Authors

J J Palmer¹;  ¹ Centre of African Studies, University of Edinburgh

Discussion

As the cost-effectiveness of active case detection declines, the contribution of passive case detection to syndromic surveillance is increasingly important for elimination of T. b. gambiense human African trypanosomiasis (HAT). Very little is known, however, about how a passive approach to detection works, which is essential for it to be optimised. Through interviews conducted with patients, family members and health workers (2008-2009), this study presents the passive case detection histories of 33 HAT patients in Nimule, South Sudan. Two main mechanisms underpinned successful detection, each of which was used by both health workers and patients: ‘clinical suspicion’, whereby HAT was the primary suspicion based on biomedical or local understandings of symptoms; and ‘opportunistic testing’, whereby HAT referral occurred during a process of ‘trying tests’ that were available. Lay people initiated HAT testing more often than health workers (20/33 cases). Opportunistic testing characterised a third of health worker referrals and over half of lay referrals and depended on knowledge of test availability. These findings highlighted not only a need for better HAT syndromic training of health staff but also the importance of informal processes such as ‘opportunism’ for case detection in this context. Each of these mechanisms could be targeted and evaluated by control programmes.