A Yield and Cost Comparison of TB Contact Investigation and Intensified Case Finding in Uganda

Abstract

ABSTRACTIntroductionResource constraints in LMICs limit TB contact investigation despite evidence its benefits outweigh costs, with increased efficiency when compared with intensified case finding (ICF). However, there is limited data on the yield and cost per TB case identified in low resource-settings. We compared the yield and cost per TB case identified for ICF and TB-CI in Uganda.MethodsA retrospective cohort study based on data from 12 Ugandan hospitals was done between April and September 2017. Two methods of TB case finding (i.e. ICF and TB-CI) were used. Regarding ICF, patients either self-reported their signs and symptoms or were prompted by health care workers, and those suspected to have TB were requested to produce a sputum sample. On the other hand, TB-CI was done by home-visiting and screening contacts of TB patients for TB; with those found with signs and symptoms requested to produce sputum samples for examination. TB yield was defined as the ratio of diagnoses to tests, and this was computed per method of diagnosis. The costs per TB case identified (medical, personnel, transportation and training) for each diagnosis method were computed using the activity-based approach, from the health care perspective. Cost data were analyzed using Windows Excel.Results454 index clients’ cases and 2,707 of their household contacts were investigated. Thirty-one per cent of contacts (840/2707) were found to be presumptive TB cases. A total of 7,685 tests were done, 6,967 for ICF and 718 for TB-CI. ICF had a yield of 18.62% (1297/6967) at a cost of USD $120.60 to diagnose a case of TB while TB-CI had a yield of 5.29% (38/718) at an average cost of USD $ 877.57 to diagnose a case of TB.ConclusionRegarding case-finding, the yield of TB-CI was four-times lower and seven-times costlier compared to ICF. These findings suggest that ICF can improve TB case detection at a low cost, particularly in high TB prevalent settings.