Epidemiology, Pathology, and Genetic Analysis of a Canine Distemper Epidemic in Namibia

Abstract

ABSTRACT:Severe population declines have resulted from the spillover of canine distemper virus (CDV) into susceptible wildlife, with both domestic and wild canids being involved in the maintenance and transmission of the virus. This study (March 2001 to October 2003 collated case data, serologic, pathologic, and molecular data to describe the spillover of CDV from domestic dogs (Canis familiaris) to black-backed jackals (Canis mesomelas) during an epidemic on the Namibian coast. Antibody prevalence in jackals peaked at 74.1%, and the clinical signs and histopathologic observations closely resembled those observed in domestic dog cases. Viral RNA was isolated from the brain of a domestic dog from the outbreak area. Sequence data from the phosphoprotein (P) gene and the hemagglutinin (H) genes were used for phylogenetic analyses. The P gene sequence from the domestic dog shared 98% identity with the sequence data available for other CDV isolates of African carnivores. For the H gene, the two sequences available from the outbreak that decimated the lion population in Tanzania in 1994 were the closest match with the Namibian sample, being 94% identical across 1,122 base pairs (bp). Phylogenetic analyses based on this region clustered the Namibian sample with the CDV that is within the morbilliviruses. This is the first description of an epidemic involving black-backed jackals in Namibia, demonstrating that this species has the capacity for rapid and large-scale dissemination of CDV. This work highlights the threat posed to endangered wildlife in Namibia by the spillover of CDV from domestic dog populations. Very few sequence data are currently available for CDV isolates from African carnivores, and this work provides the first sequence data from a Namibian CDV isolate.

Cross-species transmission of canine distemper virus—an update

“…Affected members of the genus Canis include Australian dingos ( Canis dingo ) [27], coyotes ( Canis latrans ) [28], [29], black-backed jackals ( Canis mesomelas ) [30], golden jackals ( Canis aureus ) [31], Canadian wolves ( Canis lupus ) [32], American gray wolves ( Canis lupus ) [33], Mexican wolves ( Canis lupus baileyi ) [34], Iberian wolves ( Canis lupus ) [35], and Apennine wolves ( Canis lupus ) [36]. Phylogenetic analyses suggest a CDV spillover from domestic dogs to free-ranging jackals and wolves [30], [35]. Referring to this, sequencing of CDV from Apennine wolves in Italy identified a strain belonging to the Arctic lineage, known to circulate in European dog populations [36].…”

Epidemiological features and the neuropathological manifestations of canine distemper virus-induced infections in Brazil: a review

“…Therefore, the large amount of mongrels that are easily encountered in several rural and semi-urban cities of Brazil would serve not only as reservoirs and distributors of CDV, but for other infectious disease agents, thereby excluding the necessity of having a wildlife species serving as an intermediate host for CDV in Brazil, as is described in North America (KAPIL et al, 2008) and Europe (MEYERS et al, 1997;PHILIPPA et al, 2008). Free roaming domestic dogs were also incriminated as being responsible for the spillover effect of CDV to black-backed jackals (Canis mesomelas) in Namibia, Africa (GOWTAGE-SEQUEIRA et al, 2009), to the Serengeti wildlife epidemic in Tanzania (CLEAVELAND et al, 2000), and possibly to the Iberian lynxes, whose population is estimated to be approximately 200 individuals (MELI et al, 2010).…”

Simultaneous Detection of Canine Respiratory Disease Associated Viruses by a Multiplex Reverse Transcription-Polymerase Chain Reaction Assay

“…Serological surveys carried out in South Korea, Italy, U.K., Ireland, U.S.A. and Japan [2,6,7,22,24], have identified CRCoV as a worldwide pathogen found in the respiratory tract of dogs suffering from mild or severe respiratory disease. CDV is one of the most serious diseases in domestic dogs worldwide [11,13,14,16]. It is highly contagious, affects dogs of all ages and is associated with high morbidity and mortality [10,21].…”