Molecular Epidemiology of Hepatitis A Virus in the South-East Area of Gyeonggi-do in Korea

PURPOSE: Hepatitis A virus (HAV) has been a leading cause of acute hepatitis in Korea. The reported genotypes of acute hepatitis A in Korea are the subgenotype IA and IB. The aim of the present study is to investigate HAV genotypes in the south-east area of Gyeonggi-do in Korea. MATERIALS AND METHODS: From June 2004 to June 2006, 46 acute hepatitis A patients were enrolled prospectively. All had sporadic acute hepatitis A patients. All suspected cases of acute hepatitis A were tested for IgM anti-HAV antibodies. We sequenced 168 bp of nucleotides of the putative VP1/P2A junction and determined the HAV genotype with reverse transcriptase polymerase chain reaction. The clinical and laboratory results of all patients were recorded. RESULTS: HAV-ribonucleic acid (RNA) was detected in 41 samples out of 46 samples. Among the 41 samples, 25 (60%) were shown to have subgenotype IIIA and the other 16 (40%) were subgenotype IA. Several amino acid substitutions were found. CONCLUSION: In these HAV sporadic cases, IIIA and IA were identified, and this may reflect co-circulation of various genotypes in Korea. This study provides valuable new data on the genetic distribution of HAV and important information to help design appropriate public health measures.

Hepatitis A virus subgenotypes dissemination during a community outbreak in a surrounding region of Rio de Janeiro

From December 1999 to December 2001, many cases of hepatitis A were notified in the county of Belford Roxo involving individuals aged 0 to 79 years. Serum samples were collected to evaluate the prevalence of anti-hepatitis A virus (HAV) antibodies, to detect HAV-RNA and to correlate with possible risk factors of HAV infection. Serum samples were screened by commercial IgM and total anti-HAV antibody ELISA and HAV-RNA was isolated and subsequently amplified by reverse transcription-polymerase chain reaction (RT-PCR) at VP1/2A region, sequenced and analyzed. Total anti-HAV prevalence was 87.9 percent (203/231) and IgM anti-HAV prevalence was 38.7 percent (89/231). Multivariate analysis showed that individuals under 20 years old are risks groups to acquire the infection suggesting that hygienic habits of young subjects are the principal factor of transmission and so they could be the target for vaccine programs. HAV-RNA was amplified from 29 (32.5 percent) IgM anti-HAV positive patients and 26 samples were sequenced and classified into subgenotypes IB (8 isolates) and IA (18 isolates). Isolates classified into subgenotype IB were identical representing one distinct strain. We could observe both subgenotypes circulating during the study which suggests different sources of infection. Prophylactic measures as vaccination strategies added to improvements in hygienic and sanitary conditions would be highly effective to reduction of infection.

Co-circulation of Two Genotypes of Hepatitis A Virus from Sporadic Cases in Northeastern Area of Seoul, Korea / 대한진단검사의학회지

BACKGROUND: In previous studies, most hepatitis A virus (HAV) isolates had been genotype IA in Korea. Recently, a small number of different genotypes were reported with an upsurge of acute hepatitis by HAV. We investigated the distribution of HAV genotypes. METHODS: RNA was extracted from anti-HAV IgM positive sera which were collected from March 2007 to February 2008 at a tertiary care hospital in Northeastern Seoul, Korea. Nested reverse transcription (RT)-PCR and direct sequencing for VP1/P2A region of the HAV were performed. RESULTS: A total of 699 cases with suspected acute hepatitis were tested for anti-HAV IgM, and positive results were obtained in 56 sera (8.0%), which were collected 2 to 15 days (median, 7 days)after the onset of symptoms. Of the 56 seropositive samples, 52 (92.9%) were positive for HAV RNA, among which 28 isolates (53.8%) belonged to genotype IA and the remaining 24 (46.2%) belonged to genotype IIIA. Both IA and IIIA genotypes were isolated from 6-7 neighboring administrative districts throughout the year without geographic or seasonal restrictions. CONCLUSIONS: Co-circulation of two distinct HAV genotypes (IA and IIIA) was observed from the northeastern Seoul for the year studied.