Clinton Health Access Initiative (CHAI), Mbabane, Swaziland. Center on Methods for Implementation and Prevention Science and Department of Biostatistics, Yale School of Public Health, New Haven, CT, USA. Departments of Epidemiology, Biostatistics, Nutrition and Global Health, Harvard T.H Chan School of Public Health, Boston, MA, USA. Clinton Health Access Initiative (CHAI), Boston, MA, USA. Eswatini National ART program (SNAP), Ministry of Health, Mbabane, Swaziland. Department of Nutrition, Harvard T.H Chan School of Public Health, Boston, MA, USA. Leiden University Medical Center, Leiden University, Leiden, the Netherlands. Amsterdam Institute for Social Science, University of Amsterdam, Amsterdam, the Netherlands. Children's Institute, University of Cape Town, Cape Town, South Africa. The South African Department of Science and Technology - National Research Foundation (DST-NRF) Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA), Stellenbosch University, Stellenbosch, South Africa. Center for Statistics, Hasselt University, Diepenbeek, Belgium. International Centre for Reproductive Health, Ghent University, Gent, Belgium. KU Leuven, Rega Institute for Medical Research, Leuven, Belgium. Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Stellenbosch, South Africa. Eswatini National Network of People Living with HIV (SWANNEPHA), Mbabane, Swaziland. SAfAIDS, Manzini, Swaziland. aidsfonds, Amsterdam, the Netherlands. Heidelberg Institute of Public Health, University of Heidelberg, Heidelberg, Germany. Department of Global Health and Population, Harvard T.H Chan School of Public Health, Boston, MA, USA. Directorate Office, Ministry of Health, Mbabane, Swaziland.