Co-circulation of genotypes IA and IB of hepatitis A virus in Northeast Brazil

Abstract

The Northeast region is the location of most cases of acute hepatitis A virus (HAV) in Brazil. In the present study, the genotypes of HAV strains from Pernambuco State, one of most populous states in the Northeast region, were characterized. Blood samples positive for anti-HAV IgM from 145 individuals (mean age = 29.1 years), collected during 2002 and 2003, were submitted to nested RT-PCR for amplification of the 5'non-translated region (5'NTR) and VP1/2A regions of the HAV genome. The VP1/2A and 5'NTR regions were amplified in 39 and 21% of the samples, respectively. Nucleotide sequencing was carried out in 46% of VP1/2A and in 53% of 5'NTR isolates. The identity in nucleotide sequence of the VP1/2A region ranged from 93.6 to 100.0%. Phylogenetic analysis of the VP1/2A sequences showed that 65% belong to sub-genotype IA and 35% to sub-genotype IB. Co-circulation of both sub-genotypes was observed in the two years studied. Distinct clusters of highly related sequences were observed in both sub-genotypes, suggesting endemic circulation of HAV strains in this area. In the 5'NTR isolates, 92.7-99.2% identity was observed and two isolates presented one deletion at position 413. Phylogenetic analysis showed that genotype IA strains cluster in the tree in the same way as genotype IB strains, but one IIIA isolate from Spain clusters with genotype IB strains. These results do not allow us to state that 5'NTR could be used to genotype HAV sequences. This is the first report of co-circulation of sub-genotypes IA and IB in this region, providing additional information about the molecular epidemiology of HAV strains in Brazil.

Molecular characterization of hepatitis A virus isolated from acute infections in Turkey

“…Genotype I is the most common genotype, and sub-genotype IA is more frequently detected than sub-genotype IB (15). Co-circulation of genotypes and sub-genotypes is also possible as IA and IB (16 In outbreaks, isolates are mainly the isolates of outbreak origin, because of the low accumulation of genetic changes in HAV RNA (3). In the present study, some isolates showed 100% sequence similarity, indicating that they originated from the same source.…”

Evidence of Hepatitis A Virus Person-to-Person Transmission in Household Outbreaks

“…Phylogenetic analysis of HAV isolates obtained from household outbreaks revealed a co-circulation of the subgenotypes IA and IB. Several studies have reported the co-circulation of subgenotypes IA and IB in Brazil [11], [12], [29]. In 10 families, it was possible to sequence HAV RNA from the index cases and their household contacts.…”

Full-Length Genomic Sequence of Subgenotype IIIA Hepatitis A Virus Isolate in Republic of Korea

“…Subgenotypes IA and IB are most often reported in Brazil, France, China, and Japan [12–14]. Subgenotype IA is the most common type worldwide, whereas subgenotype IB has been prevalent in the regions of Europe, Australia, and Mediterranean [15–18].…”