Geospatial and computational economic analyses for the occurrence prediction, economic impacts and prevention of highly pathogenic avian influenza subtype H5N1: case studies in the Red River delta of Vietnam

Abstract

Highly Pathogenic Avian Influenza (HPAI) subtype H5N1 poses severe threats to both animals and humans. This dissertation seeks to improve disease detection and prevention and evaluate the potential economic consequences to smallholder producers in the Red River Delta of Vietnam through a series of 3 essays. The first essay takes into account spatial and temporal occurrences of HPAI H5N1 by using a two-stage procedure: logistic regression modeling followed by Bayesian Kriging. The results demonstrated that higher average monthly temperatures and poultry density in combination with lower average monthly precipitation and humidity in low elevation areas, roughly from November to January and April to June, contribute to the higher occurrence of HPAI H5N1. Provinces near the Gulf of Tonkin, including Hai Phong, Hai Duong, Thai Binh, Nam Dinh and Ninh Binh are areas with higher probability of HPAI H5N1 occurrence. The second essay explores the expected economic impacts of HPAI H5N1 on smallholder duck producers. A conceptual model is developed to optimize the producer profit maximization decision and evaluate expected profits/losses of the producer in light of HPAI H5N1. The results suggest that in the case of no disease occurrence, the optimal length of a production cycle is 10 weeks when ducks reach the age of 8 weeks which yields an estimated maximum profit of US$ 805. However, if the disease occurs, the resulting economic losses could reach a level three times higher than the maximum profit. The third essay addresses the tradeoff between the current policy which implements an annual two-round vaccination program for the entire area of the Delta and an alternative policy which focuses more frequent vaccinations in high probability areas within the Delta. The study applies an ex-ante analysis framework for identifying focus areas for the alternative vaccination program and efficacy and cost analyses for the tradeoff between current and alternative policies. The ex-ante analysis identifies 1137 communes for the alternative vaccination program. The efficacy and cost analysis suggests that the alternative policy would be more successful in reducing the occurrence rate and vaccination costs as compared to the current policy.