Phylogenetic analysis of canine distemper virus in South African wildlife

Abstract

Canine distemper virus (CDV) causes a severe contagious disease in a broad range of hosts. This is the first study to genetically characterise CDV strains from four different wildlife species in South Africa. The phylogenetic diversity of CDV is examined, using the haemagglutinin gene. The South African wildlife CDV isolates showed a high degree of similarity to CDV in South African domestic dogs. Phylogenetic analyses confirmed the presence of 12 geographical lineages with CDV strains from South African wildlife falling within the Southern African lineage. The study reveals two possible co-circulating sub-genotypes corresponding to the northern and southern regions of South Africa respectively. CDV strains from the non-canid species were distinct, but similar to CDV isolates from domestic dog and wild canids. Residues at amino acid sites of the SLAM binding region support the notion that CDV strains encoding 519I / 549H are better adapted to non-canid species than canid species. The amino acids present at site 530 are conserved regardless of host species. Strains from South African wild carnivores showed no difference between host species with all strains presenting 530N. All non-canid strains in this study presented the combination 519I/549H. No evidence of host adaptation or lineage grouping was observed for the Nectin-4 binding region. Further studies should include CDV strains isolated from various hosts from a wider geographical range in South Africa.

Sylvatic Canine Morbillivirus in Captive Panthera Highlights Viral Promiscuity and the Need for Better Prevention Strategies

“…Along with well-conserved H-genes shared with local wildlife, this outbreak further supports the argument that no significant species-adaptation is needed for CDV species-jump and spread. In addition to other natural spillovers [ 3 , 10 , 17 , 33 , 48 ], experimental reports have shown that the same holds true even for cells expressing human nectin-4 [ 49 ]. Bieringer et al 2013 also reported that a single functional adaptation was required (D540G) for CDV adaptation to human SLAM.…”

“…All these sites have been subject of speculation regarding the CDV’s ability to jump species, particularly to non-canids [ 27 , 28 , 29 , 30 ]. However, an ever growing number of authors see no significant difference among residues in multi-host strains or virus-targeted host receptors [ 19 , 26 , 31 , 32 , 33 ], but rather, pleiotropic and temporal, sometimes concurrent, geographical clades seem to be the cause for outbreaks and CDV evolution [ 23 , 33 , 34 , 35 ]. Nonetheless, though H-gene has been largely used for phylogenetic studies, full genome phylogenetic trees are increasingly preferred and have helped identify other genetic sites where recombination may play a significant role in CDV evolution [ 24 , 36 ].…”

Canine and Phocine Distemper Viruses: Global Spread and Genetic Basis of Jumping Species Barriers

“…This outbreak also infected other carnivore species, resulting in the first reported case of CDV mortality in an endangered brown hyena ( Hyaena brunnea ). Four months later, the devastating effect of CDV was also observed in African wild dog populations of Kruger National Park and Tswalu Kalahari Reserve, South Africa, with the total eradication of two packs [53]. This raises questions with regard to the virulence and pathogenicity of circulating virus strains.…”

A novel and highly divergent Canine Distemper Virus lineage causing distemper in ferrets in Australia

“…Severe systemic infection can occur in immunologically naïve animals (3,8), with long periods of viral shedding, with infection in domestic dogs previously reported to last as long as 90 days (9). CDV is highly contagious in many species of animals (6), and resultant mortality rates vary in animal populations and across the species affected (8). For example, mortality has ranged from 23% in the Chinese giant panda (Ailuropoda melanoleuca) (10) to 100% in ferrets (Mustela putorius furo) (11).…”

“…There is a global vaccination strategy in place for the management and control of CDV with most countries, including Australia, generally utilizing a modified live attenuated vaccine based on the Onderstepoort strain. While this strategy is important in controlling this virus in dogs (8,16,20) there are a number of records where there is evidence of vaccine-induced CDV infections in both domesticated dogs and in wildlife through reversion of attenuation in the vaccine strain (6,21). For example, CDV cases in wildlife due to the vaccine strain infection have been reported in South Africa and the UK (6,22,23).…”