RESUMO
BACKGROUND: Variants in HIV-coreceptor C-C chemokine receptor type 5 (CCR5) and Human leukocyte antigen (HLA) genes are the most important host genetic factors associated with HIV infection and disease progression. Our aim was to analyze the association of these genetic factors in the presence of clinical symptoms during Primary HIV Infection (PHI) and disease progression within the first year. METHODS: Seventy subjects diagnosed during PHI were studied (55 symptomatic and 15 asymptomatic). Viral load (VL) and CD4 T-cell count were evaluated. HIV progression was defined by presence of B or C events and/or CD4 T-cell counts <350 cell/mm3. CCR5 haplotypes were characterized by polymerase chain reaction and SDM-PCR-RFLP. HLA-I characterization was performed by Sequencing. RESULTS: Symptoms during PHI were significantly associated with lower frequency of CCR5-CF1 (1.8% vs. 26.7%, p = 0.006). Rapid progression was significantly associated with higher frequency of CCR5-CF2 (16.7% vs. 0%, p = 0.024) and HLA-A*11 (16.7% vs. 1.2%, p = 0.003) and lower frequency of HLA-C*3 (2.8% vs. 17.5%, p = 0.035). Higher baseline VL was significantly associated with presence of HLA-A*11, HLA-A*24, and absence of HLA-A*31 and HLA-B*57. Higher 6-month VL was significantly associated with presence of CCR5-HHE, HLA-A*24, HLA-B*53, and absence of HLA-A*31 and CCR5-CF1. Lower baseline CD4 T-cell count was significantly associated with presence of HLA-A*24/*33, HLA-B*53, CCR5-CF2 and absence of HLA-A*01/*23 and CCR5-HHA. Lower 6-month CD4 T-cell count was associated with presence of HLA-A*24 and HLA-B*53, and absence of HLA-A*01 and HLA-B*07/*39. Moreover, lower 12-month CD4 T-cell count was significantly associated with presence of HLA-A*33, HLA-B*14, HLA-C*08, CCR5-CF2, and absence of HLA-B*07 and HLA-C*07. CONCLUSION: Several host factors were significantly associated with disease progression in PHI subjects. Most results agree with previous studies performed in other groups. However, some genetic factor associations are being described for the first time, highlighting the importance of genetic studies at a local level.
Assuntos
Soropositividade para HIV/genética , Antígenos HLA/genética , Fatores Celulares Derivados do Hospedeiro/metabolismo , Receptores CCR5/genética , Argentina , Western Blotting , Contagem de Linfócito CD4 , Progressão da Doença , Haplótipos/genética , Humanos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Carga ViralRESUMO
OBJECTIVE: Our objective was to estimate primary resistance in an urban setting in a developing country characterized by high antiretroviral (ARV) coverage over the diagnosed population and also by an important proportion of undiagnosed individuals, in order to determine whether any change in primary resistance occurred in the past five years. DESIGN: We carried out a multi-site resistance surveillance study according to WHO HIV resistance guidelines, using a weighted sampling technique based on annual HIV case reports per site. METHODS: Blood samples were collected from 197 drug-naive HIV-1-infected individuals diagnosed between March 2010 and August 2011 at 20 HIV voluntary counselling and testing centres in Buenos Aires. Clinical records of enrolled patients at the time of diagnosis were compiled. Viral load and CD4 counts were performed on all samples. The pol gene was sequenced and the resistance profile determined. Phylogenetic analysis was performed by neighbour-joining (NJ) trees and bootscanning analysis. RESULTS: We found that 12 (7.9%) of the 152 successfully sequenced samples harboured primary resistance mutations, of which K103N and G190A were the most prevalent. Non-nucleoside reverse transcriptase inhibitors (NNRTI) resistance mutations were largely the most prevalent (5.9%), accounting for 75% of all primary resistance and exhibiting a significant increase (p=0.0072) in prevalence during the past 10 years as compared to our previous study performed in 1997-2000 and in 2003-2005. Nucleoside reverse transcriptase inhibitor (NRTI) and protease inhibitor primary resistance were low and similar to the one previously reported. CONCLUSIONS: Levels of primary NNRTI resistance in Buenos Aires appear to be increasing in the context of a sustained ARV coverage and a high proportion of undiagnosed HIV-positive individuals.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Adulto , Fármacos Anti-HIV/farmacologia , Argentina/epidemiologia , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , HIV-1/isolamento & purificação , Humanos , Incidência , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Análise de Sequência de DNA , População Urbana , Adulto Jovem , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genéticaRESUMO
BACKGROUND: In HIV infection, initiation of treatment is associated with improved clinical outcom and reduced rate of sexual transmission. However, difficulty in detecting infection in early stages impairs those benefits. We determined the minimum testing rate that maximizes benefits derived from early diagnosis. METHODS: We developed a mathematical model of HIV infection, diagnosis and treatment that allows studying both diagnosed and undiagnosed populations, as well as determining the impact of modifying time to diagnosis and testing rates. The model's external consistency was assessed by estimating time to AIDS and death in absence of treatment as well as by estimating age-dependent mortality rates during treatment, and comparing them with data previously reported from CASCADE and DHCS cohorts. RESULTS: In our model, life expectancy of patients diagnosed before 8 years post infection is the same as HIV-negative population. After this time point, age at death is significantly dependent on diagnosis delay but initiation of treatment increases life expectancy to similar levels as HIV-negative population. Early mortality during HAART is dependent on treatment CD4 threshold until 6 years post infection and becomes dependent on diagnosis delay after 6 years post infection. By modifying testing rates, we estimate that an annual testing rate of 20% leads to diagnosis of 90% of infected individuals within the first 8.2 years of infection and that current testing rate in middle-high income settings stands close to 10%. In addition, many differences between low-income and middle-high incomes can be predicted by solely modifying the diagnosis delay. CONCLUSIONS: To increase testing rate of undiagnosed HIV population by two-fold in middle-high income settings will minimize early mortality during initiation of treatment and global mortality rate as well as maximize life expectancy. Our results highlight the impact of achieving early diagnosis and the importance of strongly work on improving HIV testing rates.
Assuntos
Infecções por HIV/diagnóstico , Infecções por HIV/terapia , Adulto , Contagem de Linfócito CD4 , Simulação por Computador , Diagnóstico Precoce , HIV/isolamento & purificação , Infecções por HIV/mortalidade , Humanos , Expectativa de Vida , Pessoa de Meia-Idade , Modelos Biológicos , Taxa de Sobrevida , Resultado do Tratamento , Adulto JovemRESUMO
We studied drug resistance mutations (DRMs) in 2623 pol sequences. Out of 94,828 amino acid substitutions that were detected, 8749 corresponded to nucleoside reverse transcriptase inhibitor (NRTI), 3765 to nonnucleoside reverse transcriptase inhibitor (NNRTI), and 7141 to protease inhibitor (PI) resistance-associated mutations. The most common DRMs were L10I, I54V, L90M, V82A, A71V, L10V, M46I, M184V, M41L, T215Y, D67N, L210W, K70R, N348I, V118I, K103N, Y181C, G190A, K101E, V108I, L100I, V90I, K101Q, and A98G. As expected, DRMs frequencies depended on viral genotype. The amounts of NRTI and PI resistance mutations among B and BF sequences from children were higher than among sequences from adults. The frequencies of PI and NRTI resistance mutations among B and BF sequences from adult men were higher than among sequences from women. Some of these observations can be explained in light of the available epidemiological information, but some cannot, indicating that further studies are needed to understand the antiretroviral resistance epidemics in Argentina.
Assuntos
Antirretrovirais/farmacologia , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , HIV/genética , Mutação , Inibidores da Transcriptase Reversa/farmacologia , Adolescente , Adulto , Sequência de Aminoácidos , Antirretrovirais/uso terapêutico , Argentina , Criança , Pré-Escolar , Feminino , Identidade de Gênero , HIV/efeitos dos fármacos , Infecções por HIV/virologia , Humanos , Lactente , Masculino , Inibidores da Transcriptase Reversa/uso terapêuticoRESUMO
HIV-1 epidemics in South America are believed to have originated in part from the subtype B epidemic initiated in the Caribbean/North America region. However, circulation of BF recombinants in similar proportions was extensively reported. Information currently shows that many BF recombinants share a recombination structure similar to that found in the CRF12_BF. In the present study, analyzing a set of 405 HIV sequences, we identified the most likely origin of the BF epidemic in an early event of recombination. We found that the subtype B epidemics in South America analyzed in the present study were initiated by a founder event that occurred in the early 1970s, a few years after the introduction of these strains in the Americas. Regarding the F/BF recombinant epidemics, by analyzing a subtype F genomic segment within the viral gene gag present in the majority of the BF recombinants, we found evidence of a geographic divergence very soon after the introduction of subtype F strains in South America. Moreover, through analysis of a subtype B segment present in all the CRF12_BF-like recombination structure, we estimated the circulation of the subtype B strain that gave rise to that recombinant structure around the same time period estimated for the introduction of subtype F strains. The HIV epidemics in South America were initiated in part through a founder event driven by subtype B strains coming from the previously established epidemic in the north of the continent. A second introduction driven by subtype F strains is likely to have encountered the incipient subtype B epidemic that soon after their arrival recombined with them, originating the BF epidemic in the region. These results may explain why in South America the majority of F sequences are found as BF recombinants.
Assuntos
Evolução Molecular , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , Recombinação Genética , Análise por Conglomerados , Genoma Viral , Genótipo , HIV-1/isolamento & purificação , Humanos , Epidemiologia Molecular , Filogenia , Análise de Sequência de DNA , América do Sul/epidemiologia , Fatores de TempoRESUMO
In Argentina, HIV diagnosis is reached by voluntary testing or symptom-based case findings. However, because of the high proportion of infected individuals unaware of their serologic status new strategies are required. In this article we show how a mathematic model predicts the impact of expanding HIV testing in Argentina. The model is based on time-dependent Markov matrixes and applies parameters-dependent transition-probabilities obtained from both national and international cohort studies. Outputs include time on clinical stages and therapy regime, CD4-count, viral-load, infection-state and age; mortality rates and proportion of unidentified infection at a population-level. Simulations were performed for current testing strategy and for a theoretical scenario with earlier diagnosis. We show how our prediction suggests that diagnosis before onset of symptoms would increase life expectancy by 10.7 years. Also, we show how a reduction of time to diagnosis to 5 or less years from infection would reduce mortality rates in the first year of HAART from 7.6% to 2.1%, the proportion of unrecognized infection from 43.2% to 23.8% and the proportion of individuals with unaware infection needing treatment from 12% to 0.2%. Based on this prediction we stress the importance of implementing health policies aimed at detecting HIV infection in early stages in Argentina.
Assuntos
Infecções por HIV/diagnóstico , Expectativa de Vida , Terapia Antirretroviral de Alta Atividade , Argentina , Diagnóstico Tardio/efeitos adversos , Diagnóstico Precoce , Infecções por HIV/mortalidade , Humanos , Cadeias de Markov , Taxa de Sobrevida , Fatores de TempoRESUMO
Jujuy province, in Northwest Argentina, is known to be endemic for HTLV-1 infection. Moreover, foci of HTLV-1 associated pathologies have also been described in this region. To gain an insight into the current situation of HTLV-1/2 in this endemic area, a seroprevalence and phylogenetic study was performed among a Kolla community from Abra Pampa city and surroundings. Out of 112 individuals, 11 (9.8%) were confirmed as HTLV-1 positive and no HTLV-2 infection was detected. The phylogenetic analysis of the LTR region showed that all the HTLV-1 sequences belonged to the Cosmopolitan subtype a/transcontinental subgroup A, and were closely related to reference sequences from Peru, Argentina, and the South of Brazil (P = 0.82). Considering the cultural and historical features of this community and in spite of the mandatory detection of anti-HTLV-1/2 antibodies in blood banks since 2005, it would be important to implement new public health measures focused on decreasing HTLV-1 transmission in this endemic area.
Assuntos
Doenças Endêmicas , Infecções por HTLV-I/etnologia , Infecções por HTLV-I/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Indígenas Sul-Americanos , Adulto , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Argentina/epidemiologia , Argentina/etnologia , Feminino , Genótipo , Infecções por HTLV-I/virologia , Infecções por HTLV-II/epidemiologia , Infecções por HTLV-II/etnologia , Infecções por HTLV-II/virologia , Vírus Linfotrópico T Tipo 1 Humano/classificação , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Vírus Linfotrópico T Tipo 2 Humano/classificação , Vírus Linfotrópico T Tipo 2 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/imunologia , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Análise de Sequência de DNA , Estudos SoroepidemiológicosRESUMO
The South American HIV-1 epidemic is characterized by the co-circulation of subtype B and BF recombinant variants. Together with the B and BF genotypes, HIV-1 subtype C (HIV-1C), F1, and several other recombinants have been reported. The epidemiological significance and immune correlates of these "non-B-non-BF" strains circulating in South America are still uncertain and therefore are increasingly attracting the interest of the scientific community. In this study, the South American HIV-1C epidemic was studied using new technologies for the phylogenetic analysis of large datasets. Our results indicate that there is a major clade encompassing most of the South American HIV-1C strains. These analyses also agreed that some strains do not group inside this major clade, suggesting that there could be HIV-1C sequences of different origins circulating in South America. Others have proposed different hypotheses about the origins of HIV-1C strains from South America. This study shows that an exact single origin cannot be determined, a fact that could be attributed to sampling problems, phylogenetic uncertainty, and the shortage of historical and epidemiological data. Currently, the reported data indicate that HIV-1C strains were introduced in Brazil and afterward spread to other regions of South America. By using character optimization on the obtained phylogenetic trees, we observed that Argentina could also be a point in which the HIV-1C epidemic entered South America.
Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , Análise por Conglomerados , HIV-1/isolamento & purificação , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência , América do Sul/epidemiologiaRESUMO
Detection of HIV proteins and/or nucleic acids is necessary for the diagnosis of perinatal HIV infection. Despite its low sensitivity, detection of p24 antigen in plasma is a simple and economic method for the diagnosis of HIV in exposed children. The aim of this study was to improve the sensitivity of detection of p24 using centrifugation of plasma. Forty-seven selected stored samples from 37 children (23 infected, 14 uninfected, median age of 137 days) were examined. Plasma samples (volume 0.3-1.5 ml) were defrosted, centrifuged at 23,500 x g at 4 degrees C for 60 min and determination of p24 was carried out in the resuspended pellet (0.12 ml). In 32 plasma samples from infected children, p24 was found originally in 6 (18.7%) and resulted positive in 24 (75%) pellets. When only one sample per child was considered, sensitivity was significantly higher in pellets, 3/23 uncentrifuged plasma samples and 15/23 pellets (McNemar Test, p<0.001). Specificity was 100%. The absorbance/cut-off ratio was always higher in the pellets from positive children (p=0.028). Plasma samples with volumes of 1 ml or more achieved a higher sensitivity (91.7% vs. 36.4%, p=0.009). Centrifugation of plasma samples prior to determination of p24 in pediatric patients resulted in a significant increase in sensitivity.
Assuntos
Centrifugação , Proteína do Núcleo p24 do HIV/sangue , Infecções por HIV/diagnóstico , HIV-1/isolamento & purificação , Doenças do Recém-Nascido/virologia , Plasma/virologia , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Mães , Sensibilidade e Especificidade , Adulto JovemRESUMO
Mother-to-child transmission (MTCT) of human immunodeficiency virus type 1 (HIV-1) as described for women with an established infection is, in most cases, associated with the transmission of few maternal variants. This study analysed virus variability in four cases of maternal primary infection occurring during pregnancy and/or breastfeeding. Estimated time of seroconversion was at 4 months of pregnancy for one woman (early seroconversion) and during the last months of pregnancy and/or breastfeeding for the remaining three (late seroconversion). The C2V3 envelope region was analysed in samples of mother-child pairs by molecular cloning and sequencing. Comparisons of nucleotide and amino acid sequences as well as phylogenetic analysis were performed. The results showed low variability in the virus population of both mother and child. Maximum-likelihood analysis showed that, in the early pregnancy seroconversion case, a minor viral variant with further evolution in the child was transmitted, which could indicate a selection event in MTCT or a stochastic event, whereas in the late seroconversion cases, the mother's and child's sequences were intermingled, which is compatible with the transmission of multiple viral variants from the mother's major population. These results could be explained by the less pronounced selective pressure exerted by the immune system in the early stages of the mother's infection, which could play a role in MTCT of HIV-1.
Assuntos
Aleitamento Materno/efeitos adversos , Infecções por HIV/transmissão , HIV-1/genética , Transmissão Vertical de Doenças Infecciosas , Leite Humano/virologia , Complicações na Gravidez/virologia , Sequência de Aminoácidos , Primers do DNA , Feminino , HIV-1/classificação , HIV-1/patogenicidade , Humanos , Lactente , Recém-Nascido , Dados de Sequência Molecular , Filogenia , Gravidez , Seleção Genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Proteínas do Envelope Viral/genéticaRESUMO
BACKGROUND: Cytotoxic T-Lymphocyte (CTL) response drives the evolution of HIV-1 at a host-level by selecting HLA-restricted escape mutations. Dissecting the dynamics of these escape mutations at a population-level would help to understand how HLA-mediated selection drives the evolution of HIV-1. METHODOLOGY/PRINCIPAL FINDINGS: We undertook a study of the dynamics of HIV-1 CTL-escape mutations by analyzing through statistical approaches and phylogenetic methods the viral gene gag sequenced in plasma samples collected between the years 1987 and 2006 from 302 drug-naïve HIV-positive patients. By applying logistic regression models and after performing correction for multiple test, we identified 22 potential CTL-escape mutations (p-value<0.05; q-value<0.2); 10 of these associations were confirmed in samples biologically independent by a Bayesian Markov Chain Monte-Carlo method. Analyzing their prevalence back in time we found that escape mutations that are the consensus residue in samples collected after 2003 have actually significantly increased in time in one of either B or F subtype until becoming the most frequent residue, while dominating the other viral subtype. Their estimated prevalence in the viral subtype they did not dominate was lower than 30% for the majority of samples collected at the end of the 80's. In addition, when screening the entire viral region, we found that the 75% of positions significantly changing in time (p<0.05) were located within known CTL epitopes. CONCLUSIONS: Across HIV Gag protein, the rise of polymorphisms from independent origin during the last twenty years of epidemic in our setting was related to an association with an HLA allele. The fact that these mutations accumulated in one of either B or F subtypes have also dominated the other subtype shows how this selection might be causing a convergence of viral subtypes to variants which are more likely to evade the immune response of the population where they circulate.
Assuntos
HIV-1/genética , Antígenos HLA/imunologia , Mutação , Seleção Genética , Antígenos Virais/genética , Evolução Biológica , Epitopos/genética , Produtos do Gene gag/genética , Produtos do Gene gag/imunologia , HIV-1/imunologia , Antígenos HLA-B/imunologia , Humanos , Imunidade , Modelos Estatísticos , Linfócitos T Citotóxicos/imunologiaRESUMO
HTLV-1 Cosmopolitan subtype Transcontinental subgroup A has been described among aboriginal communities from the northwest endemic area of Argentina. Moreover, Transcontinental subgroup A and the Japanese subgroup B were reported among blood donors from the nonendemic central region of the country. We carried out the first HTLV-1 phylogenetic study in individuals residing in Buenos Aires capital city. Phylogenetic analysis performed on the LTR region showed that all 44 new strains clustered within the Cosmopolitan subtype, with 42 (95.4%) belonging to Transcontinental subgroup A. Of them, 20 (45.5%) strains grouped in the large Latin American cluster and 4 (9.1%) in the small Latin American cluster. The majority of them belonged to individuals of nonblack origin, grouped with Amerindian strains. Three (6.8%) were closely related to South African references and two monophyletic clusters including only HIV/HTLV-1 coinfected individuals were observed. Interestingly, two (4.5%) new sequences (divergent strains) branched off from all five known Cosmopolitan subgroups in a well-supported clade. In summary, these findings show that HTLV-1 Cosmopolitan subtype Transcontinental subgroup A is infecting residents of Buenos Aires, a nonendemic area of Argentina, and confirm the introduction of divergent strains in the country.
Assuntos
Infecções por HTLV-I/epidemiologia , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/classificação , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Adulto , Idoso , Argentina/epidemiologia , Análise por Conglomerados , Feminino , Genoma Viral , Genótipo , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Gestantes , Análise de Sequência de DNA , Homologia de Sequência , Sequências Repetidas Terminais/genética , População UrbanaRESUMO
To perform a diversity surveillance study we characterized viral subtypes among newly diagnosed individuals in Buenos Aires city. Plasma samples were collected from 322 drug-naive newly diagnosed HIV-1 individuals attending two voluntary counseling and testing centers. Sequences of pol and vpu genes were obtained from 283 samples and viral subtype was characterized by Neighbor-joining trees and Bootscanning analysis. BF recombinants were found in 56.9% followed by subtype B strains (39.2%). CRF12_BF structure was found in 27% of BF while another 27% had that structure only in one of both genes analyzed. Unusual non-B-non-BF strains were found in 3.9% (11/283). They were further analyzed by database searching and maximum likelihood trees in order to track their origin. Two subtype C sequences were found to be related to South American isolates while another two subtype C sequences and the subtype C segment of a BC recombinant were found to be related to isolates from Senegal. We also identified the CRF16_A2D previously found in Argentina and the CRF06_cpx commonly prevalent in Africa. The B segment of a BD recombinant was also found to be related to the Argentinean Bs suggesting a recombination between an African and a local strain. We also found a BK and two BA recombinants. In conclusion, CRF16_A2D and a new line of subtype C (of Senegalese origin) seem to be successfully established and are now spreading in Buenos Aires. BF recombinants keep recombining with local strains losing the CRF12_BF structure. Altogether they are changing the diversity of HIV in Argentina.
Assuntos
Variação Genética , Infecções por HIV/virologia , HIV-1/genética , Vigilância da População , Adolescente , Adulto , Argentina/epidemiologia , Feminino , Infecções por HIV/epidemiologia , HIV-1/classificação , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , FilogeniaRESUMO
OBJECTIVE: Our objective was to estimate primary resistance in an urban setting in a developing country with a long history of antiretroviral delivery and high coverage levels. DESIGN: We carried out a resistance surveillance study according to WHO HIV-Resistance Guidelines. METHODS: Blood samples were collected from 323 drug-naive HIV-1 infected individuals diagnosed at two HIV voluntary counselling and testing centers in Buenos Aires. Viral-load, CD4 cell counts and detuned assays were performed on all samples. The pol gene was sequenced and the resistance profile determined. Phylogenetic analysis was performed by neighbor-joining trees and bootscanning analysis. RESULTS: We found that 12 (4.2%) of the 284 samples sequenced harbored primary resistance mutations, of which K103N, M41L and V108I were most prevalent. Phylogenetic analysis revealed evidence for the transmission of the K103N mutation among the drug-naive population. The proportion of recent infections identified by the detuned assay was 10.1%. CONCLUSIONS: Levels of primary resistance in Buenos Aires are still low, despite a long history of ARV delivery and high coverage levels.
Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/epidemiologia , HIV-1/efeitos dos fármacos , Adulto , Argentina/epidemiologia , Países em Desenvolvimento , Farmacorresistência Viral/genética , Feminino , Genes Virais/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , HIV-1/genética , Humanos , Masculino , Mutação , Vigilância da População/métodos , Inibidores da Transcriptase Reversa/uso terapêutico , Medição de Risco/métodos , Saúde da População UrbanaRESUMO
To monitor HIV-1 diversity in Argentina, a phylogenetic-based analysis of HIV-1 partial pol sequences obtained for resistance testing in 587 treatment failure patients was performed in Buenos Aires city between 2001 and 2003. HIV-1 RNA was isolated from plasma samples and partial pol fragments amplified by RT-PCR. Sequences were obtained by automated sequencing. Phylogenetic analysis was performed and recombination patterns characterized. A total of 299 sequences grouped into clade B (50.94%) and 284 were B/F recombinants (48.38%). Four sequences were grouped into clades A, C, and F (0.68%). The clade C sample, 96105, was found to be a BC recombinant and samples 103396 and 104575 showed the same mosaic pattern with Kisii5009 from Kenya and 97KR004 from Korea, previously described as A2D recombinants. With the presence of two full-length genomes, one from Kenya and one from Korea, and now two partial genomes from Argentina, this recombinant is designated CRF16_A2D. Its presence on three continents shows that CRF16_A2D has a global distribution.