METHODS: Screening of genotypes was performed by enzyme immunoassay and/or polymerase chain reaction INVADER method in 222 patients with HBV. The full-length nucleotide sequences of unusual strains were compared to those in the database, followed by construction of a phylogenetic tree.
RESULTS: Unusual HBV strains were isolated from two patients: a 27-year-old Japanese bisexual man with acute hepatitis B with HIV co-infection and a 52-year-old Japanese man with chronic hepatitis B. The former strain was classified as genotype H, showing an overall identity of 99.8% to the Thailand strain (EU498228), while the nucleotide sequence of the latter strain showed similarity to the genotype B strains isolated in Malaysia (JQ027316) and Indonesia (JQ429079) between DR2 and DR1 in the X region, with identities of 96.9%. However, this strain was classified as genotype H by full-length sequence analysis, and the sequence between nt2023 and nt2262 showed no similarity to that in any previously reported strains.
CONCLUSION: HBV strains showing recombination between genotype B and H strains were found even in chronic hepatitis patients in Japan. Globalization may yield HBV strains of possible novel genotypes containing novel nucleotide sequences in the precore/core region.
METHODS: A multisite cross-sectional study was conducted in HIV-infected patients currently <25 years old receiving antiretroviral treatment (ART) who had HBV surface antigen (HBsAg), or HBV surface antibody (anti-HBs) or HBV core antibody (anti-HBc) tested during 2012-2013. HBV coinfection was defined as having either a positive HBsAg test or being anti-HBc positive and anti-HBs negative, reflective of past HBV infection. HBV seroprotection was defined as having a positive anti-HBs test.
RESULTS: A total of 3380 patients from 6 countries (Vietnam, Thailand, Cambodia, Malaysia, Indonesia and India) were included. The current median (interquartile range) age was 11.2 (7.8-15.1) years. Of the 2755 patients (81.5%) with HBsAg testing, 130 (4.7%) were positive. Of 1558 (46%) with anti-HBc testing, 77 (4.9%) were positive. Thirteen of 1037 patients with all 3 tests were anti-HBc positive and HBsAg and anti-HBs negative. One child was positive for anti-HBc and negative for anti-HBs but did not have HBsAg tested. The prevalence of HBV coinfection was 144/2759 (5.2%) (95% confidence interval: 4.4-6.1). Of 1093 patients (32%) with anti-HBs testing, 257 (23.5%; confidence interval: 21.0-26.0) had positive tests representing HBV seroprotection.
CONCLUSIONS: The estimated prevalence of HBV coinfection in this cohort of Asian HIV-infected children and adolescents on ART was 5.2%. The majority of children and adolescents tested in this cohort (76.5%) did not have protective HBV antibody. The finding supports HBV screening of HIV-infected children and adolescents to guide revaccination, the use of ART with anti-HBV activity and future monitoring.