Modelling the Economics of African Swine Fever Control Strategies in Nigerian Pig Production Systems

This study develops economic models of alternative African Swine Fever control strategies in Nigerian pig production systems, providing the decision-theoretic framework needed to guide policy investment in ASF control. African Swine Fever is the most economically devastating livestock disease in Nigeria's pig sector, causing total herd losses with no available vaccine. Policy options for ASF control range from movement restrictions and targeted depopulation to biosecurity investment and trade surveillance, but their relative cost-effectiveness in the Nigerian context has not been modelled. This study develops a stochastic epidemiological-economic simulation model integrating an ASF transmission model parameterised from Nigerian outbreak data with a farm-level economic impact model and policy intervention cost analysis. Outbreak data are collected from NAFDAC, LVDD, and state veterinary office records from 2015 to 2023. Monte Carlo simulation generates distributions of epidemic outcomes and economic losses under alternative control scenarios in three pig production system typologies (smallholder backyard, small commercial, and commercial indoor). Benefit-cost analysis evaluates stamping-out, movement restriction, enhanced surveillance, and biosecurity investment strategies. Findings reveal that ASF causes an estimated annual economic loss of 84 billion naira in Nigeria's pig sector. Enhanced biosecurity investment at the farm level shows the highest benefit-cost ratio of 8.4 across production system types. Targeted stamping-out with compensation is cost-effective in commercial systems but not in smallholder systems due to administrative costs. The study contributes an original Nigerian ASF economic model and recommends prioritised biosecurity investment programmes with farm-level subsidy components.

Keywords: African Swine Fever, economic modelling, Nigeria, pig production, biosecurity.