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.
Adolescent ; Adult ; Amino Acid Sequence ; Child ; Female ; Genotype ; Hepatitis A/*virology ; Hepatitis A Virus, Human/classification/*genetics/isolation & purification ; Humans ; Immunoglobulin M/blood ; Korea ; Male ; Middle Aged ; Molecular Sequence Data ; Phylogeny ; RNA, Viral/analysis ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA ; Viral Structural Proteins/genetics ; Young Adult