Barrow, Geoffrey; Hylton-Kong, Tina; Rodriguez, Nyra; Yamamura, H; Figueroa, J.Peter
Author Affiliation, Ana.
HIV-1 drug resistance in treatment naive, chronically infected patients in Jamaica
Date of Publication
Introduction In 2010, Jamaica had an estimated prevalence of 1.7% in the general population . HIV-1 subtype B has been identified as predominant [2, 3], being evident in up to 93% of cases . In 2004, a public access treatment programme was established . This was augmented in 2007 by the rapid expansion of antiretroviral therapy (ART) access . The provision of ART follows a public health approach with standardized treatment guidelines. The ART backbones include non-nucleoside reverse transcriptase inhibitors (NNRTIs), efavirenz and nevirapine, and ritonavir boosted protease inhibitors (PIs), lopinavir and atazanavir. One survey of 37 cases in Jamaica identified HIV drug resistance in 29% of treatment na´ve patients . In developed countries, reports have indicated an increasing prevalence of transmitted drug resistance (TDR) [7, 8]. One paper summarizing the temporal changes in TDR reported the United States as having the highest TDR prevalence at 12.9%, followed by Europe at 10.9% . In developing countries, TDR prevalence was reported as 2.4% in south/southeast Asia and 3.2% in sub-Saharan Africa . In Latin America reports range from 3.3% in Peru to 7.0% in Honduras . The purpose of this study was to investigate the prevalence of transmitted resistance among persons with established HIV-1 infection at The Comprehensive Health Centre, the largest government sponsored HIV treatment site located in Kingston, Jamaica. The total HIV-1 population at this site was estimated to be 3,000 patients. A post-hoc analysis of applying the WHO/PAHO protocols for HIVDR surveillance is also presented. Methodology A cross-sectional study of antiretroviral na´ve patients and patients exposed to short-term therapy for prevention of mother-to-child transmission (pMTCT) was conducted. HIV-1 diagnosis was made based on a screening rapid HIV-1/2 antibody test and confirmed with western blot testing. Patients included in the study were 18 years of age or older, had documented HIV-1 infection and were able to provide written consent. All HIV-1 treatment na´ve patients presenting consecutively at the treatment site were approached for recruitment into the study. Study accrual was completed over a 4 month period between January and April 2011. Quantitative data was garnered via a structured data collection questionnaire and a review of patient files. Whole blood samples were collected in EDTA tubes from each participant. Processing included centrifugation and storage of the resulting plasma at -80 degrees Celsius on the same day of collection. The samples were subsequently shipped on dry ice to Ponce University in Puerto Rico where viral load assessments, sequencing of the reverse transcriptase and protease regions of the HIV-1 pol gene were performed, using the World Health Organization (WHO) HIV ResNetę protocol. Additionally, phenotypic analysis was performed utilising the VIRCO« virtual phenotype method. Resistance mutations were interpreted using the Stanford HIV Database algorithm  and the WHO HIVDR surveillance mutations (SDRM) . The calculation of the sample size of 100 participants was powered (a = 0.05) at a 95% confidence level to detect a transmitted resistance rate of 5%. All data was analysed using SPSS version 17.0 statistical software for Windows (SPSS, Chicago, IL, USA). Frequencies were used to describe categorical variables. Means with 95% confidence intervals were used to describe clinical and demographic data that are distributed normally and medians with inter-quartile ranges for those that were not. Comparisons were analysed using Chi-squared and Students t-tests with a significance level of less than 0.05. Ethical approval for this study was provided by the University of the West Indies, Faculty of Medicine Ethics Board, Mona, Jamaica. All participants provided informed written consent prior to inclusion in the study. Results In this study, 103 treatment na´ve HIV-1 infected participants were identified, 64 female and 39 male. The mean age at the time of the study was 37.3 years (95% C.I. 35.0 - 39.5), while the mean age at HIV-1 diagnosis was 34.5 years (95% C.I. 32.3 - 36.7) and ranged from 15 to 66 years (Table 1). The median time since HIV-1 diagnosis was 13.5 months (Inter Quartile Range 2.0 ľ 52.0) with 23/103 (22.3%) participants being diagnosed in the same month as study enrolment. HIV acquisition through sexual contact was reported by 98/103 (95.1%) participants, among whom 96/98 (98.0%) reported heterosexual contact and 2/98 (2.0%) male homosexual contact. The median time from last sexual exposure was reported at 12 days (IQR 4 - 31) with 56/73 (76.7%) reporting condom use during this exposure (Table 1).....