The impact of migrant-inclusive policy on Botswana's universal HIV treatment program: a retrospective analysis of the national HIV treatment program data (2016-2022).

BACKGROUND: Botswana has made substantial progress toward the Joint United Nations Programme on Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) (UNAIDS) 95-95-95 targets. However, migrants were historically excluded from free antiretroviral therapy (ART). In December 2019, Botswana extended free HIV testing and treatment to migrants. Population-level data on ART coverage, viral load testing, and virologic suppression among migrants remain limited. Therefore, the study intends to assess the impact of including migrants in the national HIV treatment program by determining ART coverage, baseline cluster of differentiation 4 (CD4) cell counts at enrollment, and virologic outcomes before and after the policy.

METHODS: This is a retrospective longitudinal observational dataset of all people living with Human Immunodeficiency Virus (PLWH) enrolled in the national treatment program from 2016 to 2022, with citizen status documented and aged 18 + years. The dataset was classified into two categories of individuals enrolled on ART using enrollment year: pre-2019 (citizen-only policy) and post-2019 (migrant-inclusive policy). The baseline CD4 cell count at ART initiation was compared between pre- and post-2019 eras using a modified Poisson regression and linear regression, adjusted for age, sex, and facility, with a difference-in-differences (DiD) model to provide a controlled comparison. The virologic outcomes and mortality were evaluated using modified Poisson and Cox models, adjusted for age, sex, and baseline CD4 cell counts.

RESULTS: Among 87,063 PLWH, 40,165 had baseline CD4 cell count data, while 50,043 individuals had viral load (VL) data. Median baseline CD4 cell counts among migrants were 296 cells/μL and 300 cells/μL, pre-2019 and post-2019, respectively (no significant change; β = 1.8 cells/ mm3, 95% confidence interval [CI]: -14.0 to 17.6; p = 0.819). Advanced HIV disease at ART initiation (CD4 < 200 cells/μL) declined significantly from 22.9 to 17.7% (adjusted relative risk [aRR]: 0.76, 95% CI: 0.63-0.90; p = 0.002). Difference-in-differences models showed more favorable changes post-2019 among migrants vs. citizens in both continuous CD4 cell counts (interaction β = 54.2 cells/mm3, 95% CI: 37.7-70.6; p < 0.001) and advanced disease at initiation (interaction RR = 0.74, 95% CI: 0.62-0.89; p = 0.001). The VL measurement capture among migrants increased from 27.7 to 58.5% at 6 months, 31.1-66.1% at 12 months, 32.0-74.6% at 24 months, and 40.5-82.6% at 36 months (all adjusted RRs: 1.86-2.25; p < 0.001) after the policy shift. Observed virologic suppression (<400 copies/mL) remained high (≥94%) with no significant post-2019 change. Mortality was low and unchanged post-2019 (interaction adjusted hazard ratio [aHR] 1.99, 95% CI: 0.41-9.70; p = 0.393).

CONCLUSION: Extending Botswana's ART program to migrants reduced advanced HIV disease at initiation and significantly improved viral load monitoring and sustained viral suppression. Removing citizenship-based barriers reduces health inequities and supports epidemic control toward the UNAIDS 95-95-95 targets.