Brucellosis Control and eradication programs

An important problem encountered by the veterinary authorities in countries affected by brucellosis is to select the sanitary strategy to be applied against the disease. Adequate organization of veterinary services is, without any doubt, the most important element to be taken into consideration by decision-makers previous to any potential selection of a sanitary programme. The economic costs of eradication programs are very important, and financial resources should be allocated to support the programs as an essential requisite prior to the selection of any eradication strategy. The adequate organization and involvement of shepherds is also another essential requisite for success in the implementation of even the simplest control strategy based on mass vaccination. Once the professional organization and the economic resources are fully adequate, the epidemiological unit of intervention should be defined. Whenever the collective prevalence (percentage of infected flocks) in this unit be uniformly very low (always less than 1% of flocks infected), a strategy based on a test and slaughter programme and a ban on vaccination could be applied to eradicate the disease in the short to medium term in that particular epidemiological unit. In the case where prevalence is uniformly moderate, a combined eradication programme based on the simultaneous application of vaccination in young replacements and a test and slaughter in adult animals could be recommended to eradicate the disease in the medium to long term. However, when the disease is highly prevalent (more than 10% of flocks are infected), even though the professional organization and the economic resources be fully adequate, the mass vaccination of all animals is the only reasonable strategy that can be applied to control the disease.