The article analyses the organisational and regulatory processes related to public health protection activities by exploring the relationship between production and implementation of legislation and scientific instances in a specific case study, i.e. the West Nile Virus integrated surveillance in Northern Italy, according to One Health’s perspectives. Because of its scientific root, in this field rules consist of elements of both a technical and a political nature. According to the results of the focus-group research in three Italian regions, the authors suggest the need of more investigation on the organizational and regulatory integration processes. As the One Health-oriented perspective states, trans-disciplinary and trans-sectorial collaboration, including integration between different actors, knowledge, norms and policy objectives, is nec-essary for the collective protection. Empirical evidence shows how such integration is achieved through the construction of "communities of practice", which share many characteristics of the semi-autonomous social fields identified by Moore.
Keywords: Rules - One Health - Semi-autonomous social field - Organizational integration