Outbreak of Trypanosoma evansi in the Brazilian Pantanal. A financial analysis

Abstract

The Brazilian Pantanal is a seasonal flood plain of about 138,000 km2 located in the center of South America. Extensive cattle ranching is the most important economic activity controlling about 80% of the land. The Pantanal's approximately 1,100 ranches are populated with about 3 million head of cattle and 49,000 horses. Horses play a central role in the industry. Trypanosoma evansi, locally known as "Mal de Cadeiras," kills horses within about ten days and is endemic to the Pantanal. Using a partial farm budget approach, the financial impact of an outbreak of T. evansi was analyzed in nine ranches in the Brazilian Pantanal in 1994. Treatment, animal collection and diagnostic costs, animal mortality and risk estimates were used to assess the efficacy of curative and preventive treatments relative to the observed and expected disease losses. The infection of more than 750 horses and the subsequent death of more than 10% of them due to the disease represented an economic loss of more than US$38,000. Results indicate that from 27 to 91% of these losses could have been avoided through the timely and appropriate implementation of available treatment strategies.