The Virological and Immunological Characteristics of the HIV-1-Infected Population in Brazil: From Initial Diagnosis to Impact of Antiretroviral Use

Abstract

BackgroundImmunological and virological status of HIV-infected individuals entering the Brazilian public system over time was analyzed. We evaluated the impact of ART on virological, immunological and antiretroviral resistance over time.MethodsCD4+ T cell counts, viral loads and genotypes from patients over 13 years old from 2001–2011 were analyzed according to demographic data. We compared groups using parametric t-tests and linear regression analysis in the R statistical software language.ResultsMean baseline CD4+ T cell counts varied from 348 (2003) to 389 (2009) and was higher among women (p = 1.1 x 10−8), lower in older patients (p< 1 x 10−8) and lower in less developed regions (p = 1.864 x 10−5). Percentage of treated patients with undetectable viral loads increased linearly from 46% (2001) to 77% (2011), was lower among women (p = 2.851 x 10−6), younger ages (p = 1 x 10−3), and in less developed regions (p = 1.782 x 10−4). NRTI acquired resistance was 86% in 2001–3 and decreased over time. NNRTI resistance increased from 2001-3(50%) to 2006–9 (60%), PI resistance decreased from 2001–3 (60%) to 2009 (40%), and 3-class resistance was stable over time around 25%. Subtype prevalence comprised B (75.3%), B/F recombinants (12.2%), C (5.7%), F (5.3%) and B/C recombinants (1.5%), with regional variations. Three-class resistance was 26.5% among Bs, 22.4% among Fs and 17.2% among Cs.ConclusionsHIV diagnosis occurs late, especially among elderly Brazilians. Younger individuals need special attention due to poor virological response to treatment. Antiretroviral Resistance profile is subtype related.

Antiretroviral therapy initiation within seven days of enrolment: outcomes and time to undetectable viral load among children at an urban HIV clinic in Uganda

“…However, we believe that our findings portray a realistic clinical picture amidst operational treatment challenges in health care facilities. Our findings further contribute to the body of evidence that consistently good adherence (≥95%) and WHO clinical stage at baseline influence the virological outcomes of patients [27, 35]. Findings seen in our study regarding the contribution of baseline weight on clinical improvement among HIV patients has also been shown elsewhere [37].…”

HIV-1 genetic diversity and antiretroviral drug resistance among individuals from Roraima state, northern Brazil

“…The prevalence of ADRM here detected in Roraima (28%) was relatively low compared to the higher levels of resistance to NRTI, NNRTI and/or PI (>80%) reported in other Brazilian states from all country regions [11–19]. It could be argued that most previous studies of ADRM conducted in Brazil analyzed populations of HIV-1-infected individuals failing ART and that the relative low rate of ADRM observed in Roraima may be explained by a low frequency of virological failure among treated patients.…”

Brazilian network for HIV Drug Resistance Surveillance (HIV‐BresNet): a survey of treatment‐naive individuals

“…This CRF was more present in the southern region; however, we encountered them throughout the central‐west and southeast regions as well. According to predictions using the Bayesian Markov chain Monte Carlo (MCMC) methods and the reversible‐jump MCMC method, HIV‐1 subtype B emerged in 1971, subtype F emerged in 1981, BF recombinants emerged in 1989, subtype C emerged in 1987 and BC recombinants emerged in 1992 . This study also predicted that the basic reproductive number of secondary infections ( R 0 = 5 year interval) is 2.4 for Brazilian subtype B strains, 2.3 for subtype F and 4.6 for subtype C, warning for the faster expansion of this latter in the Brazilian epidemics .…”

“…According to predictions using the Bayesian Markov chain Monte Carlo (MCMC) methods and the reversible‐jump MCMC method, HIV‐1 subtype B emerged in 1971, subtype F emerged in 1981, BF recombinants emerged in 1989, subtype C emerged in 1987 and BC recombinants emerged in 1992 . This study also predicted that the basic reproductive number of secondary infections ( R 0 = 5 year interval) is 2.4 for Brazilian subtype B strains, 2.3 for subtype F and 4.6 for subtype C, warning for the faster expansion of this latter in the Brazilian epidemics . It is also worth mentioning, that one study analysing phenotypic resistance in a limited number of samples from antiretroviral‐naive individuals in Brazil revealed that some subtype C strains presented phenotypic resistance no NRTIs and more frequently to NNRTIs without significant genotypic mutations, which suggests that the genotypic correlates of subtype C resistance might not yet be clearly defined, posing an additional problem related to the HIV‐1 genetic diversity .…”