Determinants of Virologic Failure and Prevalence of Resistance Mutations among Human Immunodeficiency Virus (HIV) - Infected Children and Adolescents Aged 18 Months to 18 Years on Antiretroviral Therapy at Livingstone Teaching Hospital, Zambia

Abstract

Virologic failure is a major challenge in the management of Human Immunodeficiency Virus (HIV) among children and adolescents on antiretroviral therapy (ART). This study aimed to identify the prevalence of virologic failure, identify its determinants, and describe the pattern of HIV drug resistance mutations among HIV-infected children and adolescents aged 18 months to 18 years receiving ART at Livingstone Teaching Hospital. A facility-based cross-sectional study was conducted among 418 children and adolescents living with HIV. Virologic failure was defined as a viral load of ≥1,000 copies/mL. Data on sociodemographic, socio-economic, and clinical characteristics were collected from medical records and patient interviews. Logistic regression analysis was used to identify factors associated with virologic failure. Genotypic resistance testing was performed among participants with virologic failure to assess resistance mutations.The prevalence of virologic failure was 19.14%. Poor adherence to ART was the strongest predictor of virologic failure, with affected participants having significantly higher odds of failure. Adolescents were more likely to experience virologic failure compared to younger children. Low caregiver income and food insecurity were also independently associated with virologic failure. Drug resistance analysis showed no major NRTI resistance mutations, while NNRTI resistance mutations were common, particularly the K103N mutation. Resistance to integrase strand transfer inhibitors was rare.In conclusion, virologic failure among children and adolescents at Livingstone Teaching Hospital was mainly driven by poor adherence and socio-economic vulnerability rather than widespread drug resistance. Strengthening adherence support, implementing adolescent-friendly HIV services, and integrating socio-economic and nutritional support into HIV care are critical to improving treatment outcomes in this population.