Imperial College London


Faculty of MedicineSchool of Public Health

Professor of Mathematical Epidemiology



+44 (0)20 7594 3263mc.boily




LG26Norfolk PlaceSt Mary's Campus






BibTex format

author = {Maheu-Giroux, M and Tanser, F and Boily, MC and Pillay, D and Joseph, SA and Bärnighausen, E},
doi = {10.1097/QAD.0000000000001435},
journal = {AIDS},
pages = {1017--1024},
title = {Determinants of time from HIV infection to linkage-to-care in rural KwaZulu-Natal, South Africa},
url = {},
volume = {31},
year = {2017}

RIS format (EndNote, RefMan)

AB - Objective: To estimate time from HIV infection to linkage-to-care and its determinants.Linkage-to-care is usually assessed using the date of HIV diagnosis as the startingpoint for exposure time. However, timing of diagnosis is likely endogenous to linkage,leading to bias in linkage estimation.Design: We used longitudinal serosurveys from a large population-based HIV cohort inKwaZulu-Natal (2004-2013) to estimate time of HIV infection. We linked this data topatient records from a public-sector HIV treatment and care program to determine timefrom infection to linkage (defined using the date of the first CD4 count).Methods: We used Cox proportional-hazards models to estimate time from infection tolinkage and the effects of the following covariates on this time: gender, age, education,food security, socio-economic status, area of residence, distance to clinics, knowledgeof HIV status, and whether other household members have initiated ART.Results: We estimated that it would take an average of 4.9 years for 50% ofseroconverters to be linked to care (95% confidence intervals (CI): 4.2-5.7). Among allcohort members that were linked to care, the median CD4 count at linkage was 350cells/μL (95%CI: 330-380). Men and participants <30 years were found to have theslowest rates of linkage-to-care. Time to linkage became shorter over calendar time.Conclusions: Average time from HIV infection to linkage-to-care is long and needs tobe reduced to ensure that HIV treatment-as-prevention policies are effective. Targetedinterventions for men and young individuals have the largest potential to improve linkage rates
AU - Maheu-Giroux,M
AU - Tanser,F
AU - Boily,MC
AU - Pillay,D
AU - Joseph,SA
AU - Bärnighausen,E
DO - 10.1097/QAD.0000000000001435
EP - 1024
PY - 2017///
SN - 0269-9370
SP - 1017
TI - Determinants of time from HIV infection to linkage-to-care in rural KwaZulu-Natal, South Africa
UR -
UR -
VL - 31
ER -