Disease Risk Assessments Involving Companion Animals: an Overview for 15 Selected Pathogens Taking a European Perspective

Prioritization of companion animal transmissible diseases was performed by the Companion Animals multisectoriaL interprofessionaL Interdisciplinary Strategic Think tank On zoonoses (CALLISTO) project. The project considered diseases occurring in domesticated species commonly kept as pets, such as dogs and cats, but also included diseases occurring in captive wild animals and production animal species. The prioritization process led to the selection of 15 diseases of prime public health relevance, agricultural economic importance, or both. An analysis was made of the current knowledge on the risk of occurrence and transmission of these diseases among companion animals, and from companion animals to man (zoonoses) or to livestock. The literature was scanned for risk assessments for these diseases. Studies were classified as import risk assessments (IRAs) or risk factor analyses (RFAs) in endemic areas. For those pathogens that are absent from Europe, only IRAs were considered; for pathogens present throughout Europe, only RFAs were considered. IRAs were identified for seven of the eight diseases totally or partially absent from Europe. IRAs for classical rabies and alveolar echinococcosis found an increased risk for introduction of the pathogen into officially disease-free areas as a consequence of abandoning national rules and adopting the harmonized EU rules for pet travel. IRAs for leishmaniosis focused on risk associated with the presence of persistently infected dogs in new geographical areas, taking into consideration the risk of disease establishment should a competent vector arise. IRAs for Crimean–Congo haemorrhagic fever and West Nile fever indicated that the likelihood of introduction via companion animals was low. IRAs for bluetongue paid no attention to the risk of introduction via companion animals, which was also the case for IRAs for foot-and-mouth disease, the only disease considered to be absent from Europe. RFAs dealing with the risk factors for companion animals to become infected were identified for eight of the 14 diseases found in Europe or parts of it. RFAs for leptospirosis were most numerous (four studies). The host related risk factor ‘age’ was identified as significant for dogs in at least two RFAs for cystic echinococcosis and giardiasis. Among husbandry and healthcare related factors, ‘eating (uncooked) offal’, ‘being free roaming’ and ‘poor deworming practice’ were associated with risk for dogs in at least two RFAs for cystic e