype B3 in Indonesia

Studies on the characteristics of mutations within the hepatitis B virus (HBV) genome, their roles in the pathogenesis of advanced liver diseases, and the involvement of host properties of HBV‐infected individuals have not been conducted in subgenotype B3‐infected populations. For addressing this issue, 40 cases with HBV surface antigen (HBsAg)—positive advanced liver diseases, including advanced liver cancer and cirrhosis (male 31, female 9, age 54.4 ± 11.6‐year‐old), were collected and compared with 109 cases with chronic hepatitis B (male 71, female 38, age 38.0 ± 13.4‐year‐old). Mutations in enhancer II (Enh II) and basal core promoter (BCP)/precore regions were analyzed by PCR‐direct sequencing method. HBV viral load was examined by real‐time PCR. For all examined regions, the prevalence of mutation was significantly higher in cases with advanced liver diseases. Multivariate analysis showed that, in patients older than 45 years, C1638T and T1753V mutations constituted independent risk factors for the advancement of liver diseases. The presence of C1638T and T1753V mutations may serve as predictive markers for the progression of liver diseases in Indonesia and other countries, where subgenotype B3 infection is prevalent. J. Med. Virol. 84:44–51, 2011.

Hepatitis B virus infection in Indonesia

Approximately 240 million people are chronically infected with hepatitis B virus (HBV), 75% of whom reside in Asia. Approximately 600000 of infected patients die each year due to HBV-related diseases or hepatocellular carcinoma (HCC). The endemicity of hepatitis surface antigen in Indonesia is intermediate to high with a geographical difference. The risk of HBV infection is high in hemodialysis (HD) patients, men having sex with men, and health care workers. Occult HBV infection has been detected in various groups such as blood donors, HD patients, and HIV-infected individuals and children. The most common HBV subgenotype in Indonesia is B3 followed by C1. Various novel subgenotypes of HBV have been identified throughout Indonesia, with the novel HBV subgenotypes C6-C16 and D6 being successfully isolated. Although a number of HBV subgenotypes have been discovered in Indonesia, genotype-related pathogenicity has not yet been elucidated in detail. Therefore, genotype-related differences in the prognosis of liver disease and their effects on treatments need to be determined. A previous study conducted in Indonesia revealed that hepatic steatosis was associated with disease progression. Pre-S2 mutations and mutations at C1638T and T1753V in HBV/B3 have been associated with advanced liver diseases including HCC. However, drug resistance to lamivudine, which is prominent in Indonesia, remains obscure. Although the number of studies on HBV in Indonesia has been increasing, adequate databases on HBV infection are limited. We herein provided an overview of the epidemiology and clinical characteristics of HBV infection in Indonesia.