RESUMO
Hepatitis E virus (HEV) infection is one of the enterically transmitted types of hepatitis. The present study was undertaken to estimate the occurrence of HEV infection in sporadic acute hepatitis in Thailand. Serum samples were obtained from 614 suspected acute hepatitis patients at two large hospitals in Bangkok during 2008, 2009, and 2011. Acute hepatitis E was identified by the presence of anti-HEV IgM (4.8%) using indirect ELISA kits and/or HEV RNA (4.5%) by a semi-nested reverse transcription-polymerase chain reaction assay. HEV IgM was the most common marker for detection (77%) at diagnosis, either by positive HEV IgM alone or together with HEV RNA, whereas HEV RNA alone was detected in 23% of patients. Overall, 4.2% of cases (26 out of 614) were acute HEV infection with the highest attack rate in the elderly age group. In addition, nucleotide sequence analysis of five HEV samples revealed 92.8-99.8% homology. All viruses were clustered into HEV genotype 3 and were similar genetically to swine HEV strains previously detected in the same area. Therefore, the occurrence of HEV infection with closely related to swine genotype 3 was approximately 4-5% of acute hepatitis cases in Thailand. Anti-HEV IgM was the most common marker at diagnosis.
Assuntos
Vírus da Hepatite E/isolamento & purificação , Hepatite/epidemiologia , Hepatite/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Análise por Conglomerados , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hepatite/diagnóstico , Anticorpos Anti-Hepatite/sangue , Humanos , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Prevalência , RNA Viral/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Tailândia/epidemiologia , Adulto JovemRESUMO
AIMS: To survey for hepatitis A virus (HAV) and hepatitis E virus (HEV) contamination in edible bivalve shellfish. METHODS AND RESULTS: A total of 213 shellfish (52 oysters, 69 cockles and 92 mussels) collected from a culture farm and two retailed markets were investigated for HAV and HEV contamination by reverse transcription-polymerase chain reaction (RT-PCR) assay using HA2-HA1 (capsid region) and HE366-HE363 (ORF2/3 overlapping region) primers, respectively. It was found that 3.8% of the shellfish and 2.9 and 6.5% of the cockle and mussel, respectively, showed positive for HAV detection. Nucleotide sequencing of all the 8 HAV-positive shellfish revealed 97-100% similarity to HAV subgenotype IA. Interestingly, viruses were found more frequently in the gills than in digestive tissue (4.5%vs 0.5%, P = 0.045). All the shellfish were negative for HEV. CONCLUSION: Significant contamination of HAV in edible bivalve shellfish was observed. Beside digestive tissue, gills are one of the important samples for viral genome detection. SIGNIFICANCE AND IMPACT OF THE STUDY: HAV-contaminated shellfish can play a role as reservoirs and/or vehicles in faecal-oral transmission in Thailand, and further monitoring of such a contamination is required.
