Fig 1.
Identification of occult HBV infection among HIV treatment naïve patients.
HBsAg negative/ HIV positive individuals were screened for the presence of HBV DNA to identify occult HBV infection. The HBsAg negative group was stratified into anti-HBc positive and anti-HBc negative groups.
Table 1.
Baseline clinical and demographic characteristics.
Fig 2.
Comparative analysis of the clinical characteristics associated with chronic versus occult HBV infection in HIV-positive patients.
(A) CD4 T-cell count, (B) ALT, and (C) HBV DNA titres are represented as box and whisker plots for both infection groups. The box represents the 25% to 75% inter-quartile (IQR) range, with a line at the median value, while the whiskers represent the lowest and the highest values. The CD4 status, ALT, and AST levels were significantly elevated among the chronic compared to the occult patients.
Fig 3.
Phylogenetic analysis of occult and chronic HBV strains circulating among HIV-infected individuals in eastern India.
The phylogenetic relatedness was analyzed by means of Bayesian Markovchain Monte Carlo (MCMC) approach using a chain length of 50,000,000 and sampling in every 5000th generation and was based on the small surface (S) gene (nt 155–835 from EcoRI site). The occult HBV isolates (represented in red and labelled with O-) and the chronic HBV isolates (represented in green and labelled with C-) were analyzed with respect to GenBank reference sequences (represented in black) which are designated by their respective accession numbers along with their HBV genotypes/subgenotypes and country of origin. Posterior probabilities ≥0.9 are shown. HBV/D was the predominant genotype both among chronic (68.1%) and occult (82.4%) subjects, with HBV subgenotype D1 being widespread in OBI (64.7%) and D2 in chronic infection (42%).
Fig 4.
Relatedness of 5 occult HBV strains based on complete genome analysis.
The phylogenetic analysis was performed by Bayesian inference using a chain length of 50,000,000 and sampling in every 5000th generation. The occult HBV strains (represented by in red and also by O-) were compared to complete genome reference sequences from GenBank. Posterior probabilities ≥0.9 are shown.
Fig 5.
Signature pattern analysis of HBV surface gene between chronic and occult HBV/D1 strains found in HIV-positive individuals.
The complete HBV small surface ORF was compared between chronic HBV/D1 (n = 8) and occult HBV/D1 strains (n = 11). The major substitution to be detected was at the codon 129 where a Glutamine to Arginine substitution took place. Occult HBV sequences are labelled as O-, whereas the chronic HBV sequences are labelled as C-. The analysis was performed with a threshold value of 0.9.
Fig 6.
Intrapatient quasispecies diversity of the small surface ORF from chronic and occult HBV/D strains.
Scatter Plots were generated for (A) genetic divergence (%), (B) Shannon entropy, and (C) dN-dS for both groups. 8 chronic and 11 occult HBV/D subjects were included with 10 clones from each individual was sequenced to evaluate quasispecies diversity. Each ■ and ● represents the mean of individual patient values for the occult HBV and chronic HBV groups, respectively, whereas the horizontal bars represent the overall median values for each group.
Table 2.
Mutational analysis of the HBV polymerase and surface ORFs for the occult HBV subjects.