Vector-borne diseases are caused by parasites, bacteria or viruses transmitted by
the bite of hematophagous arthropods (mainly ticks and mosquitoes). The past few years
have seen the emergence of new diseases, or re-emergence of existing ones, usually
with changes in their epidemiology (i.e. geographical distribution, prevalence, and
pathogenicity). The frequency of some vector-borne diseases of pets is increasing
in Europe, i.e. canine babesiosis, granulocytic anaplasmosis, canine monocytic ehrlichiosis,
thrombocytic anaplasmosis, and leishmaniosis. Except for the last, these diseases
are transmitted by ticks. Both the distribution and abundance of the three main tick
species, Rhipicephalus sanguineus, Dermacentor reticulatus and Ixodes ricinus are
changing. The conditions for such changes involve primarily human factors, such as
travel with pets, changes in human habitats, social and leisure activities, but climate
changes also have a direct impact on arthropod vectors (abundance, geographical distribution,
and vectorial capacity). Besides the most known diseases, attention should be kept
on tick-borne encephalitis, which seems to be increasing in western Europe, as well
as flea-borne diseases like the flea-transmitted rickettsiosis. Here, after consideration
of the main reasons for changes in tick vector ecology, an overview of each "emerging"
vector-borne diseases of pets is presented.