Contribution of HEV and HCV in causing fulminant non-A, non-B hepatitis in western India

The expression patterns of immune response genes in the Peripheral Blood Mononuclear cells of pregnant women presenting with subclinical or clinical HEV infection are different and trimester-dependent: A whole transcriptome analysis

Hepatitis E is an enteric disease highly prevalent in the developing countries. The basis for high mortality among pregnant hepatitis E patients remains unclear. Importantly, a large proportion of infected pregnant women present with subclinical infection as well. In order to understand the possible mechanisms influencing clinical presentation of hepatitis E in pregnant women, we explored a system biology approach. For this, PBMCs from various categories were subjected to RNAseq analysis. These included non-pregnant (NPR, acute and convalescent phases) and pregnant (PR, 2^nd and 3^rd trimesters, acute phase and subclinical HEV infections) patients and corresponding healthy controls. The current study deals with immune response genes.

In contrast to exclusive up-regulation of nonspecific, early immune response transcripts in the NPR patients, the PR patients exhibited broader and heightened expression of genes associated with innate as well as adaptive T and B cell responses. The study identified for the first time (1) inverse relationship of immunoglobulin (Ig) genes overexpression and (2) association of differential expression of S100 series genes with disease presentation. The data suggests possible involvement of TLR4 and NOD1 in pregnant patients and alpha defensins in all patient categories suggesting a role in protection. Induction of IFNγ gene was not detected during the acute phase irrespective of pregnancy. Association of response to vitamin D, transcripts related to NK/NKT and regulatory T cells during subclinical infection are noteworthy.

The data obtained here could be correlated with several studies reported earlier in hepatitis E patients suggesting utility of PBMCs as an alternate specimen. The extensive, informative data provided here for the first time should form basis for future studies that will help in understanding pathogenesis of fulminant hepatitis E.

Association of Toll-like receptor 4 polymorphism with hepatitis E virus-infected Indian patients

Hepatitis E infection caused by hepatitis E virus (HEV), a major public health concern in developing countries, is responsible for sporadic and epidemic acute viral hepatitis in adults. Pathogenesis of hepatitis E infection is poorly understood. Toll-like receptors (TLRs) are the key players of innate immunity recognize pathogen-associated molecular patterns (PAMPs). Previously, we found higher TLR4 expression (at protein and gene level) with impaired cytokine response upon stimulus of PBMCs with LPS in HEV-infected patients. In view of the earlier observations of the association of polymorphisms in TLR4 genes (A299G, C399T) with liver diseases, we investigated TLR4 polymorphisms in HEV-infected patients. We observed the significant association of TLR4-399CC and CT alleles with hepatitis E (both subclinical and acute patients). Carrier frequency of TLR4-399 CT was lower in patients' categories in comparison with the controls. Higher frequency of allele TLR4-399C significantly correlated with disease progression. Acute hepatitis E patients showed the higher frequency of CG and TA haplotypes, while the rare haplotype (TG) was more frequent in controls. The other single nucleotide polymorphism (SNP) at TLR4-299 (A>G) did not show any difference. We report here for the first time the association of TLR4 polymorphism with hepatitis E and suggest that TLR 4 hyporesponsiveness during HEV infection might be related to its polymorphism.

Seroprevalence, risk factors and genotype distribution for Hepatitis C infection: A study from rural hospital in Maharashtra

BACKGROUND AND OBJECTIVES

Hepatitis C is global health problem affecting a significant portion of the world's population. Available data in Western Maharashtra on seroprevalence, risk factors and genotype distribution are very limited.

OBJECTIVES

The present study was carried out to estimate the seroprevalence, factors influencing transmission and distribution of genotype of hepatitis C virus (HCV) in a hospital-based population.

MATERIALS AND METHODS

This was a cross-sectional, hospital-based study. A total of 25193 serum samples were tested for HCV and HBV infection. All samples from HCV antibody-positive patients were subjected for HCV RNA detection and genotype. Chi-square, unpaired t-test, logistic regression analysis was used for statistical analysis.

RESULTS

The seroprevalence for anti-HCV-Ab was 0.46%. Backward multivariate logistic regression analysis revealed increasing age; alcoholic, blood transfusion and dialysis were significant risk factors. Of 116 patients with HCV, 8 (6.89%) patients had HCV-HBV co-infection. The most common genotype (61.90%) was 3 followed by Genotype 1 (38.09%).

CONCLUSIONS

In the present study, significant risk factors were a history of blood transfusion, habit of alcohol, dialysis. The prevention of HCV infection can be achieved by screening of blood and blood products and creating awareness about risk factors. Since the efficacy of current and new therapies differ by genotype, genotype study is essential.

Differential Immune Responses in Mice Immunized with Recombinant Neutralizing Epitope Protein of Hepatitis E Virus Formulated with Liposome and Alum Adjuvants

In the developing countries, Hepatitis E virus (HEV) is a predominant cause of sporadic acute hepatitis in adults and waterborne epidemics leading to high mortality in pregnant women. Vaccine development mainly focuses on the structural capsid protein open-reading-frame-2 (ORF-2) of the virus. We successfully evaluated liposome-adjuvanted recombinant neutralizing epitope protein (rNEp), a part of ORF-2, 458-607aa, in mice and rhesus macaques. We compared immune response to adjuvants alone, rNEp alone, or adjuvanted with liposome (lipo-rNEp)/alum (al-rNEp) in mice following intramuscular administration of two doses of 5 μg each. IgG anti-HEV titers (enzyme-linked immunosorbent assay), immunophenotyping (flow cytometry, CD3(+)CD4(+), CD3(+)CD8(+), CD11c(+), CD11b(+), CD19(+) cells; costimulatory markers CD80, CD86, MHC-I, MHC-II, and early activation marker CD69), and levels of Th1/Th2 cytokines (IL-2/IFN-γ/IL-4/IL-5 and additionally IL-1β/IL-6/IL-10/TNF for early time points) were determined at early (4/12/24-h postdose-1) and later time points (2 weeks post-both doses). IgG anti-HEV titers were higher in the lipo-rNEp group than al-rNEp post-both doses (p < 0.05). At early time points, cell type proportions were comparable at the site of injection; IL-Iβ levels increased in lipo-rNEp, 24 h, while IL-6 levels rose in lipo-rNEp/al-rNEp/alum-alone groups, 4 h, compared to controls. In the draining lymph nodes (DLNs), CD11c(+)CD86(+) cells increased at 24 h in liposome-alone/lipo-rNEp groups. A rise in the CD11c(+)CD69(+) cells was noted in the lipo-rNEp group compared to other groups (p < 0.05). Cytokine levels in the spleen/sera remained unchanged in all the groups (p > 0.05). At 2 weeks postdose-2, CD11c(+)MHC-II(+)/CD11b(+)MHC-II(+) cells increased in the spleen in the lipo-rNEp and al-rNEp groups, respectively. In the DLNs, CD19(+)MHC-II(+) cells increased in rNEp/al-rNEp/lipo-rNEp groups post-both doses and CD11c(+)CD86(+) cells in the lipo-rNEp group. A balanced Th1/Th2 response was evident in the lipo-rNEp, while a Th2 bias was noted in al-rNEp. Different immune response gene clustering patterns were noted in uncultured spleens from immunized mice and cultured-stimulated splenocytes. In conclusion, lipo-rNEp is a better immunogen, works through dendritic cells, and elicits a balanced Th1/Th2 response, while alum functions through macrophages and induces a Th2 response.

Effect of pregnancy on anti-HEV antibody titres, plasma cytokines and the corresponding gene expression levels in the PBMCs of patients presenting with self-recovering clinical and subclinical hepatitis E

High mortality in pregnant women (PR) is a characteristic of hepatitis E in developing countries. To understand the pathogenesis of HEV infection in self-limiting disease during pregnancy, we compared clinical (PR-patients) and subclinical-HEV-infections in pregnant women in the first (SC-PR-1) and later (2nd and 3rd, SC-PR-2+3) trimesters with the respective healthy controls and acute non-PR patients. The SC-PR-2+3 exhibited lower ALT, bilirubin levels, anti-HEV-IgM/IgG titres than the acute-PR/non-PR-patients (p<0.05-0.0001). IFNγ/IL4ratios indicated Th2/Th1 bias in non-PR and PR-patients respectively. Raised levels of 10/20 plasma cytokines in the non-PR-patients reflect predominant inflammatory response, unaltered- IFNγ/reduced-IFNα responses and a robust chemokine secretion. On contrary, the acute-PR-patients exhibited drastic reduction in majority of the cytokines relative to in the non-PR-patients. Importantly, diminished or unaltered response was noted in the acute-PR-group when compared to the corresponding controls. The only exception was sIL2RA, increasing in both patient categories. Of the 14 genes evaluated, the expression of IFNγ/IL10/IL1A/IL7/CCL2/CCL3/CXCL8/CXCL10 was higher in the non-PR patients. Of these, the expression of IFNγ/IL10/IL1A/CCL2/CCL3/CXCL8 and, additionally, IL2/IL6/TNF genes was higher in the clinical-PRs. Almost identical pattern was noted in the control-PR-2+3 category indicating no influence of HEV infection. Comparison of patient-categories identified significant elevation of IFNγ(P<0.001), CCL2(p<0.01), CXCL8(P<0.05), IL1B(p<0.05) and IL10(P<0.0001) and decrease in CXCL10(<0.05) in the PR-patients. The results suggest antibody-dependent disease severity and impaired immune response in the PR patients. Higher expression of cytokine-genes in the PBMCs did not correlate with the plasma-cytokine levels in the PR-patients.

Analysis of helicase domain mutations in the hepatitis E virus derived from patients with fulminant hepatic failure: effects on enzymatic activities and virus replication

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Effect of fulminant hepatic failure (FHF) associated mutations on helicase activities and virus replication were checked.

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All the FHF mutants showed comparable unwinding activities with the wild type protein despite the differences in ATPase activities.

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All the FHF mutant replicons showed marginal decrease in virus replication compared to the wild type replicon suggesting alternate function/s of the helicase protein.

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Walker A motif and Walker B motif in the helicase domain are indispensable for HEV replication.

Fulminant hepatic failure (FHF) is the severe form of hepatitis E virus infection. Virus sequence analyses from severe cases have shown presence of unique and highly conserved mutations in the helicase domain of genotype 1, 3 and 4 viruses. We evaluated role of two amino acid replacements (L1110F) and (V1120I); found to be frequent in genotype 1 FHF-E viruses from India. Three mutant helicase proteins (two with single point mutations and one with dual mutations) were expressed in Escherichia coli and evaluated for their ATPase and RNA unwinding activities. Both L1110F and V1120I helicase mutants showed marginal decrease in ATPase activity, while L1110F/V1120I dual mutant showed normal ATPase activity. All three mutants proteins showed RNA unwinding activities comparable to wild type protein. Corresponding mutations were made in the helicase domain of HEV RLuc replicon and replication efficiencies were tested in the S10-3 (Huh 7) cells. The mutant replicon V1120I showed lower replication as compared to L1110F and L1110F/V1120I mutants. However, all three replicon mutants showed lower replication efficiencies as compared to the wild type replicon. Walker A and Walker B motif mutant HEV replicons were unable to replicate indicating essential role of the virus encoded helicase domain during HEV replication. FHF-E associated helicase mutations resulted in only marginal decrease in the virus replication suggesting alternate function/s of the helicase protein. Mutations in the helicase domain of FHF-E viruses may be responsible for changing virus or host-virus protein–protein interactions, causing alterations in the host responses, eventually leading to more severe disease manifestations.

Fatal outbreaks of jaundice in pregnancy and the epidemic history of hepatitis E

Space-time clustering of people who fall acutely ill with jaundice, then slip into coma and death, is an alarming phenomenon, more markedly so when the victims are mostly or exclusively pregnant. Documentation of the peculiar, fatal predisposition of pregnant women during outbreaks of jaundice identifies hepatitis E and enables construction of its epidemic history. Between the last decade of the 18th century and the early decades of the 20th century, hepatitis E-like outbreaks were reported mainly from Western Europe and several of its colonies. During the latter half of the 20th century, reports of these epidemics, including those that became serologically confirmed as hepatitis E, emanated from, first, the eastern and southern Mediterranean littoral and, thereafter, Southern and Central Asia, Eastern Europe, and the rest of Africa. The dispersal has been accompanied by a trend towards more frequent and larger-scale occurrences. Epidemic and endemic hepatitis E still beset people inhabiting Asia and Africa, especially pregnant women and their fetuses and infants. Their relief necessitates not only accelerated access to potable water and sanitation but also vaccination against hepatitis E.

Association of polymorphisms in the promoter regions of TNF-α (-308) with susceptibility to hepatitis E virus and TNF-α (-1031) and IFN-γ (+874) genes with clinical outcome of hepatitis E infection in India

BACKGROUND & AIMS

Hepatitis E virus (HEV) is the predominant cause of acute viral hepatitis (AVH-E) and acute liver failure (ALF-E) among adults from developing countries. Pathogenesis of hepatitis E is poorly understood. Earlier, we showed association of elevated serum levels of TNF-α, IFN-γ, and IL-12 with ALF-E. The role of TNF-α and IFN-γ gene promoter polymorphisms with disease severity was investigated.

METHODS

The study population included 374 anti-HEV negative apparently healthy controls, 136 subclinical hepatitis E, 353 AVH-E, and 25 ALF-E patients. Polymorphisms at promoter regions of TNF-α-308G/A, TNF-α-1031T/C, and IFN-γ+874T/A were investigated employing allelic discrimination/SNaPshot™ methods.

RESULTS

ALF-E patients were younger with significantly higher ALT levels when compared to other categories. Genotype TNF-α-308AA frequency was significantly higher among subclinical and clinical hepatitis E than the controls (p=0.03, 0.0007). No significant difference was observed among AVH-E/ALF-E groups. The -308A allele was significantly higher in HEV-infected individuals; fatal ALF patients showed higher frequency than the recovered (p=0.024). TNF-α-1031CC, IFN-γ+874TT, and IFN-γ+874TA genotypes were significantly associated with clinical disease. With respect to the controls, genotype+874TA was more frequent in subclinical infection (p=0.005) while+874AA frequency was lower in the AVH-E category (p=0.003).

CONCLUSIONS

The data reveal association of TNF-α-308AA genotype with susceptibility to HEV and that of TNF-α-1031CC and IFN-γ+874TT and TA with clinical disease, irrespective of the outcome. Higher -308A allele frequency was associated with susceptibility to HEV and the fatal outcome of ALF-E.

Epidemic of hepatitis B with high mortality in India: association of fulminant disease with lack of CCL4 and natural killer T cells

An explosive outbreak of Hepatitis B with high mortality was reported in 2009, in Modasa, Gujarat, India. Mortality was associated with basal core promoter and precore mutant hepatitis B virus (HBV). The current study addresses the role of immunological parameters in the progression to fulminant hepatitis. The study population comprised of 22 acute HBV patients, 13 fulminant HBV liver failure patients and 54 healthy controls. Hepatitis B surface antigen-induced CTL responses by enzyme-linked immunosorbent spot (ELISPOT), cytokine and chemokine quantitation by Bioplex assay, peripheral NK, natural killer T (NKT), CD4 and CD8 T-cell frequencies by flow cytometry were carried out. The median percentage of NK cells in the lymphocytes of the acute and fulminant liver failure patients were significantly lower compared to controls. Acute and fulminant liver failure patients had significantly high and comparable NKT cells compared to controls, respectively. Importantly, NKT cells were significantly lower in fulminant HBV liver failure than acute HBV patients. Circulating peripheral CD4/CD8 T-cell subsets among the patient categories and controls were comparable. In acute HBV patients, a significant increase in IFN-γ release was recorded (ELISPOT) by the unstimulated, antigen-stimulated and mitogen-stimulated cells when compared to controls. Comparisons of cytokines and chemokines among the disease categories revealed significantly lower levels of CCL4 in fulminant liver failure patients. NKT cells and CCL4 might be playing a pivotal role in limiting HBV infection among the patients investigated.

An outbreak of hepatitis B with high mortality in India: association with precore, basal core promoter mutants and improperly sterilized syringes

In 2009, an outbreak of hepatitis B with high mortality was observed in Sabarkantha district, Gujarat state, India with 456 cases and 89 deaths. Hospitalized patients with self-limiting disease (152, AVH)) and fulminant hepatic failure (39, FHF including 27 fatal and 12 survivals) were investigated. These were screened for diagnostic markers for hepatitis viruses, hepatitis B virus (HBV) genotyping and mutant analysis. Complete HBV genomes from 22 FHF and 17 AVH cases were sequenced. Serosurveys were carried out in the most and least affected blocks for the prevalence of HBV and identification of mutants. History of injection from a physician was associated with FHF and AVH cases. Co-infection with other hepatitis viruses or higher HBV DNA load was not responsible for mortality. Four blocks contributed to 85.7% (391/456) of the cases and 95.5% (85/89) mortality while two adjacent blocks had negligible mortality. Sequence analysis showed the presence of pre-core and basal core promoter mutants and 4 amino acid substitutions exclusively among FHF cases. None of the self-limiting patients exhibited these dual mutations. Genotype D was predominant, D1 being present in all FHF cases while D2 was most prevalent in AVH cases. Probably due to violation of accepted infection control procedures by the qualified medical practitioners, HBV prevalence was higher in the affected blocks before the outbreak. Gross and continued use of HBV contaminated (mutant and wild viruses) injection devices led to an explosive outbreak with high mortality with a striking association with pre-C/BCP mutants and D1 genotype.

Acute viral hepatitis morbidity and mortality associated with hepatitis E virus infection: Uzbekistan surveillance data

Background

In Uzbekistan, routine serologic testing has not been available to differentiate etiologies of acute viral hepatitis (AVH). To determine the age groups most affected by hepatitis E virus (HEV) during documented AVH epidemics, trends in AVH-associated mortality rate (MR) per 100,000 over a 15-year period and reported incidence of AVH over a 35-year period were examined.

Methods

Reported AVH incidence data from 1971 to 2005 and AVH-associated mortality data from 1981 to 1995 were examined. Serologic markers for infection with hepatitis viruses A, B, D, and E were determined from a sample of hospitalized patients with AVH from an epidemic period (1987) and from a sample of pregnant women with AVH from a non-epidemic period (1992).

Results

Two multi-year AVH outbreaks were identified: one during 1975–1976, and one during 1985–1987. During 1985–1987, AVH-associated MRs were 12.3–17.8 per 100,000 for the general population. Highest AVH-associated MRs occurred among children in the first 3 years of life (40–190 per 100,000) and among women aged 20–29 (15–21 per 100,000). During 1988–1995 when reported AVH morbidity was much lower in the general population, AVH-associated MRs were markedly lower among these same age groups. In 1988, AVH-associated MRs were higher in rural (21 per 100,000) than in urban (8 per 100,000) populations (RR 2.6; 95% CI 1.16–5.93; p < 0.05). Serologic evidence of acute HEV infection was found in 280 of 396 (71%) patients with AVH in 1987 and 12 of 99 (12%) pregnant patients with AVH in 1992.

Conclusion

In the absence of the availability of confirmatory testing, inferences regarding probable hepatitis epidemic etiologies can sometimes be made using surveillance data, comparing AVH incidence with AVH-associated mortality with an eye to population-based viral hepatitis control measures. Data presented here implicate HEV as the probable etiology of high mortality observed in pregnant women and in children less than 3 years of age in Uzbekistan during 1985–1987. High mortality among pregnant women but not among children less than 3 years has been observed in previous descriptions of epidemic hepatitis E. The high mortality among younger children observed in an AVH outbreak associated with hepatitis E merits corroboration in future outbreaks.

Challenge studies in Rhesus monkeys immunized with candidate hepatitis E vaccines: DNA, DNA-prime-protein-boost and DNA-protein encapsulated in liposomes

Complete ORF2 gene (1983bp) of hepatitis E virus (HEV) and the 450bp region within ORF2 containing neutralizing epitope (NE) cloned in pVAX1 and corresponding proteins expressed in baculovirus and prokaryotic systems respectively were evaluated as vaccine candidates. Two doses of liposome encapsulated DNA plus corresponding protein with both ORF2 and NE regions (Lipo-ORF2-DP and Lipo-NE-DP) showed 100% seroconversion and comparable anti-HEV titres in Swiss albino mice. These vaccine candidates were further evaluated as DNA, DNA-prime-protein-boost (DPPB) and liposome formulations in Rhesus monkeys. Monkeys receiving ORF2/NE DNA seroconverted after fourth dose while those immunized employing ORF2-DPPB format seroconverted at 7 weeks post third dose. In view of the delayed weak antibody response, these monkeys were not challenged. Though Lipo-ORF2-DP was immunogenic, 2 of the 4 monkeys developed HEV infection following homologous virus challenge of 100 Monkey Infectious Dose(50). Both monkeys immunized with Lipo-NE-DP and 1 of the 2 monkeys immunized with NE-DPPB showed complete protection, the second monkey being protected from hepatitis with limited viral replication. Irrespective of the type of immunogen, all challenged monkeys were protected from hepatitis. The results document Lipo-NE-DP to be a promising vaccine candidate needing further evaluation.

Immunogenicity of candidate hepatitis E virus DNA vaccine expressing complete and truncated ORF2 in mice

Hepatitis E virus (HEV) is a major cause of enterically transmitted acute hepatitis of adults in developing nations. Our present studies show that, the complete ORF2 gene (1-660 amino acids, a.a.) coding for capsid protein of HEV as candidate DNA vaccine induced significant specific humoral and cellular immune responses in mice. Gene gun based DNA administration led to higher seroconversion rates and HEV-specific antibody titers as against needle-injection method. The region (458-607a.a.) within ORF2 protein is reported to harbour the predominant neutralization epitope/s (NE) of HEV. The NE DNA also induced HEV-specific immune responses in mice. NE-based DNA-prime-protein boost approach was observed to be superior to NE DNA based approach. Co-administration of plasmid expressing mouse granulocyte macrophage colony stimulating factor (GM-CSF) induced immune response at similar level as that with ORF2/NE plasmid alone. IgG1 was the predominant isotype irrespective of the approach used. HEV-specific antibodies in seroconverted mice sera could bind/neutralize HEV in an in vitro ELISA-based assay. In conclusion, efficacy of ORF2 and NE based DNA/DNA-prime-protein-boost approaches are worth exploring in monkey model.

Aetiology and prognostic factors in acute liver failure in India

The early prognostic indicators for acute liver failure in endemic zones for hepatitis E virus have not been determined. All consecutive patients with acute liver failure from a geographically defined region endemic for hepatitis E virus were studied over the period April 1989-April 1996. Demographic, clinical and biochemical parameters were recorded at presentation and serum samples were analysed for known viral hepatitis (A-E) markers. Multiple parameters were compared in survivors and non-survivors in a univariate analysis. All significant factors on univariate analysis were entered into a stepwise logistic regression analysis to identify independent variables of prognosis. The sensitivity and specificity of significant prognostic factors was then assessed. A total of 180 [69 males and 111 females: age (mean +/- SD) 31.1 +/- 14.7 years] with acute liver failure were studied. Of these, 131 (72.8%) patients died. Hepatitis E virus was the aetiological cause in 79 (43.9%) patients, while hepatitis A virus, hepatitis B virus, hepatitis C virus and non-A, non-E agent/'s could be incriminated in four (2.1%), 25 (13.9%), 13 (7.2%) and 56 (31.1%) patients respectively. Of 83 women in childbearing age, 49 (59.0%) were pregnant, 33 (67.3%) of these were in the third trimester. Forty-seven (95.8%) pregnant women had HEV infection. Nine variables differed significantly between survivors and non-survivors on univariate analysis. Of these, four variables which predicted the adverse outcome on multivariate analysis were non-hepatitis-E aetiology, prothrombin time >30 s, grade of coma >2 and age >40 years in that order of significance. Pregnancy per se or duration of gestation did not adversely affect the prognosis. In endemic areas, hepatitis E virus is the commonest cause of acute liver failure. Acute liver failure occurs in a high proportion of pregnant women, mostly in third trimester. Early predictors of a poor outcome are non-E aetiology, prothrombin time >30 s, grade of coma >2 and age >40 years.

Changing scenario of hepatitis A virus and hepatitis E virus exposure among the primitive tribes of Andaman and Nicobar Islands, India over the 10-year period 1989-99

The Andaman and Nicobar Islands, Union Territory of India, are home to six primitive tribes. Studies carried out earlier among these tribes revealed very high rates of hepatitis B infection. We have now studied hepatitis A and E infection among them. A total of 951 serum samples were collected from four accessible tribes (Nicobarese, Shompens, Onges and Great Andamanese) and tested for antibodies against hepatitis A and E viruses. In addition, 240 serum samples collected a decade earlier from age-stratified Nicobarese were also screened. Hepatitis A virus (HAV) infection was found to be highly endemic among all the tribes, whereas hepatitis E virus (HEV) infection was common among the Nicobarese and Shompens. The age group-wise prevalence of these infections among the Nicobarese showed different patterns, HAV prevalence rising significantly from those aged 10 years and thereafter reaching a plateau, whereas HEV prevalence was found to be more evenly distributed over all age groups, but rising somewhat after 30 years of age. Over the last decade, the prevalence of HAV among the Nicobarese has declined slightly, particularly in those aged 10 years or less whereas HEV infection has more than doubled over all age ranges. Different HEV prevalence observed among the tribes could not be attributed to differences in sanitation or water supply. This fact and the different age-wise patterns of HAV and HEV prevalences is suggestive of different modes of transmission of HEV that are not shared. The highest rates for HEV were among those tribes which reared pigs suggesting that pigs might serve as reservoir of HEV. Further studies are needed, however, to validate these findings.

Changing epidemiology of hepatitis A and hepatitis E in urban and rural India (1982-98)

The epidemiology of hepatitis A virus (HAV) and hepatitis E virus (HEV) was assessed among age-stratified urban high socioeconomic, lower middle socioeconomic status and rural populations from western India in 1998. When compared with previous surveys, a clear shift from high to intermediate endemicity of HAV was evident only for higher socioeconomic population (1982-98), raising the possibility of outbreaks of hepatitis A in this category. A decrease in anti-HAV positivity was noted in rural children aged 6-10 years. Lower circulation of HEV was noted among < 25-year-old urban higher socioeconomic and rural individuals. For both viruses, the lower middle socioeconomic populations were comparable in 1982 and 1998. Socioeconomic status and family size (odds ratio = 23 and 1.6, respectively) were independently associated with anti-HAV positivity. Age, lower middle socioeconomic status and well water were significant independent variables for HEV infection (odds ratio = 5.7, 2.4 and 1.9, respectively). Hence, vaccination policy for hepatitis A needs to be reviewed.

Prevalence of anti-hepatitis E virus antibodies in different Indian animal species

Prevalence of IgG antibodies to hepatitis E virus (IgG-anti-HEV) was determined among different animal species from India. Seropositivity varied from 4.4% to 6.9% in cattle, 54.6-74.4% in pigs and 2.1-21.5% in rodents. Of the 44 dogs screened, 10 were positive (22.7%). None of the 250 goat sera tested were found to be anti-HEV positive. Among rodents, over 50% serum samples collected in 1985 from Bandicota bengalensis were positive for anti-HEV antibodies. No evidence of HEV infection was obtained following experimental inoculation of an Indian strain (AKL-90) of HEV into anti-HEV negative pigs and goats. The results document varied prevalence of anti-HEV antibodies in different animal species from India and of inability of Indian pigs and goats to support replication of at least one human strain of HEV.

HAV and HEV infection in hospitalised hepatitis patients in Alexandria, Egypt

A total of 202 serum and stool samples from acute hepatitis patients attending the Fever Hospital of Alexandria, Egypt, have been studied to reveal markers of hepatitis virus infection. Anti-HAV IgM were detected in 21 out of 202 sera (10.4%), whereas 201 sera (99.5%) had anti-HAV IgG. The first age attack was in the class-age 0-9 years with 64.7% of anti-HAV IgM positive sera. Among 202 patients, anti-hepatitis E IgG (sample/over cut off > 1.0) was identified in 90 patients (44.5%). The anti-HEV seropositivity ranged from 17.6% to 60.0% in the different age groups, with the highest level in the class-age 20 29 years. Anti-hepatitis E IgM were identified in 49 patients with the first age attack in the class-age 10-19 years (39.4%). HAV RNA was identified by nested PCR in 7 samples out of 15, whereas HEV RNA was present in 4 out of 75 stool samples. Direct DNA sequence of the latter PCR products confirmed the presence of the HEV genome; comparison of the sequences of the isolates from Egypt with those in data banks revealed the highest homology to the Burma strain. Our data confirm that HAV and HEV are common causes of acute sporadic hepatitis in Alexandria but with different peak age positivity. Occasionally, but not infrequently, dual infections (HAV-HEV and HEV-enteric viruses) were also found. The risk analysis indicates that patients living in rural areas are exposed to a higher risk of hepatitis E infection compared to the urban population, whereas the presence of anti-HEV IgG was significantly associated with consumption of common village water and use of indoor dry pit and oral therapy for schistosomiasis.

Acute sporadic non-A, non-B hepatitis in Northeastern Brazil: etiology and natural history

In a 4-year follow-up study, patients with acute sporadic non-A, non-B (NANB) hepatitis were evaluated to determine the etiology and natural history of the disease. Acute hepatitis C virus (HCV) was detected in 13 of 43 (30%) of patients, anti-hepatitis E virus (HEV) IgG in 5 (12%), and 25 (58%) were considered non-A-E. The HCV RNA was detected in all HCV patients but none of the non-A-E cases. The initial clinical and biochemical presentation of the HCV and non-A-E cases was quite similar, although 2 of the non-A-E patients had severe disease. The 5 patients who were found to be anti-HEV IgG-reactive recovered within 6 months of follow-up. Of the 13 HCV cases, alanine transaminase (ALT) levels returned to normal in 7 (53. 8%), while 6 (46.2%) continued to show abnormal ALT after 6 months of follow-up. However, 9 (69.2%) of them remained HCV-RNA-positive, denoting virological/biochemical dissociation. Long-term follow-up showed a reappearance of HCV RNA in 2 of the 4 patients who were in virological remission performing 84% of chronicity rate. Acute non-A-E hepatitis patients were less likely to evolve toward chronicity, as compared with acute HCV cases (16% vs. 84%; P =.0001). Only 4 (16%) of the non-A-E patients were hepatitis G virus (HGV)-RNA-positive. Concerning risk factors for acquiring parenterally transmitted viruses, tattooing was the only one that could be associated with HCV transmission (P =.002). No risk factors could be identified for putative non-A-E virus transmission. Liver biopsies performed for chronic HCV patients showed a variable degree of inflammation, while the non-A-E patients presented less severe histological disease.

Hepatitis E virus: can it be transmitted parenterally?

Of 200 voluntary blood donors screened for hepatitis E virus (HEV) RNA, employing the reverse transcription-polymerase chain reaction (RT-PCR), three were found to be positive (1.5%). None of the HEV RNA-positive blood donors had any symptoms at the time of blood donation or during subsequent follow-up. One donor was positive for immunoglobulin M (IgM) antibodies to HEV, with a raised serum alanine aminotransferase (ALT) level, whereas the other two donors were negative for both immunoglobulin G (IgG) and IgM antibodies to HEV. Follow-up blood samples collected 2-5 months later from HEV RNA-positive blood donors demonstrated the presence of IgG anti-HEV antibodies. Overall seroprevalence of IgG anti-HEV was 18.6%. Retrospective studies on samples collected from commercial blood donors and haemophiliacs revealed IgG anti-HEV positivity to be 24. 6% (46/191) and 24.4% (22/90) and statistically not different (P>0. 1) from the prevalence among voluntary blood donors and an age-matched normal population, respectively. However, a highly significant proportion of the paid plasma donors, with a high prevalence of IgG antibodies to human immunodeficiency virus and hepatitis C virus, were positive for IgG antibodies to HEV (54/71, 76%, P<0.001), indicating a possible role of blood-derived HEV in the transmission of the virus among plasma donors. These results demonstrate the possible risk of transfusion-associated hepatitis E in hyperendemic areas.

Long-term serological follow up and cross-challenge studies in rhesus monkeys experimentally infected with hepatitis E virus

BACKGROUND/AIMS

The aims of this study were to examine the decline of IgG anti-HEV antibodies over a period of 7 years in rhesus monkeys experimentally infected with hepatitis E virus, and to assess the protectivity of these antibodies by challenging the monkeys with a heterologous isolate of hepatitis E virus, 5 years after the primary inoculation.

METHODS

Nine rhesus monkeys (six non-pregnant and three pregnant at the time of hepatitis E virus inoculation) were followed serologically and biochemically for 7 years post-inoculation. Based on regression analysis, estimated time for IgG anti-HEV titers to reach 1:100 or 1:50 was calculated. Three of the monkeys inoculated initially with AKL-90 isolate and challenged 2 years later with PUN-85 isolate of hepatitis E virus were rechallenged with KOL-91 isolate of the virus, 5 years post-primary inoculation. Evidence of viral replication was assessed by measuring serum alanine aminotransferase levels, excretion of the virus in feces or bile (reverse-transcription polymerase chain reaction) and rise in IgG anti-HEV titers (ELISA).

RESULTS

None of the challenged monkeys showed evidence of disease. In contrast to extensive replication of the virus in anti-HEV-negative control monkeys, limited replication was noted in one of the challenged monkeys. The estimated time for the titers to reach 1:100 or 1:50 varied from 3.15 to 44.9 years (19.4+/-11.6 years) and 6.9 to 84.3 years (35.4+/-21.3 years), respectively. Decline in titers was independent of the pregnancy status at the time of infection or reexposure of the monkeys to HEV CONCLUSION: The results show persistence of IgG anti-HEV antibodies for a long time and protectivity of low titered antibodies against reinfection, leading to disease even after intravenous exposure to a heterologous isolate of hepatitis E virus.

Role of immune serum globulins in pregnant women during an epidemic of hepatitis E

The efficacy of an Indian preparation of immune serum globulins (ISG) was evaluated among pregnant women during an epidemic of hepatitis E in Karad, Western India from January to March 1993. Ten of 55 women receiving ISG developed immunoglobulin M (IgM) antibodies to hepatitis E virus (anti-HEV) during the 1 month of follow-up compared with 18 out of 53 control subjects. Although the total number of recent HEV infections was significantly less in the ISG-treated group, no significant difference could be shown in the proportion of clinical hepatitis E cases because of the very small numbers of patients who developed clinical disease. The observed marginal beneficial effect of ISG might be the result of a low immunoglobulin G (IgG) anti-HEV IgG titre (1:500) of the ISG preparation used. Preparation and testing of high-titred ISG should be a high priority for protecting pregnant women during epidemics of hepatitis E.

Clinical manifestations of hepatitis C

Hepatitis C is a common cause of viral hepatitis that progresses to chronic infection in the majority of patients. Clinically, the infection is generally asymptomatic, but it may present with a wide variety of symptoms. Cirrhosis, hepatocellular carcinoma, cryoglobulinemia, auto-antibodies, and glomerulonephritis have been strongly associated with HCV. There is a probable association with autoimmune disease and NHL. More information is needed to determine whether lichen planus, PCT, and other disorders are part of the growing clinical spectrum or just coincidental associations with chronic liver disease.