Introduction: This study explores factors associated with virological detectability, and viral re-suppression after enhanced adherence counselling, in adults and children on antiretroviral therapy (ART) in Swaziland. Methods: This descriptive study used laboratory data from 7/5/2012 to 30/9/2013, which were linked with the national ART database to provide information on time on ART and CD4 count; information on enhanced adherence counselling was obtained from file review in health facilities. Multivariable logistic regression was used to explore the relationship between viral load, gender, age, time on ART, CD4 count and receiving (or not receiving) enhanced adherence counselling. Results: From 12,063 patients undergoing routine viral load monitoring, 1941 (16%) had detectable viral loads. Children were more likely to have detectable viral loads (AOR 2.6, 95%CI 1.5-4.5), as were adolescents (AOR 3.2, 95%CI 2.2-4.8), patients with last CD4<350 cells/μl (AOR 2.2, 95%CI 1.7-2.9) or WHO Stage 3/4 disease (AOR 1.3, 95%CI 1.1-1.6), and patients on ART for longer (AOR 1.1, 95%CI 1.1-1.2). At retesting, 450 (54% of those tested) showed viral re-suppression. Children were less likely to re-suppress (AOR 0.2, 95%CI 0.1-0.7), as were adolescents (AOR 0.3, 95%CI 0.2-0.8), those with initial viral load> 1000 copies/ml (AOR 0.3, 95%CI 0.1-0.7), and those with last CD4<350 cells/μl (AOR 0.4, 95%CI 0.2-0.7). Receiving (or not receiving) enhanced adherence counselling was not associated with likelihood of re-suppression. Conclusions: Children, adolescents and those with advanced disease were most likely to have high viral loads and least likely to achieve viral suppression at retesting; receiving adherence counselling was not associated with higher likelihood of viral suppression. Although the level of viral resistance was not quantified, this study suggests the need for ART treatment support that addresses the adherence problems of younger people; and to define the elements of optimal enhanced adherence support for patients of all ages with detectable viral loads.
