RESUMO
BACKGROUND: There are few surveillance studies analyzing genotypes or primary (transmitted) drug resistance in HIV-infected blood donors in Brazil. The aim of this study was to characterize patterns of HIV genotypes and primary resistance among HIV-seropositive donors identified at 4 geographically dispersed blood centers in Brazil. METHODS: All HIV-infected donors who returned for counseling at the 4 REDS-II Hemocenters in Brazil from January 2007 to March 2011 were invited to participate in a case-control study involving a questionnaire on risk factors. Viral sequencing was also offered to positive cases to assign genotypes and to detect and characterize primary resistance to reverse transcriptase and protease inhibitors according to World Health Organization guidelines. RESULTS: Of the 341 HIV-seropositive donors who consented to participate in the risk factor and genetics study, pol sequences were obtained for 331 (97%). Clade B was predominant (76%) followed by F (15%) and C (5%). Primary resistance was present in 36 [12.2%, 95% confidence interval (CI) 8.2 to 15.5] of the 303 individuals not exposed to antiretroviral therapy, varying from 8.2% (95% CI: 2.7 to 13.6) in Recife to 19.4% in São Paulo (95% CI: 9.5 to 29.2); there were no significant correlations with other demographics or risk factors. CONCLUSIONS: Although subtype B remains the most prevalent genotype in all 4 areas, increasing rates of subtype C in Sao Paulo and F in Recife were documented relative to earlier reports. Transmitted drug resistance was relatively frequent, particularly in the city of Sao Paulo which showed an increase compared with previous HIV-seropositive donor data from 10 years ago.
Assuntos
Doadores de Sangue , Farmacorresistência Viral/genética , Infecções por HIV/virologia , Soropositividade para HIV/sangue , HIV-1/genética , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética , Fármacos Anti-HIV/uso terapêutico , Sequência de Bases , Brasil , Estudos de Casos e Controles , Variação Genética , Genótipo , HIV-1/fisiologia , Humanos , Dados de Sequência Molecular , Vigilância de Evento Sentinela , Análise de Sequência de RNA , Inquéritos e Questionários , Carga ViralRESUMO
A prototype assay was used to genotype integrase (IN) from 120 HIV-1- infected IN inhibitor-naive adults from Argentina, Brazil, Cameroon, South Africa, Thailand, and Uganda. Subtype designations based on analysis of pol IN sequences were A (14), B (15), C (12), D (11), F (12), G (7), H (1), CRF01_AE (9), CRF02_AG (34), CRF22_01A1 (4), and CRF37_cpx (1). Ten (8.3%) of 120 samples had mutations associated with reduced susceptibility to the IN inhibitors, raltegravir and elvitegravir. Two samples had E92Q (both subtype B) and eight had E157Q (2A, 1C, 1D, 1F, 3 CRF02_AG). Some samples had other mutations selected by these drugs including T97A, and some had amino acid polymorphisms at positions associated with raltegravir and elvitegravir resistance. Mutations associated with other investigational HIV IN inhibitors were also identified. This suggests that HIV strains may vary in their natural susceptibility to HIV IN inhibitors.
Assuntos
Infecções por HIV/virologia , Integrase de HIV/genética , HIV-1/classificação , HIV-1/genética , Argentina , Brasil , Camarões , Análise por Conglomerados , Farmacorresistência Viral , Genótipo , Inibidores de Integrase de HIV/farmacologia , Humanos , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Filogenia , Análise de Sequência de DNA , Homologia de Sequência , África do Sul , Tailândia , UgandaRESUMO
In the Brazilian HIV-1 epidemic subtypes B, C, and F1 are cocirculating in the high risk population groups, and there is a high prevalence of intersubtype recombinant forms. The dynamic nature of the HIV epidemic in Brazil led us to study HIV-1 subtypes present in HIV-infected blood donations collected from 2001 to 2003. Donations from 91 seropositive donors were evaluated. Genetic subtype was obtained for 88 specimens based on sequence analysis of gag p24, pol IN, and env gp41 IDR. HIV-1 subtype B was the predominant strain present in the donor population (73.9%). A significant prevalence of intersubtype recombinants of subtypes B and F1 was found (22.7%). Subtype C (1.1%) and F1 (2.3%) were rare. None of the B/F1 recombinants is CRF28_BF or CRF29_BF. The high level of unique B/F1 recombinant strains in this population demonstrates the dynamic and complex nature of the HIV epidemic in Brazil.
Assuntos
Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , Doadores de Sangue , Brasil/epidemiologia , Genótipo , Proteína do Núcleo p24 do HIV/genética , Proteína gp41 do Envelope de HIV/genética , HIV-1/isolamento & purificação , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Recombinação Genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genéticaRESUMO
The high level of HIV genetic diversity has important implications for screening, diagnostic testing and patient monitoring. Continued diversification and global redistribution of HIV groups, subtypes and recombinants make it imperative that serological and molecular assays be designed and evaluated to ensure reliable performance on all HIV infections. Recognizing the importance of this issue, we initiated a comprehensive program to monitor global diversification of HIV, search for newly emerging variants, assemble large-volume panels of genetically and geographically diverse strains, and develop strategies to determine the impact of HIV diversity on assays used for detecting and monitoring HIV infection. Efforts to identify and characterize rare and emerging HIV strains have lead to the identification of HIV-1 group O, group N, and dual infections of groups M and O. A panel of plasma specimens was established that includes specimens collected from 12 countries in Africa, Asia, Europe, and South America; the panel comprises infections due to HIV-1 group M subtypes A, B, C, D, F, and G, as well as CRF01, CRF02, and unique recombinant forms, group N, and group O. Serological and molecular characterization of this unique panel has provided vital sequence data to support assay development and an invaluable source of well-defined specimens to evaluate and compare assay performance. The ability to address the challenge posed by ongoing evolution of HIV and the emergence of new variants requires continued surveillance of global HIV strain diversity, a sound scientific foundation for assay development, and suitable panels to evaluate and validate assay performance.
Assuntos
Variação Genética , Infecções por HIV/virologia , HIV-1/genética , HIV-2/genética , África , Ásia , Bioensaio , Europa (Continente) , Evolução Molecular , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , HIV-1/classificação , HIV-1/imunologia , HIV-1/isolamento & purificação , HIV-2/classificação , Humanos , Epidemiologia Molecular , Kit de Reagentes para Diagnóstico/virologia , Sensibilidade e Especificidade , América do SulRESUMO
The combination of automated sample preparation and real-time RT-PCR for measurement of HIV-1 viral load has the potential to significantly enhance throughput, reduce operator-associated error, and increase assay sensitivity and dynamic range. In this study, RNA was extracted from the plasma of 91 HIV-1 seropositive Brazilian blood donors using the Abbott m2000sp automated sample preparation system. Viral loads measured using the RealTime HIV-1 (RealTime HIV-1) assay and the Abbott m2000rt instrument were compared to values obtained in the LCx HIV RNA quantitative assay. Subtype was determined for 89 of 91 specimens by sequence/phylogenetic analysis of three genomic regions: gag p24, pol integrase, and env gp41. The panel included 69 subtype B, 1 C, 2 F, and 17 recombinant strains. Eighty-seven specimens were quantified by both assays. Two specimens were quantified only in RealTime HIV-1. Two additional specimens below the detection limit of both assays were also negative on PCR amplification. Viral load results were highly correlated, and good agreement was observed between assays with 90% of values within 0.5 log(10)copies/ml. The RealTime HIV-1 assay and m2000 system offer the advantages of automation while providing reliable quantification of diverse HIV strains.