The ecology of hepatitis E virus (HEV) transmission in South-East Asia was assessed from a review of 6 published and 3 unpublished NAMRU-2 reports of hepatitis outbreak investigations, cross-sectional prevalence studies, and hospital-based case-control studies. Findings from Indonesia and Viet Nam show epidemic foci centred in jungle, riverine environments. In contrast, few cases of acute, clinical hepatitis from cities in Indonesia, Viet Nam and Laos could be attributed to HEV. When communities in Indonesia were grouped into areas of low (< 40%), medium (40-60%), and high (> 60%) prevalence of anti-HEV antibodies, uses of river water for drinking and cooking, personal washing, and human excreta disposal were all significantly associated with high prevalence of infection. Conversely, boiling of river drinking water was negatively associated with higher prevalence (P < 0.01). The protective value of boiling river water was also shown in sporadic HEV transmission in Indonesia and in epidemic and sporadic spread in Viet Nam. Evidence from Indonesia indicated that the decreased dilution of HEV in river water due to unusually dry weather contributed to risk of epidemic HEV transmission. But river flooding conditions and contamination added to the risk of HEV infection in Viet Nam. These findings attest to a unique combination of ecological and environmental conditions predisposing to epidemic HEV spread in South-East Asia.

Blood samples were collected from 7572 healthy volunteer blood donors from 21 of the 27 Indonesian provinces, and tested for antibodies to hepatitis C virus (anti-HCV) using the new second-generation enzyme immunosorbent assay, and also tested for hepatitis B surface antigen (HBsAg). We detected anti-HCV in 2.1% of the blood donors. No statistically significant difference was found between males and females or between locations, but there was a statistically significant increasing likelihood of anti-HCV prevalence with increasing age. HBsAg was found in 8.8% of the 3839 tested donors. There was no statistically significant difference between sexes or age groups, but there was a statistically significant higher prevalence in the islands of Sulawesi and eastern Indonesia. Only 7 individuals, from 5 locations, were both anti-HCV and HBsAg positive. Based on responses to a questionnaire, a history of surgery, blood transfusion, intravenous medication, and acupuncture were identified as risk factors for the presence of anti-HCV. No such risk factor was identified for HBsAg prevalence. The combined data suggest separate modes of transmission for the 2 viruses, and indicate the need for continued surveillance for these agents in Indonesian blood banks.

Abstract.A study was conducted to describe the genetic diversity of hepatitis C virus (HCV) in a population of positive blood donors from throughout Indonesia. Repeat analysis by reverse transcription-polymerase chain reaction (RT-PCR) of 102 anti-HCV positive samples showed that 67 gave HCV-specific positive signals by the PCR for the 5Ј-untranslated genomic region of HCV. Further genotypic analysis on 64 HCV RNA-positive samples indicated that 57 belonged to the following individual genotypes: 1a, 1b, 2a, 2b, and 3b. The predominant HCV genotypes in this donor population were 1b (57.8 %), 2a (17.2 %), and 3b (10.9 %). The core sequences of the 4 indeterminate samples when aligned with published sequences of various HCV genotypes showed a range of homology from 16.16% to 78.67%. Comparative analysis of genotypic representation from other anti-HCV-positive study populations, including polytransfused pediatric and adult renal dialysis groups, is now being carried out to determine the potential genotypic association with mechanistic HCV spread.Ever since its molecular characterization in 1989, hepatitis C virus (HCV) has been shown to be the major cause of acute and chronic blood borne non-A non-B hepatitis and the leading cause of chronic liver disease worldwide (for a review see 1,[2][3][4] . This initial molecular characterization led to the use of genomic sequence information from reverse transcription-polymerase chain reaction (RT-PCR)-assisted amplified partial and/or full length HCV RNA on viral isolates as a means to classify these isolates into genetic groups, genotypes, and subtypes, and to the definition of primers, probes and first-and second-round PCR techniques to identify, group, and classify known and unknown isolates of HCVs worldwide. [5][6][7][8][9][10][11][12][13][14][15][16] An accumulation of such sequence information has led to the definition of HCV types, subtypes, and genetic groups. So far, 6 major HCV types and more than 74 different subtypes have been catalogued, and the number continues to grow as new isolates are sequenced and more countries are included in the sampling of HCV. However, whether genetic group, sub-type, and even type influence clinical outcome, response to therapy, and immune response remains to be established. Such sequence information and typing/subtyping data is nonetheless considered important for a number of reasons, some of which include the fact that such databases are critical to 1) the understanding of the global, regional and national epidemiology of HCV virus infection and transmission, 2) the design and evaluation of serologic assays, 3) the rational design of vaccine candidates against these isolates, 4) the study of the differences in the response of such HCV-infected patients to therapy with agents such as interferon-alpha, 17,18 and 5) the study of the diverse clinical outcomes associated with such diverse viruses. The clinical outcome of HCV infection is markedly variable ranging form subclinical, self-limiting infection to end-stage liver disease with...

No abstract