Salazar Vizcaya, Luisa PaolaLuisa PaolaSalazar VizcayaKeiser, OliviaOliviaKeiser0000-0001-8191-2789Technau, KarlKarlTechnauDavies, Mary-AnnMary-AnnDaviesHaas, AndreasAndreasHaas0000-0002-4849-181XBlaser, NelloNelloBlaser0000-0001-9489-1657Cox, VivianVivianCoxEley, BrianBrianEleyRabie, HelenaHelenaRabieMoultrie, HarryHarryMoultrieGiddy, JanetJanetGiddyWood, RobinRobinWoodEgger, MatthiasMatthiasEgger0000-0001-7462-5132Estill, Janne Anton MarkusJanne Anton MarkusEstill2024-10-232024-10-232014-10-23https://boris-portal.unibe.ch/handle/20.500.12422/131027OBJECTIVES Many paediatric antiretroviral therapy (ART) programmes in Southern Africa rely on CD4⁺ to monitor ART. We assessed the benefit of replacing CD4⁺ by viral load monitoring. DESIGN A mathematical modelling study. METHODS A simulation model of HIV progression over 5 years in children on ART, parameterized by data from seven South African cohorts. We simulated treatment programmes with 6-monthly CD4⁺ or 6- or 12-monthly viral load monitoring. We compared mortality, second-line ART use, immunological failure and time spent on failing ART. In further analyses, we varied the rate of virological failure, and assumed that the rate is higher with CD4⁺ than with viral load monitoring. RESULTS About 7% of children were predicted to die within 5 years, independent of the monitoring strategy. Compared with CD4⁺ monitoring, 12-monthly viral load monitoring reduced the 5-year risk of immunological failure from 1.6 to 1.0% and the mean time spent on failing ART from 6.6 to 3.6 months; 1% of children with CD4⁺ compared with 12% with viral load monitoring switched to second-line ART. Differences became larger when assuming higher rates of virological failure. When assuming higher virological failure rates with CD4⁺ than with viral load monitoring, up to 4.2% of children with CD4⁺ compared with 1.5% with viral load monitoring experienced immunological failure; the mean time spent on failing ART was 27.3 months with CD4⁺ monitoring and 6.0 months with viral load monitoring. Conclusion: Viral load monitoring did not affect 5-year mortality, but reduced time on failing ART, improved immunological response and increased switching to second-line ART.en600 - Technology::610 - Medicine & health300 - Social sciences, sociology & anthropology::360 - Social problems & social servicesarticle10.7892/boris.655482539285710.1097/QAD.0000000000000446