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7. Other diseases not listed by OIE 7.1 Canine distemper virus (CDV) Canine distemper virus (CDV) is a Morbillivirus that affects carnivores; a related virus (phocine distemper virus) affects seals. CDV is not listed by OIE as it does not affect food animals. Canine distemper is a severe multisystemic disease that usually culminates in neurological disturbances and death. CDV occurs worldwide and is probably one of the most important causes of mortality in dogs in unvaccinated populations. It is likely to be widespread in all unvaccinated dog populations in and around the KAZA TFCA. The disease is highly contagious and a wide range of carnivores can be infected. Transmission is by direct contact and via aerosol droplets. The virus is unable to survive for long outside the host but some infected dogs may shed virus for several months. The importance of CDV at the wildlife/domestic animal interface is recognised worldwide because of its ability to infect a wide range of wild carnivores, some of which are highly threatened species like the Ethiopian wolf (Canis simensis) and African wild dog (Lycaon pictus). There is no information on the level of occurrence of CVD in domestic dog populations, but some devastating outbreaks in wildlife have been reported, with the loss of entire packs of African wild dogs and significant numbers of lions in the Serengeti ecosystem (Cleaveland et al. 2007). The effects of CDV in wild populations appears to be variable, as a survey for antibodies to various carnivore viruses revealed that lions in the Kgalagadi TFCA and Okavango Delta in Botswana had antibodies to CDV without disease having been reported (Alexander et al. 2010). The same study reported seroconversion to CDV in African wild dogs in the Okavango Delta with no apparent ill effects. Seroconversion has also been reported in Ethiopian wolf (Laurenson et al. 1998). However, an outbreak of neurological disease in lions in the Kgalagadi TFCA in 2010 was initially suspected to be rabies but samples proved negative for that disease and it now seems certain that it was CDV although confirmatory laboratory diagnosis is lacking. Typical ‘chewing gum fits’ associated with CDV were observed and filmed in lions in the Kgalagadi (M. Hofmeyr, pers. comm. 2010) and high mortality was reported. Cleaveland et al. 2007 also noted the variability in pathogenicity of CDV in lions. CDV has been associated with disease in captive cheetah but a serological survey in free-­‐ranging cheetah on farmland in Namibia where there was contact with domestic dogs found antibodies in several healthy cheetah sampled (Munson et al. 2004). Because of the potential for serious losses among rare species there is no doubt that CDV is an interface disease of concern owing to the presence of unvaccinated dog populations in close proximity to conservation areas. CDV has virtually disappeared in urban dog populations where most of the dogs are vaccinated. Attempting to protect any wild species by vaccination is challenging, and while it may be necessary in the case of rabies, applying vaccination for CDV in wildlife may not be necessary (Prager et al. 2011), particularly if it can be relatively easily controlled in dog populations at the interface by vaccination. 37