Prevalence of human immunodeficiency virus drug resistance and factors associated with high viral load among adolescents on antiretroviral therapy in Dar Es Salaam, Tanzania.

Background: Resistance to antiretrovirals against human immunodeficiency virus (HIV) poses a threat to zero transmission of HIV by 2030. Few studies have been conducted on HIV drug resistance (HIVDR) mutations targeting adolescents. We determined the prevalence, pattern of HIVDR mutations, and factors associated with unsuppressed HIV viral load among adolescents on antiretroviral therapy (ART).

Methods: From March to June 2020, we conducted a cross-sectional study at the Infectious Disease Clinic in Dar es Salaam, Tanzania. HIV-1 viral load was tested using m2000rt Real-Time HIV-1 assay. A sample with a viral load equal or more than 1,000 copies/ml was tested for HIVDR mutations. We determined the factors associated with unsuppressed viral load using logistic regression. A -value less than 0.05 was considered significant.

Results: We enrolled 131 participants with a median age (interquartile range) of 15 (13-18) years. Of all, 24(18.3%) had a viral load above 1000 copies/ml. HIVDR mutations were found in 19/24(68.4%). Mutation to protease inhibitors, nucleotide reverse transcriptase inhibitors, and non-nucleoside reverse transcriptase inhibitors were 1(5.2%), 9(47.4%), and 11(57.9%), respectively. Non-antiretroviral therapy and orphanages were independently associated with unsuppressed viral load.

Conclusion: The prevalence of HIVDR and unsuppressed HIV viral load among adolescents are relatively high. The use of non-antiretroviral therapy and orphanage influenced the persistence of high viral load. Strategies for surveillance of HIVDR early warning signs should be devised among adolescents.