Home About us Contact
|
Home About us Contact | ||
|
|
||
Hepatitis A Virus (hepatitis a + virus)
Terms modified by Hepatitis A Virus Selected AbstractsSynthesis of Pseudoxazolones and Their Inhibition of the 3C Cysteine Proteinases from Hepatitis A Virus and Human Rhinovirus-14.CHEMINFORM, Issue 39 2002Yeeman K. Ramtohul Abstract For Abstract see ChemInform Abstract in Full Text. [source] Molecular epidemiology of hepatitis A virus in a group of Portuguese citizens living in Lisbon areaJOURNAL OF MEDICAL VIROLOGY, Issue 5 2007L. Rodrigues Abstract Hepatitis A virus (HAV) is the most important cause of acute infectious hepatitis worldwide. In Portugal, due to improvements in sanitation epidemic outbreaks of HAV infection have become less frequent. This report is the first, to our knowledge that characterized HAV in Portugal. For the detection and molecular characterization of HAV cases in a group of Portuguese individuals in the Lisbon area, 31 serum samples were tested: 8 from symptomatic children from an acute hepatitis A outbreak in a Roma (Gipsies) community (2004,2005), and 22 from patients with acute HAV from sporadic cases (2005,2006). A sample of CSF involved in a case of meningitis was also included. IgM anti-HAV detection and nested reverse transcription (RT-PCR), with primers located at the VP1-P2a region, was undertaken to detect HAV genome. In positive samples, molecular characterization was followed by phylogenetic analysis. All samples (n,=,31) were positive for IgM anti-HAV. HAV RNA was found in 96.7% of cases. All isolates were classified as genotype I: 22 belonged to sub-genotype IA (73.3%), and 8 to sub-genotype IB (26.7%). All strains obtained from an acute HAV outbreak had sub-genotype IA, in which seven isolates (87.5%) had identical sequences. In HAV sporadic cases sub-genotypes IA and IB were identified, and this may reflect the co-circulation of these two sub-genotypes in Portugal. Molecular epidemiology of HAV infection in this group of Portuguese appears to be similar to other European countries. HAV phylogenetic studies can provide important information for the design of appropriate public health measures. J. Med. Virol. 79:483,487, 2007. © 2007 Wiley-Liss, Inc. [source] Co-circulation of genotype IA and new variant IB hepatitis A virus in outbreaks of acute hepatitis in Hungary,2003/2004JOURNAL OF MEDICAL VIROLOGY, Issue 11 2006Gábor Reuter Abstract Hepatitis A virus (HAV) is one of the most important causes of acute infectious hepatitis worldwide. In Hungary, the reported number of HAV infections has been decreasing in the last four decades, nevertheless, still, each year 500,800 new cases and multiple outbreaks occur, particularly in the northeast region of Hungary. In Hungary, serology is used routinely to establish the diagnosis of HAV infection without genetic analysis of HAV strains for molecular epidemiology. In this study, serum samples collected from symptomatic patients were tested by enzyme-immunoassay (anti-HAV-IgM ELISA) to establish the cause of three acute hepatitis A outbreaks (outbreak 1,from low prevalence region in Southwest Hungary in 2003 and outbreaks 2 and 3 from the endemic region in Northeast Hungary in 2004). Outbreak strains were characterized by reverse transcription-polymerase chain reaction (RT-PCR) amplification of a 360 bp viral VP1/2A region, amplicon sequencing and phylogenetic analysis. Four, seven, and three sera from outbreaks 1, 2, and 3, respectively, were investigated by RT-PCR for HAV genome and HAV RNA was detected in 4 (100%), 4 (57%), and 2 (67%) samples. All strains belonged to genotype I HAV. Outbreak 1 was caused by the new variant subtype IB and outbreaks 2 and 3 caused by genetically identical subtype IA strains. The Hungarian IA and IB hepatitis A viruses had the highest nucleotide identity, 98.4% and 99.0%, to IT-SCH-00 and IT-MAR-02 strains, respectively, detected in year 2000 and 2002 in Italy. Endemic subtype IA and probably imported new variant subtype IB HAV viruses was detected in outbreaks of hepatitis in Hungary that are closely related genetically to HAV strains in Italy. J. Med. Virol. 78:1392,1397, 2006. © 2006 Wiley-Liss, Inc. [source] Sequential changes in hepatitis A virus genotype distribution in Estonia during 1994 to 2001JOURNAL OF MEDICAL VIROLOGY, Issue 2 2003Tatjana Tallo Abstract Hepatitis A virus (HAV) isolates from a large outbreak and from non-outbreak cases in Estonia were characterized by sequencing the aminoterminal VP1 region. From January 1998 to December 1999, a total of 1,084 cases of hepatitis A were reported to the Harjumaa-Tallinn and Ida-Virumaa Health Protection Services in Estonia. The attack rate was highest among males aged 15,29. Initial cases were noted to be associated with injecting drug use. IgM anti-HAV positive sera were available from 107 hospitalized outbreak cases and from 68 patients sampled during 1994 to 2001. HAV RNA was detected in 42% of sera from 1994,1996 and in 88% of sera from 1998,2001. It was possible to obtain HAV sequences from 83 outbreak and 29 background cases. The outbreak strain was represented by five different sequences, all belonging to subtype IIIA. During the outbreak, this IIIA strain also spread into the general population. All available non-outbreak isolates from 1994 to 2001 but one belonged to genotype IA and formed distinct clusters as compared to isolates from other parts of the world. One subtype IIIA isolate from 1995 was unrelated to the outbreak strain. Subtype IA had been dominating in Estonia during 1994,2001, but the outbreak strain from 1998 to 1999 was IIIA. This subtype was encountered previously in addicts in Sweden during the 1980s and in Norway at the end of the 1990s. This study supports the use of limited sequencing within the aminoterminal VP1 region for studying the molecular epidemiology of hepatitis A. J. Med. Virol. 70: 187,193, 2003. © 2003 Wiley-Liss, Inc. [source] Characterization of hepatitis A virus isolates from subgenotypes IA and IB in Rio de Janeiro, Brazil,JOURNAL OF MEDICAL VIROLOGY, Issue 1 2002Vanessa S. de Paula Abstract Hepatitis A virus (HAV) isolates from around the world have been classified into seven genotypes (I,VII). Most human strains belong to genotype I, which has been divided into two subgenotypes, A and B. South America has provided a small number of strains studied at the genome level. In the present study, IgM anti-HAV antibodies were detected in 116 out of 250 (46%) serum samples collected from consecutive patients with acute hepatitis referred to the Brazilian Reference Center for Viral Hepatitis, Rio de Janeiro. Viral RNA were extracted from all 250 samples and submitted to a reverse transcription-polymerase chain reaction (RT-PCR) assay designed to amplify a genome segment in the VP1/2A junction region. HAV RNA was detected in 54/116 (47%) and 17/134 (13%) IgM anti-HAV-positive and -negative sera, respectively. In addition, HAV RNA was detected in 17/35 (49%) IgM anti-HAV-positive sera that had been collected at a day care center where cases of acute hepatitis were being observed for 3 months. Nucleotide sequences (168 bp) of PCR products were determined for 30 HAV isolates. Phylogenetic analysis showed that 21 belonged to subgenotype IB, while 9 were of subgenotype IA. Interestingly, a concomitant circulation of isolates from subgenotypes IA and IB was observed in the day care center. J. Med. Virol. 66:22,27, 2002. © 2002 Wiley-Liss, Inc. [source] Hepatitis A virus (HAV) proteinase 3C inhibits HAV IRES-dependent translation and cleaves the polypyrimidine tract-binding proteinJOURNAL OF VIRAL HEPATITIS, Issue 9 2010T. Kanda Summary., Hepatitis A virus (HAV) infection is still an important issue worldwide. A distinct set of viruses encode proteins that enhance viral cap-independent translation initiation driven by an internal ribosome entry site (IRES) and suppress cap-dependent host translation. Unlike cytolytic picornaviruses, replication of HAV does not cause host cell shut off, and it has been questioned whether HAV proteins interfere with its own and/or host translation. HAV proteins were coexpressed in Huh-7 cells with reporter genes whose translation was initiated by either cap-dependent or cap-independent mechanisms. Among the proteins tested, HAV proteinase 3C suppressed viral IRES-dependent translation. Furthermore, 3C cleaved the polypyrimidine tract-binding protein (PTB) whose interaction with the HAV IRES had been demonstrated previously. The combined results suggest that 3C-mediated cleavage of PTB might be involved in down-regulation of viral translation to give way to subsequent viral genome replication. [source] Hepatitis A seroprevalence and demographics in Turkish children in AnkaraPEDIATRICS INTERNATIONAL, Issue 1 2009Rukiye U. Sac Abstract Background:, Hepatitis A virus (HAV) is the most common cause of hepatitis in childhood and an important public health problem. The objective of the present study was to determine the seroprevalence of hepatitis A and patient demographics in children between 1 and 15 years old who were admitted to a pediatric outpatient clinic in Ankara, Turkey. Methods:, Hepatitis IgM and G antibodies were determined in the sera of children who attended the outpatient clinic. Informed consent was obtained from all subjects or their parents. Results:, The mean age of the children (n = 335) was 7.9 ± 2.1 years; 47.5% of them were girls. The overall anti-HAV IgG prevalence in children aged 1,15 years was 47.2%. The positivity of hepatitis A IgM was highest in the 6,10 years age group (22.7%; P < 0.001). HAV IgG was highest in the 11,15 years age group (69.4%; P < 0.001). A total of 95.6% of the children had social insurance, 49.3% were living in poverty. The socioeconomic level of 82.4% of subjects was low. The history of hepatitis in their families was 6.9%. Conclusions:, Hepatitis A is intermediate endemic in Ankara and children must be vaccinated before school age, in addition to health education and improved sanitation. [source] Helicobacter pylori and Hepatitis a Virus Infection in School-Aged Children on Two Isolated Neighborhood Islands in TaiwanHELICOBACTER, Issue 3 2003Liang-Kung Chen ABSTRACT Background. The transmission routes of Helicobacter pylori and hepatitis A virus (HAV) infections have been extensively discussed in previous literature. However, whether H. pylori and HAV shared the same transmission pattern or not remains unclear. Lower socioeconomic status was recognized as a consistent risk factor to both infections. However, whether fecal-oral transmission was a risk factor to both infections is still under debate. Materials and Methods. In 1996, we conducted a cross-sectional study to evaluate the seroprevalence of antibody to H. pylori and HAV among the randomly selected school-aged children (age between 13 and 15) on Green Island (n = 91) and Lanyu Island (n = 138) (two isolated neighborhood islands near Taiwan Main Island). Results. The seroprevalence of H. pylori and HAV on the Green Island were 82.4% and 5.5%, respectively. The seroprevalence of H. pylori and HAV on Lanyu Island were 71.0% and 90.6%, respectively. H. pylori seroprevalence of all children and the subgroup of 13-year-olds was significantly lower on Lanyu Island than Green Island. However, it was not significantly different in subgroups of 14- and 15-year-olds. HAV seroprevalence was significantly higher on Lanyu Island than Green Island among all children and in each age subgroup. The correlation of H. pylori infection and HAV infection did not demonstrate significant linear correlation on both islands. Conclusions. In conclusion, H. pylori and HAV infections in school-aged children of 13,15 years of age on Green Island and Lanyu Island did not demonstrate significant correlation. The results of this study imply that H. pylori and HAV may share different transmission routes of infection. [source] Cocirculation of and coinfections with hepatitis A virus subgenotypes IIIA and IB in patients from Pune, western IndiaHEPATOLOGY RESEARCH, Issue 2 2007Shobha Chitambar Aim:, During the 1990s, a changing pattern of epidemiology of hepatitis A was reported in different populations of India. The present study was undertaken to investigate the molecular epidemiology of hepatitis A virus (HAV) strains over a period of 10 years. Methods:, Stool/serum samples were collected from hepatitis A patients clinically presenting acute viral hepatitis and hepatic encephalopathy. Reverse transcriptase polymerase chain reaction (RT-PCR) was performed to detect HAV-RNA. HAV genomes were examined by sequencing PCR products of VP1/2A junction (168 bp) and RNA polymerase (116 bp) regions. Results:, Subgenotype IIIA and IB were detected in 74.2% and 9.7% of specimens, respectively, while 16.1% of patients had mixed infections. Sewage samples also showed presence of both IIIA (9/10) and IB (1/10) subgenotypes. RNA polymerase region showed two clusters constituting 51.6% and 19.4% strains closer to Nor21 and HM175 strains, respectively, in clinical specimens. Three isolates appeared as discordant subgenotypes in VP1/2A and RNA polymerase regions. Conclusion:, The data revealed cocirculation of and coinfection with subgenotypes IIIA and IB, with predominance of IIIA and genetic heterogeneity of HAV strains in western India. [source] Experimental hepatitis A virus (HAV) infection in cynomolgus monkeys (Macaca fascicularis): evidence of active extrahepatic site of HAV replicationINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 1 2010Luciane A. Amado Summary This work studied the replication sites of hepatitis A virus (HAV) in cynomolgus monkeys (Macaca fascicularis) after intravenous inoculation. The cynomolgus monkeys were inoculated with the Brazilian hepatitis A virus strain (HAF-203). Monkeys were euthanized on days 15, 30, 45 and 60 postinoculation (pi). Liver samples, submandibular salivary gland, mesenteric lymph node and tonsils were removed for virological and pathological evaluation. Immunofluorescence analyses on liver and salivary gland sections using confocal laser scanning microscopy revealed the presence of HAV antigen (HAV Ag). The presence of HAV genome was monitored by real-time PCR. The HAV RNA was detected at 7 days postinoculation (dpi), concomitantly in serum, saliva and faeces. The highest HAV viral load was observed in faeces at 15 dpi (105 copies/ml), followed by serum viral load of 104 copies/ml at 20 dpi and saliva viral load of 103 copies/ml at 7 dpi. The animals showed first histological and biochemical signs of hepatitis at 15 dpi. The HAV antigen (Ag) was present from day 7 until day 60 pi in the liver and salivary glands. The HAV replicative intermediate was also detected in the liver (4.5 × 104 copies/mg), salivary glands (1.9 × 103 copies/mg), tonsils (4.2 × 101 copies/mg) and lymph nodes (3.4 × 101 copies/mg). Our data demonstrated that the salivary gland as an extrahepatic site of early HAV replication could create a potential risk of saliva transmitted infection. In addition, the cynomolgus monkey was confirmed as a suitable model to study the pathogenesis of HAV human infection. [source] A national study on the residential impact of biological aerosols from the land application of biosolidsJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2005J.P. Brooks Abstract Aims:, The purpose of this study was to evaluate the community risk of infection from bioaerosols to residents living near biosolids land application sites. Methods and Results:, Approximately 350 aerosol samples from 10 sites located throughout the USA were collected via the use of six SKC Biosamplers®. Downwind aerosol samples from biosolids loading, unloading, land application and background operations were collected from all sites. All samples were analysed for the presence of HPC bacteria, total coliform bacteria, Escherichia coli, Clostridium perfringens, coliphage, enteroviruses, hepatitis A virus and norovirus. Total coliforms, E. coli, C. perfringens and coliphage were not detected with great frequency from any sites, however, biosolids loading operations resulted in the largest concentrations of these aerosolized microbial indicators. Microbial risk analyses were conducted on loading and land application operations and their subsequent residential exposures determined. Conclusions:, The greatest annual risks of infection occurred during loading operations, and resulted in a 4 × 10,4 chance of infection from inhalation of coxsackievirus A21. Land application of biosolids resulted in risks that were <2 × 10,4 from inhalation of coxsackievirus A21. Overall bioaerosol exposure from biosolids operations poses little community risk based on this study. Significance and Impact of the Study:, This study evaluated the overall incidence of aerosolized micro-organisms from the land application of biosolids and subsequently determined that microbial risks of infection were low for residents close to biosolids application sites. [source] Molecular epidemiology of hepatitis A virus in Korea,JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 5 2001Kwan Soo Byun Abstract Background: The prevalence of antibodies for hepatitis A virus (anti-HAV) in adolescents and young adults has decreased remarkably following the economic growth in Korea. As a result, this age group has a high risk for HAV infection paradoxically, and over 1500 cases of clinically overt hepatitis A occurred in 1998. Human isolates of hepatitis A virus (HAV) are categorized within four genotypes (I, II, III, and VII). In some geographic regions, closely related isolates cluster, suggesting endemic spread of the virus, while in other regions multiple genotypes circulate. Virtually no data are available with regard to the genetic relatedness of Korean strains of HAV. Methods and Results: A 168 base pair segment encompassing the putative VP1/2A junction of the HAV genome was amplified by RT-PCR and sequenced in sera of 18 Korean patients with a sporadic form of acute hepatitis A. Pairwise comparisons of the nucleic acid and amino acid sequences of 18 Korean isolates with one another revealed that the Korean isolates showed > 94.6% and > 96.4% identity, respectively. All of the 18 Korean isolates clustered within genotype IA, irrespective of the geographic locations and the time that hepatitis occurred. Unique amino acid sequence changes that had never been reported in genotype IA were found in nine of the 18 isolates. These changes were Gln,Ser and Lys,Arg in 2A-19 and 2A-10 amino acid positions. Conclusion: The presence of single genotype and unique mutations may be related with the circulation of endemic HAV over a long period of time in Korea. [source] Molecular epidemiology of hepatitis A in St. Petersburg, Russia, 1997,2003JOURNAL OF MEDICAL VIROLOGY, Issue 6 2007Irja Davidkin Abstract The molecular epidemiology of hepatitis A virus (HAV) strains circulating in the St. Petersburg and Karelia regions was studied during 1997,2003. Hepatitis A virus RNA was isolated from both clinical samples (stools or sera) and environmental samples (sewage water). RT-PCR was carried out using different primer pairs from the VP1/2A and VP1 genomic regions, the variable parts of the HAV genome. PCR products were sequenced and 306 nucleotides from the VP1/2A and 332 nucleotides from the VP1 region were used for phylogenetic analysis. The results show that the IA subtype was the most common during the follow-up period: >90% of the isolated HAV strains belonged to that subtype. The HAV strains found in intravenous drug users belonged to subtypes IA and IIIA. Only one out of a total of 88 sequenced strains was of the IB subtype. The subtypes IB and IIIA were found only in 2001,2003, which suggests that new strains were introduced into the endemic situation. The results indicate the usefulness of molecular epidemiological methods in studying changes in the circulating HAV strains and in tracing transmission routes. J. Med. Virol. 79: 657,662, 2007. © 2007 Wiley-Liss, Inc. [source] Molecular epidemiology of hepatitis A virus in a group of Portuguese citizens living in Lisbon areaJOURNAL OF MEDICAL VIROLOGY, Issue 5 2007L. Rodrigues Abstract Hepatitis A virus (HAV) is the most important cause of acute infectious hepatitis worldwide. In Portugal, due to improvements in sanitation epidemic outbreaks of HAV infection have become less frequent. This report is the first, to our knowledge that characterized HAV in Portugal. For the detection and molecular characterization of HAV cases in a group of Portuguese individuals in the Lisbon area, 31 serum samples were tested: 8 from symptomatic children from an acute hepatitis A outbreak in a Roma (Gipsies) community (2004,2005), and 22 from patients with acute HAV from sporadic cases (2005,2006). A sample of CSF involved in a case of meningitis was also included. IgM anti-HAV detection and nested reverse transcription (RT-PCR), with primers located at the VP1-P2a region, was undertaken to detect HAV genome. In positive samples, molecular characterization was followed by phylogenetic analysis. All samples (n,=,31) were positive for IgM anti-HAV. HAV RNA was found in 96.7% of cases. All isolates were classified as genotype I: 22 belonged to sub-genotype IA (73.3%), and 8 to sub-genotype IB (26.7%). All strains obtained from an acute HAV outbreak had sub-genotype IA, in which seven isolates (87.5%) had identical sequences. In HAV sporadic cases sub-genotypes IA and IB were identified, and this may reflect the co-circulation of these two sub-genotypes in Portugal. Molecular epidemiology of HAV infection in this group of Portuguese appears to be similar to other European countries. HAV phylogenetic studies can provide important information for the design of appropriate public health measures. J. Med. Virol. 79:483,487, 2007. © 2007 Wiley-Liss, Inc. [source] Different transmission patterns of hepatitis A virus for two main risk groups as evidenced by molecular cluster analysis,JOURNAL OF MEDICAL VIROLOGY, Issue 5 2007Grace Tjon Abstract Men who have sex with men and traveling children are the most important risk groups for transmission of hepatitis A virus (HAV) in Amsterdam, The Netherlands. Between these two risk groups, different HAV genotypes are found. In this study the patterns of introduction and transmission of HAV were investigated in the two groups. HAV sequences from Amsterdam patients were divided according to risk: (I) travelers and their contacts, (II) homosexual men and their contacts. The sequences in each risk group were then grouped into clusters based on the genetic distances between the sequences. Among travelers many sporadic cases were found, the clusters were small, and introduced frequently into the population, mostly in the second half of each calendar year, indicating a seasonal pattern of introduction and transmission after the summer holidays. Among men who have sex with men the clusters were bigger and remained present for a longer time; sporadic cases were few, and introduction of new strains occurred only occasionally but throughout the year. Our findings indicate that new HAV strains are frequently imported into Amsterdam by travelers, but they are limited in the extent and season of their spread. In contrast, HAV is only occasionally imported into the male homosexual and bisexual population, but remains endemic and spreads to a large number of individuals without a seasonal pattern. J. Med. Virol. 79:488,494, 2007. © 2007 Wiley-Liss, Inc. [source] Molecular epidemiological studies show that hepatitis A virus is endemic among active homosexual men in EuropeJOURNAL OF MEDICAL VIROLOGY, Issue 4 2007Kathrine Stene-Johansen Abstract Large outbreaks of hepatitis A have occurred in Denmark, Germany, the Netherlands, Norway, Spain, Sweden, and the United Kingdom during the period 1997,2005 affecting homosexual men. A collaborative study was undertaken between these countries to determine if the strains involved in these hepatitis A outbreaks were related genetically. The N-terminal region of VP1 and the VP1/P2A region of the strains were sequenced and compared. The majority of the strains found among homosexual men from the different European countries formed a closely related cluster, named MSM1, belonging to genotype IA. Different HAV strains circulated among other risk groups in these countries during the same period, indicating that specific strains were circulating among homosexual men exclusively. Similar strains found among homosexual men from 1997 to 2005 indicate that these HAV strains have been circulating among homosexual men for a long time. The homosexual communities are probably too small within the individual countries to maintain HAV in their population over time, whereas the homosexual communities across Europe are probably sufficiently large to sustain continued circulation of homologous HAV strains for years resulting in an endemic situation among homosexual men. J. Med. Virol. 79:356,365, 2007. © 2007 Wiley-Liss, Inc. [source] Comparison of hepatitis A and E virus infections among healthy children in Mongolia: Evidence for infection with a subgenotype IA HAV in children,JOURNAL OF MEDICAL VIROLOGY, Issue 1 2007Bira Tsatsralt-Od Abstract To compare the epidemiologic profiles of hepatitis A virus (HAV) and hepatitis E virus (HEV) infections in children in Mongolia, the prevalence of HAV and HEV infections was investigated serologically and molecularly among 717 apparently healthy individuals of 0,20 years of age (mean,±,standard deviation, 8.6,±,4.9 years) using serum samples obtained between October 2005 and January 2006. Total antibody against HAV (anti-HAV [total]) was detected in 494 (68.9%) of the 717 subjects, while IgG antibody against HEV (anti-HEV IgG) was detected in only five subjects (0.7%) (P,<,0.0001). All five subjects who had anti-HEV IgG, were negative for anti-HEV IgM and HEV RNA. Anti-HAV was detectable in 24 (75.0%) of the 32 infants aged 7 days to 6 months, but not in any of the 8 infants aged 7 to <12 months. The prevalence of anti-HAV was 19.5% (17/87) in the age group of 1,3 years, and it increased to 50.0% (69/138) in the age group of 4,6 years, and further to 81.4% (105/129) in the age group of 7,9 years. Of note, 97.2% of the subjects in the age group of 16,20 years had anti-HAV. The presence of HAV RNA was tested in all 717 subjects, and three children of 1, 4, or 8 years of age were found to have detectable HAV RNA (subgenotype IA). No subject had a history of hepatitis or jaundice. In conclusion, HEV infection was uncommon, but HAV infection lacking overt clinical features was prevalent among children in Mongolia. J. Med. Virol. 79:18,25, 2007. © 2006 Wiley-Liss, Inc. [source] Co-circulation of genotype IA and new variant IB hepatitis A virus in outbreaks of acute hepatitis in Hungary,2003/2004JOURNAL OF MEDICAL VIROLOGY, Issue 11 2006Gábor Reuter Abstract Hepatitis A virus (HAV) is one of the most important causes of acute infectious hepatitis worldwide. In Hungary, the reported number of HAV infections has been decreasing in the last four decades, nevertheless, still, each year 500,800 new cases and multiple outbreaks occur, particularly in the northeast region of Hungary. In Hungary, serology is used routinely to establish the diagnosis of HAV infection without genetic analysis of HAV strains for molecular epidemiology. In this study, serum samples collected from symptomatic patients were tested by enzyme-immunoassay (anti-HAV-IgM ELISA) to establish the cause of three acute hepatitis A outbreaks (outbreak 1,from low prevalence region in Southwest Hungary in 2003 and outbreaks 2 and 3 from the endemic region in Northeast Hungary in 2004). Outbreak strains were characterized by reverse transcription-polymerase chain reaction (RT-PCR) amplification of a 360 bp viral VP1/2A region, amplicon sequencing and phylogenetic analysis. Four, seven, and three sera from outbreaks 1, 2, and 3, respectively, were investigated by RT-PCR for HAV genome and HAV RNA was detected in 4 (100%), 4 (57%), and 2 (67%) samples. All strains belonged to genotype I HAV. Outbreak 1 was caused by the new variant subtype IB and outbreaks 2 and 3 caused by genetically identical subtype IA strains. The Hungarian IA and IB hepatitis A viruses had the highest nucleotide identity, 98.4% and 99.0%, to IT-SCH-00 and IT-MAR-02 strains, respectively, detected in year 2000 and 2002 in Italy. Endemic subtype IA and probably imported new variant subtype IB HAV viruses was detected in outbreaks of hepatitis in Hungary that are closely related genetically to HAV strains in Italy. J. Med. Virol. 78:1392,1397, 2006. © 2006 Wiley-Liss, Inc. [source] Distinct changing profiles of hepatitis A and E virus infection among patients with acute hepatitis, patients on maintenance hemodialysis and healthy individuals in Japan,JOURNAL OF MEDICAL VIROLOGY, Issue 8 2006Takehiro Mitsui Abstract To compare the epidemiologic profiles of hepatitis A virus (HAV) and hepatitis E virus (HEV) infections in Japan, the prevalence of clinical or subclinical HAV and HEV infections was investigated serologically and molecularly among 128 consecutive patients (age, mean,±,standard deviation, 37.5,±,14.7 years) who contracted acute hepatitis between 1989 and 2005 in a city hospital, and among 416 hemodialysis patients (60.1,±,12.6 years) and 266 medical staff members (34.6,±,11.4 years) at the same hospital, using stored periodic serum samples collected since the start of hemodialysis or employment, respectively. Between 1989 and 1995, among 93 patients with acute hepatitis, 51 (54.8%) were diagnosed with hepatitis A and only one patient with hepatitis E. Between 1996 and 2005, however, among 35 patients, only 3 (8.6%) were diagnosed with hepatitis A and 2 (5.7%) with hepatitis E. Although subclinical HEV infection was recognized in four hemodialysis patients (one each in 1979, 1980, 1988, and 2003) and two medical staff members (1978 and 2003) in previous studies, none of the 191 hemodialysis patients who had been negative for anti-HAV at the start of hemodialysis contracted HAV infection during the observation period of 7.6,±,6.4 years. Only one (0.4%) of the 246 medical staff members who had been negative for anti-HAV at the start of employment acquired hepatitis A during the observation period of 7.9,±,8.0 years: none had subclinical HAV infection. Clinical or subclinical HEV infection has occurred rarely during the last three decades, while HAV infection has markedly decreased at least since 1996. J. Med. Virol. 78:1015,1024, 2006. © 2006 Wiley-Liss, Inc. [source] Infection with hepatitis A, B, C, and delta viruses among patients with acute hepatitis in Mongolia,JOURNAL OF MEDICAL VIROLOGY, Issue 5 2006Bira Tsatsralt-Od Abstract 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. J. Med. Virol. 78:542,550, 2006. © 2006 Wiley-Liss, Inc. [source] A novel CD4+ T-helper lymphocyte epitope in the VP3 protein of hepatitis A virusJOURNAL OF MEDICAL VIROLOGY, Issue 4 2004Glňria Sánchez Abstract Prediction analysis of TH -cell epitopes in the VP3 capsid protein of the hepatitis A virus (HAV) revealed the occurrence of a putative TH epitope in the 102,121 region complying with all the algorithms tested. To confirm these predictions, spleen T lymphocytes obtained from BALB/c mice previously immunised with HAV, were stimulated in vitro with different concentrations of synthetic peptides 102,121 and 110,121 of VP3. The ability of these peptides to stimulate CD4+ T-helper lymphocytes proliferation was evaluated by an immunological flow cytometry detection of bromodeoxyuridine incorporation. Using this method, it is concluded that the amino terminal part of the VP3 102,121 sequence contains a T cell epitope. J. Med. Virol. 72:525,532, 2004. © 2004 Wiley-Liss, Inc. [source] Hepatitis in Albanian children: Molecular analysis of hepatitis A virus isolatesJOURNAL OF MEDICAL VIROLOGY, Issue 4 2004Rosanna Gabrieli Abstract Hepatitis A is a common disease in developing countries and Albania has a high prevalence of this disease associated to young age. In spite of the occurrence of a unique serotype there are different genotypes classified from I to VII. Genotype characterisation of HAV isolates circulating in Albania has been undertaken, as well as the study of the occurrence of antigenic variants in the proteins VP3 and VP1. To evaluate the genetic variability of the Albanian hepatitis A virus (HAV) isolates, samples were collected from 12 different cities, and the VP1/2A junction amplified and sequenced. These sequences were aligned and a phylogenetic analysis performed. Additionally, the amino half sequence of the protein VP3 and the complete sequence of the VP1 was determined. Anti-HAV IgM were present in 66.2% of all the sera. Fifty HAV isolates were amplified and the analysis revealed that all the isolates were sub-genotype IA with only limited mutations. When the deduced amino acid sequences were obtained, the alignment showed only two amino acids substitutions at positions 22 and 34 of the 2A protein. A higher genomic stability of the VP1/2A region, in contrast with what occurs in other parts of the world could be observed, indicating high endemicity of HAV in Albania. In addition, two potential antigenic variants were detected. The first at position 46 of VP3 in seven isolates and the second at position 23 of VP1 in six isolates. J. Med. Virol. 72:533,537, 2004. © 2004 Wiley-Liss, Inc. [source] Hepatitis A vaccine: Indirect evidence of immune memory 12 years after the primary courseJOURNAL OF MEDICAL VIROLOGY, Issue 2 2004Koen Van Herck MD Abstract Vaccine-induced hepatitis A antibodies persist up to 10 years in adults, with mathematical models estimating further persistence up to 20,25 years. Thirty-one adults received booster inoculations 12 years after their initial vaccination (HavrixÔ 720 El.U at months 0, 1, 6). At the time of booster inoculation, all still had detectable antibodies. All but one subject met pre-defined criteria for anamnestic response 14 days after the booster, and all subjects did so after 30 days. The subjects' geometric mean titre (GMT) increased rapidly from 242 IU/L at baseline to 3,832 IU/L at day 14 and 5,282 IU/L at day 30. This study shows a substantial immune response to re-exposure to hepatitis A antigen after 12 years, which occurs rapidly to ensure protection within the average incubation period of hepatitis A virus. J. Med. Virol. 72:194,196, 2004. © 2004 Wiley-Liss, Inc. [source] Seroprevalence of hepatitis A virus antibodies in Turkish and Moroccan children in Rotterdam,JOURNAL OF MEDICAL VIROLOGY, Issue 2 2004J.H. Richardus Abstract Seasonal fluctuations in hepatitis A have been observed in the Netherlands related to Turkish and Moroccan children after visiting their home countries. This study determined the prevalence and associated factors of hepatitis A virus (HAV) antibodies in Turkish and Moroccan children in Rotterdam. A random sample was taken of children in Rotterdam, aged 5,16 years, of Turkish and Moroccan origin, together with a random sample of native Dutch children aged 5,7 and 14,16 years. Blood was collected by finger prick on filter paper. IgG and IgM anti-HAV was detected by an enzyme-linked immunoassay (EIA). The 319 Turkish, 329 Moroccan, and 248 native Dutch children participated in the study. In Turkish children, IgG anti-HAV increased from 2.2% to 22.2% over the age groups. In Moroccan children, IgG anti-HAV increased from 10.2% to 57.7%. In native Dutch children, 0.8% had IgG anti-HAV in the youngest and 3.1% in the oldest age group. The percentage IgG-positive also having IgM anti-HAV was 21% in Turkish, and 41% in Moroccan children. No IgG-positive native Dutch children had IgM anti-HAV. The prevalence of IgG anti-HAV was associated with increased age, being Moroccan, longer stay in the country of origin before migrating to the Netherlands, and known contact to HAV. The majority of Turkish and Moroccan children aged 4,16 years in Rotterdam are not protected against HAV, but do have a high risk of becoming infected while visiting their native country. Active vaccination against HAV of these children is indicated, with as primary aim their own protection. Prevention of HAV-transmission in the general community should be seen as a secondary benefit. In addition, possible Dutch contacts of nonvaccinated Turkish and Moroccan children, such as day care workers and teachers, should also be vaccinated against HAV. J. Med. Virol. 72:197,202, 2004. © 2004 Wiley-Liss, Inc. [source] Time course of hepatitis A viremia and viral load in the blood of human hepatitis A patientsJOURNAL OF MEDICAL VIROLOGY, Issue 1 2004Andrea Normann Abstract The hepatitis A virus (HAV) is the most common etiological cause of acute hepatitis infections in humans in industrialized countries. Investigations into the viral load during HAV viremia, however, are rare. Therefore, correlation studies between viral load, biochemical, and specific serological markers have been undertaken. The group of sera comprised a series of multiple consecutive blood samples drawn from 11 patients at different times after onset of the disease. During the period up to 70 days after the onset of icterus, the individual range was at 1×103 to 3×104 HAV genome equivalents/ml. From day 75 until 120 after onset of the disease, the levels traced were at 103. In one case, it was possible to trace 1.25×104 genome equivalents/ml up to 180 days after onset of icterus and in two cases even up to 408 and 490 days viral load levels of 5×103 and 4×104 were detected, respectively. The same sera were used to measure IgM class antibodies to hepatitis A virus and the total anti-HAV. The results demonstrate that a direct correlation to peak levels of viral load exists with peak serum transaminase levels, but neither with peak anti-HAV IgM levels nor with total anti-HAV. Decreasing amounts of anti-HAV IgM tend to occur with decreasing amounts of HAV genome equivalents; and, vice versa, increasing amounts of total anti-HAV are accompanied by decreasing amounts of HAV genome equivalents. The longest duration of viremia was found in patients infected with HAV genotype IA. J. Med. Virol. 72:10,16, 2004. © 2004 Wiley-Liss, Inc. [source] Perinatal and intrafamily transmission of hepatitis B virus in three generations of a low-prevalence populationJOURNAL OF MEDICAL VIROLOGY, Issue 2 2003Katalin Ördög Abstract Family members of 47 hepatitis B virus (HBV)-carrier pregnant women were tested for the presence of hepatitis B surface antigen (HBsAg), other markers of HBV infection, and hepatitis A virus (HAV) antibodies. Eleven members of six families were found to be HBV DNA positive. Five of the anti-HBe-positive persons were found to be HBV DNA carriers, too. The mean age of the HBV DNA carriers was found to be lower than that of Hbe carriers; therefore, it is suggested that seroconversion to HBe occurs before the resolution of HBV DNA carrier state. Superinfection with hepatitis A virus was not found to influence the elimination of HBV-carrier state, as there was no correlation found between the hepatitis A exposure and the hepatitis B virus markers in the families. The low HBV prevalence in the population (0.3%) was in contrast to the high prevalence of the families of the HBV-carrier mothers (27.1%) and family members with HBV markers (50.4%). Significant positive correlation was found in the proportion of HBV-positive children, and the HBV history of their parents. When fathers were shown to be seronegative, the probability of HBV transmission was reduced by a factor of 6 (12.5% instead of 75%) probably due to reduced viral load and possibly by other factors. Several results indicate, that the noncytocidal hepatitis B virus clearing mechanism suggested by Guidotti et al. [1996, 1999] was effective also in the HBV-carrier human population. J. Med. Virol. 70: 194,204, 2003. © 2003 Wiley-Liss, Inc. [source] Characterization of hepatitis A virus isolates from subgenotypes IA and IB in Rio de Janeiro, Brazil,JOURNAL OF MEDICAL VIROLOGY, Issue 1 2002Vanessa S. de Paula Abstract Hepatitis A virus (HAV) isolates from around the world have been classified into seven genotypes (I,VII). Most human strains belong to genotype I, which has been divided into two subgenotypes, A and B. South America has provided a small number of strains studied at the genome level. In the present study, IgM anti-HAV antibodies were detected in 116 out of 250 (46%) serum samples collected from consecutive patients with acute hepatitis referred to the Brazilian Reference Center for Viral Hepatitis, Rio de Janeiro. Viral RNA were extracted from all 250 samples and submitted to a reverse transcription-polymerase chain reaction (RT-PCR) assay designed to amplify a genome segment in the VP1/2A junction region. HAV RNA was detected in 54/116 (47%) and 17/134 (13%) IgM anti-HAV-positive and -negative sera, respectively. In addition, HAV RNA was detected in 17/35 (49%) IgM anti-HAV-positive sera that had been collected at a day care center where cases of acute hepatitis were being observed for 3 months. Nucleotide sequences (168 bp) of PCR products were determined for 30 HAV isolates. Phylogenetic analysis showed that 21 belonged to subgenotype IB, while 9 were of subgenotype IA. Interestingly, a concomitant circulation of isolates from subgenotypes IA and IB was observed in the day care center. J. Med. Virol. 66:22,27, 2002. © 2002 Wiley-Liss, Inc. [source] Experimental hepatitis A virus infection in guinea pigsJOURNAL OF MEDICAL VIROLOGY, Issue 4 2001Britt Hornei Abstract Although many of the properties of hepatitis A virus (HAV) are known, several aspects of HAV pathogenesis are still not understood, such as the mechanism underlying the hepatotropism or HAV replication in extrahepatic sites. Detailed studies of these aspects were hampered mostly by the lack of accessible animal models, since only nonhuman primates are susceptible to experimental infections. An alternative animal model would also be of interest to assess the primary replication site and for the evaluation of the safety and efficacy of vaccines. A study was undertaken to determine whether HAV can infect guinea pigs and whether they are useful as a model for studying aspects of HAV pathogenesis and for the evaluation of vaccines. HAV variants adapted to primate or guinea pig tissue culture were used to inoculate guinea pigs intraperitoneally and by the oral route. The animals were observed for clinical disease, shedding of HAV in stools, viremia, seroconversion, evidence for liver damage by biochemical liver function tests, virus presence in the liver, development of hepatic histopathological changes, and occurrence of HAV in extrahepatic organs. The animals developed an active, clinically inapparent infection with specific histopathological changes in the liver. Although virus replication occurred, as shown by RT-PCR and isolation of infectious virus from feces and serum, it seems unlikely that guinea pigs are suitable for studying the clinical features of hepatitis A, because the clinical and laboratory parameters remained normal. However, guinea pigs appear useful for studying some aspects of HAV pathogenesis and for testing the safety of vaccines. J. Med. Virol. 64:402,409, 2001. © 2001 Wiley-Liss, Inc. [source] Has the time come to control hepatitis A globally?JOURNAL OF VIRAL HEPATITIS, Issue 2008Matching prevention to the changing epidemiology Summary., For the first time a global meeting on hepatitis A virus (HAV) infection as vaccine preventable disease was organized at the end of 2007. More than 200 experts from 46 countries gathered to investigate the changing global HAV epidemiology reflecting the increasing numbers of persons at risk for severe clinical disease and mortality from HAV infection. The benefits of childhood and adult hepatitis A (HepA) vaccination strategies and the data needed by individual countries and international health organizations to assess current HepA prevention strategies were discussed. New approaches in preventing HAV infection including universal HepA vaccination were considered. This introductory paper summarizes the major findings of the meeting and describes the changing epidemiology of HAV infections and the impact of HepA vaccination strategies in various countries. Implementation of HepA vaccination strategies should take into account the level of endemicity, the level of the socio-economic development and sanitation, and the risk of outbreaks. A stepwise strategy for introduction of HepA universal immunisation of children was recommended. This strategy should be based on accurate surveillance of cases and qualitative documentation of outbreaks and their control, secure political support on the basis of high-quality results, and comprehensive cost-effectiveness studies. The recognition of the need for increased global attention towards HepA prevention is an important outcome of this meeting. [source] Hepatitis A seroprevalence and its relationship with environmental factors in children of different age groups in Kahramanmaras, Eastern Mediterranean region of TurkeyJOURNAL OF VIRAL HEPATITIS, Issue 12 2007D. Kaya Summary., Hepatitis A infections are influenced by environmental and socioeconomic factors. Epidemiologic studies regarding hepatitis A virus (HAV) infection in Turkey have not previously examined these factors. We investigated HAV seroprevalence and its association with sociodemographic factors among children of various ages in the Eastern Mediterranean region of Turkey. The study included 1142 children (603 male and 539 female) between ages of 6 months and 18 years. Seropositivity in the whole group was 57.2%. HAV prevalence rates according to age groups were as follows: 35.5% in 6,23 months group, 19.2% in 2,5 years group, 74.3% in 6,10 years group, 83.0% in 11,14 years group, 92.8% in 15,18 years group. Risk factors that influenced seropositivity were; dense population, over-crowded families, excessive number of siblings, low socioeconomic status and low education of the mother. As HAV seroprevalence in children older than 6 years of age is high, we recommend hepatitis A vaccination in this region after the first year of life. [source] | ||||||||||||||||