Serum samples were non-randomly obtained from apparently healthy inhabitants of 5 villages in the Amazonas State, Brazil. Sera were tested by enzyme immunoassay for the presence of hepatitis B surface antigen (HBsAg) and, if this was found, for antibody to hepatitis delta virus (HDV). Of 574 people tested, 96 (16.7%) were reactive for HBsAg and 33 of these (34.4%) for anti-HDV. The results were analysed according to sex, age and history of jaundice and showed a high prevalence of hepatitis B virus (HBV) and HDV infections in these asymptomatic persons, mainly in young people. The rates of prevalence observed in Amazonas for both HBV and HDV are perhaps among the highest in the world, demonstrating that these viruses are endemic in this region of Brazil.

Twenty-two vertically human immunodeficiency virus type 1 (HIV-1

In the present study we investigated the presence of infections by vaccinia-like viruses in dairy cattle from 12 counties in the state of Rio de Janeiro in the last 9 years. Clinical specimens were collected from adult animals with vesicular/pustular lesions mainly in the udder and teats, and from calves with lesions around the nose and mouth. A plaque reduction neutralization test (PRNT) was applied to search for antibodies to Orthopoxvirus; the vesicular/pustular fluids and scabs were examined by PCR, electron microscopy (EM) and by inoculation in VERO cells for virus isolation. Antibodies to Orthopoxvirus were detected in most cases. The PCR test indicated a high nucleotide homology among the isolates and the vaccinia viruses (VACV) used as controls. By EM, typical orthopoxvirus particles were observed in some specimens. The agents isolated in tissue culture were confirmed as vaccinia-like viruses by EM and PCR. The HA gene of the vaccinia-like Cantagalo/IOC virus isolated in our laboratory was sequenced and compared with other vaccinia-like isolates, showing high homology with the original Cantagalo strain, both strains isolated in 1999 from dairy cattle. Antibodies to Orthopoxvirus were detected in one wild rodent (genus Akodon sp.) collected in the northwestern region of the state, indicating the circulation of poxvirus in this area. Nonetheless, PCR applied to tissue samples collected from the wild rodents were negative. Vesicular/pustular lesions in people in close contact with animals have been also recorded. Thus, the vaccinia-like virus infections in cattle and humans in the state seem to be an expanding condition, resulting in economic losses to dairy herds and leading to transient incapacitating human disease. Therefore, a possible immunization of the dairy cattle in the state should be carefully evaluated.

According to the World Health Organization, hepatitis B virus (HBV) carriers account for 5% of the world population. These potential infection transmitter individuals can evolve from the asymptomatic condition to a severe hepatic damage and even hepatocellular carcinoma. A similar HBV epidemiological distribution is observed for hepatitis D virus (HDV) that shares the obligatory association to HBV for its replication (Smedile et al. 1981). Frequently related to HBV chronic carriers and less frequently to the acute disease forms (Colombo et al. 1983, Rizzetto et al. 1983, HDV antigen was identified by immunohistochemical assays in liver cell nuclei of patients with chronic persistent or chronic active hepatitis, hepatitis B surface antigens (HBsAg-positive) (Rizzetto et al. 1977). In South America HDV infection was first observed in Venezuela as a severe and fulminant attack among Yucpa indians (Purcell & Gerin 1983) and in Colombia where 60% of the individuals studied were simultaneously HBV and HDV reactive (Ljunggren et al. 1984). In Brazil, the Amazon Region endemicity for both viruses is well known (Figueiredo Mendes et al. 1984, Fonseca et al. 1986, Simonetti et al. 1986 showing high prevalence pattern compared to the other parts of the world (Purcell & Gerin 1983, Nordenfelt et al. 1983, Fonseca et al. 1988). This region is also endemic for yellow fever and it is thought whether another human hepatitis viruses had been introduced in this area by human serum present in vaccines against yellow fever, since there are observations on the occurrence of icterus in England and in Brazil, following vaccination against yellow fever in the 1930s and 1940s decades (Findlay & Mac Callum 1937, 1938, Soper & Smith 1938, Fox et al. 1942 dengue virus antigen research in this study, once the same pathological liver findings are observed in yellow fever and haemorrhagic dengue, such as hepatomegaly, focal visceral haemorrhages, focal necrosis, sinusoidal acidophilic bodies, Kupffer cell hypertrophy and portal tract mononuclear cell infiltration.To observe the simultaneous HBV and HDV antigen frequency and to detect yellow fever and dengue viral antigens in histological sections we studied 79 hepatic samples by immunohistochemical assays. Hepatic viscerotomy samples belong to the Yellow Fever Collection (Department of Pathology, Instituto Oswaldo Cruz, Brazil) created in the 1930s decade from an agreement between Brazilian Government and the Rockefeller Foundation International Division to study yellow fever in Brazil. MATERIALS AND METHODSMaterial -Seventy-nine paraffin-embedded hepatic samples collected from 1934 to 1967 were analyzed. Sixtynine samples were from the Labrea Region, State of Amazonas and ten random samples were from other different localities in the same state. The cases were diagnosed at that time as viral hepatitis, yellow fever, focal necrosis or hepatic atrophy according to clinical aspects and histopathological findings.Methods -Four or five micra thick paraffin-embedded histological sections were ...

Twenty-one vertically HIV-1 infected children were assessed for drug resistance genotyping. Eighteen children presented at least one mutation conferring resistance to the nucleoside reverse transcriptase inhibitors, and seven children presented resistance to the non-nucleoside inhibitors. Among them, two children in whom the therapy had been discontinued two to three years before testing presented K101E, K103N, and G190A mutations conferring resistance to all the non-nucleoside drugs available for treatment. Protease gene mutations conferring resistance to at least two to up to twelve drugs were reported in 12 children. Studies in HIV-infected children have a particular meaning, and with antiretroviral therapy becoming more widely available, surveillance of viral resistance regional levels is relevant for treatment guidelines, supporting the rational use of antiretroviral drugs by treatment programs. Additional larger studies are still required to give more information on HIV-1 drug resistance in pediatric patients.

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Human T lymphotropic virus type I (HTLV-I) is a retrovirus and the transmission occurs from mother to child, by sexual contact or by blood transfusion. This study was performed to evaluate the prevalence ratio of HTLV infection in a group of 389 pregnant women attending at Fernandes Figueira Institute, Fiocruz, in Rio de Janeiro, Brazil. The specimens were screened for HTLV antibodies by ELISA and reactive samples were submitted to a Western Blot (WB) for confirmation. Detection of HTLV-I provirus in DNA from peripheral blood mononuclear cells (PBMC) and breast milk mononuclear cells (BMMC) from the seropositive women, was performed by PCR using primers for LTR, tax, pol regions. Of the 389 pregnant women tested, four (1%) were HTLV-I seropositive and three were indeterminate in the WB. PCR was done in three of the seropositive cases and HTLV-I provirus was detected in PBMC and BMMC from two of them. Three blood samples (0.8%) that presented WB indeterminate patterns, were negative by PCR. Our data indicate that the frequency of HTLV-I infection among pregnant women is relatively high in Rio de Janeiro and that preventive measures against the vertical transmission of the virus must be adopted in Brazil.

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