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Presents a study that determined the risk behaviors and viral subtypes of HIV-1 found in 134 heterosexual HIV-seroprevalent maternity patients in Buenos Aires, Argentina. Materials and methods; Results and discussion.

Currently, data on HIV-1 circulating strains among men who have sex with men (MSM) in Argentina is scarce. In South America, the distribution and the prevalence of BF recombinants are dissimilar and exhibit an underappreciated heterogeneity of recombinant structures. Here, we studied for the first time the genetic diversity of HIV-1 BF recombinants and their evolution over time through in-depth phylogenetic analysis and multiple recombination detection methods involving 337 HIV-1 nucleotide sequences (25 near full-length (NFL) and 312 partial pol gene) obtained from Argentinean MSM. The recombination profiles were studied using multiple in silico tools to characterize the genetic mosaicism, and phylogenetic approaches to infer their relationships. The evolutionary history of BF recombinants and subtype B sequences was reconstructed by a Bayesian coalescent-based method. By phylogenetic inference, 81/312 pol sequences clustered within BF clade. Of them, 46 sequences showed a genetic mosaic with CRF12_BF-like patterns, including plausible second-generation recombinants. Other CRFs_BF like (CRF17, 28, 29, 39, 42, 44, 47) and probable URFs_BF were less frequently found. Phylogenetic and recombination analyses on NFL sequences allowed a meticulous definition of new BF mosaics of genomic patterns. The Bayesian analyses pointed out quite consistent onset dates for the CRFs_BF clade based on B and F gene datasets (~1986 and ~1991 respectively). These results indicate that the CRFs_BF variants have been circulating among Argentinean MSM for about 30 years. This study reveals, through growing evidence showing the importance of MSM in the dynamics of the HIV-1 epidemic in Argentina, the coexistence of CRF12_BF-like and high diversity of strains exhibiting several BF mosaic patterns, including non-reported URFs that may reflect active clusters as potential intervention targets to hinder HIV-1 transmission. [ABSTRACT FROM AUTHOR]

Introduction: The objective of this study was to explore the acceptability of rapid HIV self-testing (RHST) among men who have sex with men (MSM). Methods: During 2006–2009, a sample of 500 MSM was recruited through Respondent Driven Sampling for an HIV prevalence/incidence study. Attitude toward RHST was explored among HIV negative MSM. Data were weighted prior to analyses. Results: Participants reported they were likely to buy RHST (74%), test themselves more frequently than they currently do (77%), and that the procedure would simplify testing (70%). Furthermore, 71% reported they would probably use it alone, 66% would use it with a steady partner, and 56% with a friend/partner. While a majority acknowledged that RHST use would deprive them of receiving counseling (61%), 74% declared they would go for help if they tested positive; 57% would use an RHST in order to avoid condoms. Probability of use surpassed 70% among gay and non-gay identified MSM as well as those with and without a previous HIV test. Those likely to buy RHST were older (p = 0.025) and more likely to identify as gay (p = 0.036). A total of 17% said they would think about killing themselves and 9% would attempt suicide if they tested positive. These MSM were more likely to be younger (p<0.001), with lower mood level (p<0.001) and greater feelings of loneliness (p = 0.026). Conclusions: The high acceptability of RHST found among MSM should encourage the authorities to consider the possibility of offering it for self-testing, as it can improve early diagnosis and prevention of future transmissions. However, further research is needed to understand how to best disseminate RHST among MSM who wish to use it and to offer support and linkage to care for those who test HIV-positive. [ABSTRACT FROM AUTHOR]

Background: In Trinidad and the wider Caribbean, subtype B Human Immunodeficiency Virus-type 1 (HIV-1B) overwhelmingly accounts for HIV infection among heterosexuals; this contrasts with the association of HIV-1B with homosexual transmission and injecting drug use globally. The HIV envelope contains genetic determinants of cell tropism and evasion from immune attack. In this study we investigate the genetic properties of the env V1-C4 of HIV-1B soon after transmission to Trinidadian heterosexuals. This will reveal distinctive genetic features of the strains that cause the HIV-1B epidemic in Trinidad and generate insights to better understand their properties. Methodology/Principal Findings: Quasispecies sampling was performed on the env V1-C4 of HIV-1B strains soon after transmission to heterosexual Trinidadians in a cohort of seroconverters. Phylogenetic relationships were determined for these quasispecies and the length and number of asparagine (N) linked glycosylation sites (NLGS) in their variable loops compared to that for HIV-1B globally. Signature amino acids within the constant domains of the env V1-C4 were identified for heterosexually transmitted HIV-1B from Trinidad relative to HIV-1B globally. HIV-1B obtained from Trinidadian heterosexuals soon after seroconversion had significantly longer V2 loops with one more glycosylation site, shorter V3 loops and no significant difference in V1 or V4 when compared to HIV-1B obtained soon after seroconversion from infected individuals in the rest of the world. HIV-1B soon after seroconversion and during chronic infection of Trinidadians was not significantly different, suggesting that distinctly long V2 loops are characteristic of HIV-1B in Trinidad. A threonine deletion at position 319 (T319-) along with the substitutions R315K and S440R were found to be distinctly associated with HIV-1B from Trinidad compared to HIV-1B globally. Conclusions: This finding of distinctive genetic features that are characteristic of HIV-1B strains from Trinidad is consistent with the Trinidad epidemic being established by a founder strain or closely related founder strains of HIV-1B. [ABSTRACT FROM AUTHOR]

Objective To study socio-demographics, sexual practices, drug use behaviors, and prevalences of HIV, syphilis, hepatitis B and C, HTLV-1 and HTLV-2 in immigrant (foreigner) and non-immigrant (local/native) female sex workers (FSW). Design This was a cross-sectional study in immigrant and non-immigrant FSW living in Buenos Aires, Argentina. Participants were interviewed using a standardized questionnaire. Results A total of 625 FSW were enrolled, of whom 169 (27%) were immigrant FSW from Paraguay, the Dominican Republic, Brazil, Peru, and Uruguay. The prevalence of syphilis and hepatitis C was significantly higher among Argentinean FSW than among immigrant FSW. However, hepatitis B prevalence was higher among immigrant FSW. Adjusted risk factor analysis comparing immigrant FSW with Argentinean FSW indicated that marital status (single), occupation (none), fee per sex act (≤US$7), workplace (bar and cabaret), and anal sex with clients were significantly associated with immigrant FSW status. Conclusions Effective HIV/STI prevention and medical care programs need to be tailored to the specific needs of both FSW groups in Argentina. [ABSTRACT FROM AUTHOR]

The article estimates the prevalence of HIV and sexually transmitted infections among men who have sex with men (MSM) in Buenos Aires, Argentina. MSMs were tested for HIV, hepatitis B, hepatitis C (HCV), human T-cell lymphotropic viruses and Treponema pallidum infection. The study shows that the use of illegal drugs, blood transfusion history, and multiple sexual partners are associated with HCV.

Presents a study on the prevalence and risk factors for HIV transmission among female commercial sex workers in South America. Details on the dynamic nature of HIV epidemic; Analysis of the genetic variability among HIV-1 strains; Association between HIV seropositivity and condom use.

The article focuses on the study that determines the erythrocyte-associated p24 antigen in HIV-infected patients with undetectable plasma viral load for more than one year. HIV-1 linked to erythrocytes was detected through reverse transcriptase-polymerase chain reaction techniques in patients. The observation is useful to know if the virus keeps on replicating at the moment of deciding whether to interrupt or diminish treatment.