ABSTRACT
We conducted seroepidemiological studies on antibody prevalence to hepatitis E virus (HEV) in 5,233 sera from 11 countries to ascertain the present state of HEV infection on a global basis. The prevalence of anti-HEV IgG increased with age in these tested countries, but the rate of antibody positivity was over 20% in the 16-30 year-old group in most of the participating countries, except for Japan, the USA, and Spain. Of patients with acute hepatitis of unknown etiology from Nepal, 56% (14/25) were positive for the IgM class of anti-HEV antibody. In addition, HEV RNAs in the serum from 3 Nepali patients who had the IgM antibody were detected by nested PCR and all of the HEV genes isolated belonged to genotype 1. Our results indicate that HEV is spreading worldwide, not only in developing countries, but also in more industrialized countries than previously thought.
Subject(s)
Global Health , Hepatitis E/epidemiology , International Cooperation , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Asia/epidemiology , Bolivia/epidemiology , Child , Child, Preschool , Egypt/epidemiology , Europe/epidemiology , Female , Health Surveys , Hepatitis Antibodies/blood , Humans , Infant , Infant, Newborn , Male , Middle Aged , Seroepidemiologic Studies , United States/epidemiologyABSTRACT
In Asia, genotypes B and C are the most common genotypes of hepatitis B virus (HBV); and genotype C causes more severe liver disease. Core promoter/precore (CP/PC) mutants, known to be linked to these genotypes, could have an impact on the progression and severity of liver disease. Sera of 115 patients, including 39 acute and 76 chronic Vietnamese HBV infected patients, were tested for their liver profile, HBeAg, HBV genotypes, and HBV DNA level. Fragments of 282 nucleotides covering CP/PC were amplified, sequenced, and analysed. In the acute group, CP/PC mutants accounted for 38.4 and 25.6%, respectively. Genotype B was found to be predominant (74.3%, P < 0.05) and linked to the PC mutant (A1896) (P < 0.05). In the chronic group, CP/PC mutants accounted for 61.7 and 32.8%. CP mutants, especially the T1762/A1764 double mutant, were found to correlate with genotype C (81%, P < 0.001), liver cirrhosis, and hepatocellular carcinoma (P < 0.05). Therefore, genotype C in Vietnam, which carried high rate of C-1858 (70%), could play an important role in causing severe chronic liver disease.
Subject(s)
Codon, Terminator , Hepatitis B Core Antigens/genetics , Hepatitis B virus/classification , Mutation , Promoter Regions, Genetic , Protein Precursors/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Base Sequence , Female , Genotype , Hepatitis B/virology , Hepatitis B virus/genetics , Hepatitis B virus/pathogenicity , Hepatitis B, Chronic/physiopathology , Hepatitis B, Chronic/virology , Humans , Male , Middle Aged , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA , VietnamABSTRACT
A genomic characterization of hepatitis B virus (HBV) was done for 56 pre-S1/pre-S2 genes and 10 full-length HBV genotype C isolates from five Asian countries. Phylogenetic analysis of the pre-S1/pre-S2 genes revealed two major groups within genotype C: one for isolates from southeast Asia including Vietnam, Myanmar and Thailand (named HBV/C1) and the other for isolates from Far East Asia including Japan, Korea and China (named HBV/C2). This finding was confirmed by phylogenetic analysis based on the full-length sequence of 32 HBV genotype C isolates, including 22 from database entries. Two isolates from Okinawa, the island off the southern end of Japan, formed a different branch. Specific amino acid sequence changes were identified in the large S protein (amino acids 51, 54, 60, 62 and 73) and P protein (amino acids 231, 233, 236, 248, 252 and 304). Our results indicate that genotype C of HBV can be classified into at least two subgroups.
Subject(s)
Hepatitis B virus/classification , Asia , Databases, Genetic , Gene Products, pol/genetics , Genes, Viral , Hepatitis B virus/genetics , Hepatitis B virus/isolation & purification , Humans , Molecular Sequence Data , Phylogeny , Viral Envelope Proteins/geneticsABSTRACT
A molecular epidemiological survey of various hepatitis viral infections, including hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV), was carried out in Ho Chi Minh City, Vietnam. This study included of 295 patients with liver disease (234 viral related and 61 non-viral related) and 100 healthy individuals. The infection rates of HBV and HCV in 234 liver disease patients with acute hepatitis, chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, were 31.2 and 19.2%, respectively. On the other hand, detection rates of these viruses in healthy populations were 10 and 2%, respectively (P<0.005 and <0.0001, respectively). None of cases tested was positive for HDV RNA. The most common viral genotypes were type B and C of HBV (43 and 57%) and type 2a of HCV (33.3%). Surprisingly, high prevalence of HBV pre-S2 deletion mutant was found in 22 of 87 (25.3%) patients with chronic liver disease. Moreover, antibody to hepatitis E virus (HEV) immunoglobulin G (IgG) was detected in 78 of 185 (42%) and IgM in 1 of 185 (0.5%) patients. The age prevalence of anti-HEV IgG was reached 61.9% in 21-40-year-olds. These results suggest that these hepatitis viruses, except for HDV, are spreading among liver disease patients in Ho Chi Minh city, Vietnam and HBV was the most important causative agent correlated with liver disease in this area.
