The role of wild canids and felids in spreading parasites to dogs and cats in Europe Part I: Protozoa and tick-borne agents

Over the last few decades, the world has witnessed radical changes in climate, landscape, and ecosystems.These events, together with other factors such as increasing illegal wildlife trade and changing humanbehaviour towards wildlife, are resulting into thinning boundaries between wild canids and felids andtheir domestic counterparts. As a consequence, the epidemiology of diseases caused by a number ofinfectious agents is undergoing profound readjustements, as pathogens adapt to new hosts and environ-ments. Therefore, there is a risk for diseases of wildlife to spread to domestic carnivores and vice versa,and for zoonotic agents to emerge or re-emerge in human populations. Hence, the identification of thehazards arising from the co-habitation of these species is critical in order to plan and develop adequatecontrol strategies against these pathogens. In the first of this two-part article, we review the role thatwild canids and felids may play in the transmission of protozoa and arthropod-borne agents to dogs andcats in Europe, and provide an account of how current and future progress in our understanding of theecology and epidemiology of parasites, as well as of host-parasite interactions, can assist efforts aimedat controlling parasite transmission.