Drug-resistant and immune-escape hepatitis B virus mutants, occult hepatitis B infection and coinfections in public hospital patients from Argentina.

Argentina exhibits low serological prevalence for Hepatitis B virus (HBV); however, occult hepatitis B infection (OBI) has been reported in blood donors, Amerindians and individuals coinfected with hepatitis C virus (HCV), and/or human immunodeficiency virus (HIV). The aim of this study was to analyze the genetic diversity of HBV and to evaluate serological marker associations and coinfections with HCV and HIV in patients attending and treated in a public hospital in the province of Buenos Aires, Argentina. A total of 189 HBV reactive samples (HBsAg and/or anti-HBc) were analyzed for HBV DNA characterization.

First molecular epidemiological study of hepatitis B and D in individuals infected with human T-lymphotropic virus 1/2 from Argentina.

Human T-lymphotropic virus 1/2 (HTLV-1/2), hepatitis B virus (HBV), and hepatitis D virus (HDV) share transmission routes. Argentina shows low prevalence of HTLV-1/2, HBV, and HDV infections; however, this situation may vary according to the geographic region and group studied. The aim of this study was to estimate the prevalence of HBV and HDV infections and detect both viral genotypes in HTLV-1/2 individuals from Argentina.

Health care importance of Treponema pallidum, Chagas' disease and Human immunodeficiency virus 1 among Amerindians of Argentina: an observational study.

The objective of this study was to estimate the prevalence of Treponema pallidum, Trypanosoma cruzi and Human immunodeficiency virus 1 (HIV-1) in five Amerindian populations of Argentina. A retrospective study was conducted among 857 Amerindian populations (112 Kollas, 298 Mbyá-guaraníes, 79 Sagua Huarpes, 368 Wichis) from 2007 to 2010. Screening and confirmation of T.

Hepatitis B virus and hepatitis D virus in blood donors from Argentina: circulation of HBsAg and reverse transcriptase mutants.

In Argentina, current procedures to ensure the safety of the blood supply for transfusion include the serologic detection of specific blood-borne infections. The aim of this study was to evaluate the prevalence and the genetic diversity of hepatitis B virus (HBV) and hepatitis D virus (HDV) in blood donor populations from two distantly located Argentine regions. Data from 56,983 blood donations from the Favaloro Foundation, in the city of Buenos Aires (Central Region), and the Central Blood Bank of Misiones Province (Northeast Region) were analyzed.

HDAg-L variants in covert hepatitis D and HBV occult infection among Amerindians of Argentina: new insights.

Background: Guidelines suggest that all HBsAg-positive patients should be tested for anti-HDV IgG antibodies and to confirm active hepatitis D virus (HDV) infection by detection of HDV RNA by reverse transcriptase (RT) polymerase chain reaction (PCR).

Objectives: The aim of this study was to determine the serological prevalence and molecular features of HDV within an Amerindian community from Argentina exhibiting positivity for HBsAg and/or anti-HBc total Ig.

Study Design: Forty-six plasma samples were tested for the detection of total anti-HDV antibodies by ELISA.

New natural variants of hepatitis B virus among Amerindians from Argentina with mainly occult infections.

Background: Hepatitis B virus infection is frequent among Amerindians. In Argentina HBV genotypes A, B, C, D, E, F and H were described in different populations, while some cases of occult hepatitis B infection (OBI) were reported in human immunodeficiency virus (HIV) coinfected patients.

Objective: To determine the prevalence, genetic diversity of HBV and to analyze the deduced amino acid sequence of both S and viral polymerase (P) genes among Amerindians of Argentina.

Predominance of human lymphotropic T cell virus type 2 subtype B in urban populations of Argentina.

Human T-lymphotropic virus subtype b (HTLV-2b) infection has been described among aborigines from Northern Argentina, while HTLV-2a has been described in an injecting drug user (IDU) from a Central region, similar to the situation in Spain, the United States, and Brazil. In this study, 22 of the 26 strains analyzed from blood donors and HIV-1(+) individuals were HTLV-2b (84.6%) clustering with Amerindian references, while 4 HIV-1(+) (15.

[Seroprevalence of HTLV-1/2 in blood donors from Misiones Province].

Human T-cell Lymphotropic viruses type 1 (HTLV-1), the first human oncoretrovirus to be discovered, is the etiologic agent of Adult T-cell Leukemia (ATL) and HTLV-1 Associated Mielopathy or Tropical Spastic Paraparesis (HAM/TSP). It is endemic worldwide, including the North of Argentina where both associated diseases have also been detected. No etiologic role has been described for HTLV-2, although it has been associated with HAM/TSP-like neurologic syndromes.