Spatial and temporal risk mapping of human and porcine Taenia solium infections in Malawi: A systematic review and geostatistical approach

Taenia solium cycles between human definitive hosts and pigs as intermediate hosts, with humans occasionally becoming aberrant intermediate hosts, causing human cysticercosis (HCC) or neurocysticercosis (NCC) when the central nervous system is involved. Malawi is WHO-classified as endemic, but subnational distribution remains unmapped, limiting targeted control.

This study paired a systematic literature review (PROSPERO CRD42023411044) with geospatial risk mapping using Demographic and Health Survey and FAO pig density data to build endemicity maps for 2000–2016, supplemented by hospital NCC records and slaughterhouse PCC data across Agricultural Development Divisions (ADDs).

Only nine studies were found, mostly HCC case reports, reflecting scarce population-based data. Hospital records showed 38 NCC cases near two major hospitals, while PCC rates in slaughtered pigs varied widely by ADD, highest in Mzuzu (3.7/100 pig-years) and Salima (4.5/100 pig-years). Risk mapping revealed high-risk areas consistently concentrated in central and southern districts, with high pig density and poverty co-occurring nationally in 2000 but persisting mainly centrally by 2016.

Given sparse population-based evidence and the convergence of poverty, poor sanitation and high pig density in central and southern Malawi, these areas warrant urgent targeted study to inform T. solium control interventions.