Prevalence of transmitted HIV‐1 antiretroviral resistance among patients initiating antiretroviral therapy in Brazil: a surveillance study using dried blood spots

Abstract

IntroductionIn Brazil, the use of antiretrovirals is widespread: more than 260,000 individuals are currently undergoing treatment. We conducted a survey targeting antiretroviral-naïve individuals who were initiating antiretroviral therapy (ART) according to local guidelines. This survey covered five Brazilian regions.MethodsThe HIV Threshold Survey methodology (HIV-THS) of the World Health Organization was utilized, and subjects were selected from seven highly populated cities representative of all Brazilian macro-regions. Dried blood spots (DBS) were collected on SS903 collection cards and were transported by regular mail at room temperature to a single central laboratory for genotyping.ResultsWe analysed samples from 329 individuals initiating highly active antiretroviral therapy (HAART), 39 (11.8%) of whom were harbouring transmitted drug resistance (TDR). The mean CD4+ T cell count was 253 cells/µL, and the mean viral load was 142,044 copies/mL. The regional prevalence of resistance was 17.0% in the Northeast, 12.8% in the Southeast, 10.6% in the Central region, 8.5% in the North and 8.5% in the South. The inhibitor-specific TDR prevalence was 6.9% for nucleoside reverse transcriptase inhibitors, 4.9% for non-nucleoside reverse transcriptase inhibitors and 3.9% for protease inhibitors; 3.6% of individuals presented resistance to more than one class of inhibitors. Overall, there were trends towards higher prevalences of subtype C towards the South and subtype F towards the North. Of the DBS samples collected, 9.3% failed to provide reliable results.DiscussionWe identified variable TDR prevalence, ranging from intermediate to high levels, among individuals in whom HIV disease progressed, thus implying that resistance testing before initiating ART could be effective in Brazil. Our results also indicate that the use of DBS might be especially valuable for providing access to testing in resource-limited and remote settings.

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

“…These prevalences are similar to the ones previously described in Brazil, as seen in Figure . However, higher prevalence has occasionally been described in the cities of Salvador, located in the northeast region of Brazil (18.9% and 17.0%) and Santos , in the southeast region of Brazil (29.2% and 17.0%) . Our data is also consistent with other South American countries where mass treatments are provided.…”

HIV-1 Molecular Characterization and Transmitted Drug Resistance Prevalence among Treatment-Naïve Individuals

“…However, the TDR prevalence reported here is markedly lower than that described by De Moraes et al (17%), whose samples were collected in the same year as ours (2012) [12]. It is interesting to note that these authors included …”

Surveillance of HIV Transmitted Drug Resistance in Latin America and the Caribbean: A Systematic Review and Meta-Analysis

“…Surveys performed before or around 2005 showed low TDR prevalence (<5%) to any ARV class: 4.9% in the first HIVDR BResNet survey in 2001 including 13 centers across the country (n = 356) [ 59 ], and 1.4% in blood donors from the North, North-East and South-East Regions in 2000–2004 (n = 74) [ 60 ]. More recent surveys performed in mixed adult populations with HIV infection of unknown duration showed higher TDR levels to any ARV class: 5.2% in 2007 [ 61 ]; 6.6% in 2007–2008 [ 62 ]; 12.2% in 2007–2011 [ 63 ] and 11.8% in 2009–2010 [ 64 ]. Within these studies, three large national surveys performed at different time intervals show clear TDR trends in time: Brindeiro et al (2001, n = 356, including 13 centers across the country) reported 4.9% to any ARV class, 2.4% NRTI, 0.3% NNRTI, and 2.3% PI [ 59 ]; Inocencio et al (2007–2008, n = 210, including Sao Paulo, Rio de Janeiro, Salvador, Porto Alegre, Brasilia and Belem) 6.6% to any ARV class, 1.9% NRTI, 2.9% NNRTI, and 2.4% PI [ 62 ]; de Moraes-Soares et al (2009–2010, n = 329, including Manaus, Salvador, Brasilia, Rio de Janeiro, Santos, Porto Alegre, Itajaí) 11.8% to any ARV class, 6.9% NRTI, 4.9% NNRTI, and 3.9% PI [ 64 ].…”