Epidemiological trends of leprosy and case detection delay in East Hararghe Zone, Ethiopia: A baseline survey

Objectives
Leprosy is a chronic infectious disease caused by Mycobacterium leprae and one of the world’s most neglected tropical diseases. The post-exposure prophylaxis for leprosy study (PEP4LEP) compares two integrated skin-screening approaches combined with single dose rifampicin administration to contacts of leprosy patients. The aim of this baseline survey was to describe the epidemiological trends of leprosy and estimate case detection delay in the Ethiopian study districts before the start of the intervention.

Methods
The study was conducted in three districts of East Hararghe zone, Oromia Region, Ethiopia. We applied descriptive retrospective study design to describe epidemiological trends of leprosy between 2010 and 2019. Fifty patients diagnosed in the six months prior to their inclusion in the study were interviewed to establish the case detection delay at baseline. The healthcare delivery system and National Leprosy Control Program are also described.

Results
Trends in the number of new leprosy patients detected decreased slightly over the past ten years, although the number of new child cases increased overall, suggesting ongoing transmission. The mean case detection delay was 22.4 months (95% CI: 18.6–26.3), while the median was 19.5 months. The mean patient and health system delay were 19.6 months (95% CI: 15.8–23.4) and 2.6 months (95% CI: 1.5–3.6), respectively.

Conclusion
Considerable leprosy case detection delays were found in the PEP4LEP study districts in Ethiopia. Efforts to reduce delay and interrupt the transmission should focus on integrating prevention and active case finding, contact tracing and providing post-exposure prophylaxis to contacts of leprosy patients.