Prevalence of hepatitis B virus infection among tuberculosis patients with or without HIV in Goiânia City, Brazil.

BACKGROUND: Hepatitis B virus (HBV) and tuberculosis (TB) represent major public health problems. There is currently little data on HBV infection among TB patients with and without human immunodeficiency virus (HIV). OBJECTIVES: To assess HBV prevalence among TB patients with and without HIV. STUDY DESIGN: From April 2008 to March 2010, a cross-sectional study was conduct among TB patients attended at a reference hospital in Goiânia City, Brazil. The participants were tested for serological markers of HBV infection and HIV antibodies. HBV DNA was detected in HBsAg-positive samples, and also in HBsAg-negative/anti-HBc-positive samples to look for HBV occult infection. RESULTS: Of 425 patients, 402 (94.6%) agreed to participate in the study. The overall prevalence of HBV (HBsAg and/or anti-HBc positive) and HIV infections were 25.6% (103/402) and 27.6% (111/402), respectively. A higher HBV infection rate was found among HIV-infected patients (36.9%; 41/111) compared to patients infected with TB only (20.0%; 57/285). A multivariate analysis of risk factors showed that age ≥ 50 years (p=0.03), non-injecting (p<0.01) and injecting (p<0.01) drugs use were associated with HBV infection. Among the HBsAg-positive samples (n=13), HBV DNA was detected in 10 (76.9%) samples. Of the 90 anti-HBc-positive samples, 13 were HBV DNA positive (with very low levels) resulting in an occult HBV infection rate of 14.4%. PCR-RFLP was successfully performed in 20 HBV DNA-positive samples: 15 were genotype A and 5 were genotype D. CONCLUSIONS: HBV infection was common, particularly among this with HIV infection.

Genetic characterization of a Juquitiba-like viral lineage in Oligoryzomys nigripes in Rio de Janeiro, Brazil.

Hantaviruses, family Bunyaviridae, are rodent-borne RNA viruses that have caused cases of hantavirus cardiopulmonary syndrome (HCPS) in various regions of the Americas. There are five hantaviral lineages associated with HCPS in Brazil: Juquitiba virus (JUQV), Araraquara virus (ARAV), Laguna Negra-like virus (LNV), Castelo dos Sonhos virus (CASV), and Anajatuba virus (ANAJV). Three additional hantaviruses have been described in rodents alone: Rio Mearim virus, Jaborá virus, and a hantavirus lineage related to Seoul virus. This study describes the genetic detection and characterization of a Juquitiba-like hantavirus in Oligoryzomys nigripes, or the black-footed pygmy rice rat, in the Serra dos Orgãos National Park, Rio de Janeiro State, where so far no cases of HCPS have been reported.

Molecular epidemiology of hepatitis B virus in an isolated Afro-Brazilian community.

This study was conducted in an Afro-Brazilian, slave-descendant community with high (42.4%) hepatitis B virus (HBV) prevalence. Twenty (8.4%) out of the 239 subjects under study were HBsAg-positive, and HBV-DNA was detected in 59 (25%) individuals. A high rate (18.3%) of occult infection was therefore observed that was associated to low HBV loads (mean, 1.8 x 10(4) copies/ml) and to a specific amino acid substitution (C100Y) in the small surface antigen. Genotyping of 50 isolates showed that 43 (86%) were of subgenotype A1, one (2%) from subgenotype A2, and five (10%) from subgenotype D. Mixed genotypes A1 and E were observed in one (2%) sample. The genetic distance (0.8 +/- 0.3%) among the HBV/A1 isolates from the community was smaller than the intragroup divergence among A1 isolates from Brazil as a whole, but it was similar to that found between A2 isolates from different countries, suggesting that HBV/A1 was introduced in the community through different sources. The substitution W501R (polymerase), previously reported only in Gambia, was observed in 46% of the HBV/A1 isolates. The precore/core promoter region of HBsAg-positive isolates showed several substitutions that could explain the anti-HBe phenotype found in 18 of 20 (90%) of the HBsAg-positive subjects.

High proportion of subgroup A' (genotype A) among Brazilian isolates of Hepatitis B virus.

Hepatitis B virus (HBV) genotype A has been divided recently into two subgroups, designated A-A' (genotype A excluding A') and A'. Isolates belonging to subgroup A' have been identified in Africa. A new genotyping method, based on PCR amplification of the pre-S/S genome region and subsequent restriction fragment length polymorphism (RFLP) analysis, was developed, that established a correlation between RFLP subtypes and subgroups within genotype A. To investigate the occurrence of subgroup A' in South America, 119 Brazilian HBV isolates were analyzed. Ninety-three (78%) of them belonged to genotype A, with three predominating RFLP subtypes: 44 (37%) isolates were classified as AI, 30 (25%) were AII, and 18 (15%) were AIII. Pre-S/S nucleotide sequences of 15 genotype A isolates were determined. Phylogenetic analysis performed with these 15 and an additional 41 sequences revealed that isolates AI and AII clustered in subgroup A', whereas isolates AIII were classified into subgroup A-A'. The correlation RFLP subtypes-subgroups was confirmed by the presence of amino acid residues specific for subgroup A' in the surface antigens and polymerase of isolates AI and AII. The high proportion (63%) of isolates from subgroup A' suggested an African origin for a large number of Brazilian HBVs.