Confirmation of a hyperendemic focus of porcine cysticercosis in Northern Uganda: Prevalence and risk factor analysis

Background: Taenia solium (T. solium), a neglected zoonotic tapeworm transmitted between humans and pigs, is a leading cause of acquired epilepsy in endemic areas where it is propagated by poor sanitation and pig husbandry practices. The World Health Organisation (WHO) NTD roadmap 2021–2030, recommended that targeted control interventions need to be initiated, and intensified in T. solium hyperendemic areas. Geospatial risk maps have identified Northern Uganda as a potential hyperendemic area. This study aimed to validate these findings and provide contextual evidence to support design and implementation of targeted interventions to control the parasite.

Methods: A cross-sectional study was conducted in 2023 in four districts of northern Uganda. Blood samples were collected for serological analysis from 1049 pigs drawn from 714 households. Self-reported and observational data, and environmental variables from secondary sources were also collected. A subset of the seropositive pigs was dissected to confirm the presence of the parasite. The crude prevalence was adjusted for the test’s sensitivity (Se = 0.867) and specificity (Sp = 0.947). Risk factors for seropositivity were evaluated using generalized mixed-effects models run in both R and Stata statistical software.

Results: The prevalence of porcine cysticercosis in this area was 17.4% (15.1– 19.7; 95% CI). Pig level predictors of infection were pigs that were eight months or older (odds ratio (OR)=1.88; p = 0.001), and non-local breeds of the pig (OR=1.7; p = 0.01). Household-level risk factors included the use of borehole water, (OR=6.39; P = 0.001), free-roaming pigs (OR=1.92; p = 0.023), whilst the presence of a toilet in the compound was protective (OR=0.64, p = 0.05).

Conclusion: Our findings confirm that the study area is hyperendemic for T. solium infections, as the geospatial risk maps predicted. To achieve the targets laid out in the 2021–2030 WHO roadmap for control of NTDs, this region requires intensified targeted control interventions, preferably targeting both human and porcine hosts using the One Health approach.