Monitoring viral load for the last mile: what will it cost?

By  Brooke Nichols  Sarah Girdwood  Thomas Crompton, Lynsey Stewart-Isherwood, Leigh Berrie, Dorman Chimhamhiwa, Crispin Moyo, John Kuehnle, Wendy Stevens  Sydney Rosen  |  | 

Routine viral load testing is the WHO-recommended method for monitoring HIV-infected patients on ART, and many countries are rapidly scaling up testing capacity at centralized laboratories. Providing testing access to the most remote populations and facilities (the “last mile”) is especially challenging. Using a geospatial optimization model, we estimated the incremental costs of accessing the most remote 20% of patients in Zambia by expanding the transportation network required to bring blood samples from ART clinics to centralized laboratories and return results to clinics.The model first optimized a sample transportation network (STN) that can transport 80% of anticipated sample
volumes to centralized viral load testing laboratories on a daily or weekly basis, in line with Zambia’s 2020 targets. Data incorporated into the model included the location and infrastructure of all health facilities providing ART, location of laboratories, measured distances and drive times between the two, expected future viral load demand by health facility, and local cost estimates. We then continued to expand the modelled STN in 5% increments until 100% of all samples could be collected.

Publication details

Journal of the International AIDS Society