Part II. Tracing viral disease dissemination in aquaculture: an interdiciplinary approach between molecular virology and dispersal modelling

Viral diseases are a large problem in Norwegian salmon farming imposing economic as well as welfare-related challenges to the industry. In order to control the spread of viral diseases, knowledge on the transmission pathways of the disease agents and key factors affecting the interaction between the disease agent and the host, are vital. Molecular virological methods have proven useful for sensitive detection as well as genomic characterisation in studies on molecular epidemiology of important viral disea ses, making use of phylogenitic analyses and identification of mutations important for virulence. Concomitantly, stochastic modelling of infectious diseases, and the spread of disease in aquaculture systems, is a developing field. The contribution from su ch models is that they may predict the space-time dynamics of disease dispersal. When disease dispersal is reasonably predicted, models can also be valuable as tools to simulate scenarios of importance to disease control or disease surveillance. However, model precision is critically dependent on knowledge of the biological and environmental factors that govern the development of host-pathogen interactions, and thus disease development. The present project proposal suggests an interdisciplinary approach o f molecular virology and stochastic disease modelling to disentangle major transmission pathways of infectious salmon anaemia virus, and molecular characteristics of virus traits that may affect the probability of disease outbreaks.