Financial analysis of brucellosis control for small-scale goat farming in the Bajío region, Mexico.

Brucellosis is an endemic disease in small-scale goat husbandry systems in Mexico. It is a zoonosis and the economic consequences can be large, although estimates are not available for the Mexican goat sector. Our objective was to conduct a financial analysis of brucellosis control in a prominent dairy goat production area of the Bajío region, Mexico. We used three models: (1) a brucellosis transmission model at village flock level (n=1000 head), (2) a flock growth model at smallholder flock level (n=23 head) using output of model 1 and (3) cost-benefit analysis of several brucellosis control scenarios based on output of model 2. Scenarios consisted of test-and-slaughter or vaccination or a combination of both compared to the base situation (no control). The average net present values (NPV) of using vaccination over a 5-year period was 3.8 US$ (90% CI: 1.3-6.6) and 20 US$ (90% CI: 11.3-28.6) over a 10-year period per goat. The average benefit-cost ratios over a 5-year period and 10-year period were 4.3 US$ (90% CI: 2.2-6.9) and 12.3 US$ (90% CI: 7.5-17.3) per goat, respectively. For the total dairy goat population (38,462 head) of the study area (the Bajío of Jalisco and Michoacán) the NPV's over a 5-year and 10-year period were 0.15 million US$ and 0.8 million US$. However, brucellosis prevalence was predicted to remain relatively high at about 12%. Control scenarios with test-and-slaughter predicted to reduce brucellosis prevalence to less than 3%, but this produced a negative NPV over a 5-year period ranging from -31.6 to -11.1 US$ and from -31.1 to 7.5 US$ over a 10-year period. A brucellosis control campaign based on vaccination with full coverage is economically profitable for the goat dairy sector of the region although smallholders would need financial support in case test-and-slaughter is applied to reduce the prevalence more quickly.