Optimal timing of HIV home-based counselling and testing rounds in Western Kenya.

Introduction: Weaknesses in care programmes providing anti-retroviral therapy (ART) persist and are often instigated by late HIV diagnosis and poor linkage to care. We investigated the potential for a home-based counselling and testing (HBCT) campaign to be improved through the optimal timing and enhancement of testing rounds to generate greater health outcomes at minimum cost.

Methods: Using a mathematical model of HIV care calibrated to longitudinal data from The Academic Model Providing Access To Healthcare (AMPATH) in Kenya, we simulated HBCT campaigns between 2016 and 2036, assessing the impact and total cost of care for each, for a further 20 years.

Results: We find that simulating five equally spaced rounds averts 1.53 million disability-adjusted life-years (DALYs) at a cost of $1617 million. By altering the timing of HBCT rounds, a four-round campaign can produce greater impact for lower cost. With "front-loaded" rounds, the cost per DALY averted is reduced by 12% as fewer rounds are required ($937 vs. $1060). Furthermore, improvements to HBCT coverage and linkage to care avert over two million DALYs at a cost per DALY averted of $621 (41% less than the reference scenario).

Conclusions: Countries implementing HBCT can reduce costs by optimally timing rounds and generate greater health outcomes through improving linkage, coverage, and retention. Tailoring HBCT campaigns to individual settings can enhance patient outcomes for minimal cost.