The aim of an eradication program is not a ¿zero seropositivity¿ situation, but the absence of infection, given that seropositivity can occur after vaccination or YO9 infection . Criteria to declare a country or a region ¿officially free from brucellosis¿ have been laid down in international regulations such as in EU Directives and recommendations of the OIE. The epidemiology of brucellosis is complex and criteria other than test results are needed in order to guarantee the success of an eradication program (49). The S19 and Rev. 1 vaccines are still the cornerstones of control and eradication programs . In contrast, no vaccine is available against brucellosis in wildlife. It is striking to see that the ecology of infection remains so poorly understood. For example, scientists have speculated for decades whether brucellosis induces abortion in bison . Little is known about the pathology of B.suis biovar 2 in wild boars , and marine mammal brucellosis research is still in its infancy . Very little is known about brucellosis pathology in marine mammals or their zoonotic potential. Emphasis should be put on multidisciplinary research addressing the ecology of infection