Genetic identification of novel poxviruses of cetaceans and pinnipeds

Abstract

Novel poxviruses were identified in skin lesions of several species of cetaceans and pinnipeds using polymerase chain reaction targeting DNA polymerase and DNA topoisomerase I genes of members of the subfamily Chordopoxvirinae. With the exception of parapoxviruses, no molecular data of marine mammal poxviruses were available to infer genetic and evolutionary relatedness to terrestrial vertebrate poxviruses. Viruses were assigned to a cetacean poxvirus 1 (CPV-1) group based on nucleotide and amino acid identities of gene fragments amplified from skin lesions of Asian bottlenose (Tursiops aduncus), Atlantic bottlenose (Tursiops truncatus), rough-toothed (Steno bredanensis), and striped (Stenella coeruleoalba) dolphins. A different poxvirus was detected in skin lesions of a bowhead whale (Balaena mysticetus) and provisionally assigned to a CPV-2 group. These viruses showed highest identity to terrestrial poxviruses of the genera Orthopoxvirus and Suipoxvirus. A novel species-specific poxvirus was also identified in skin lesions of Steller sea lions (Eumetopias jubatus). None of these poxviruses were found to have amplifiable hemagglutinin gene sequences. Novel parapoxviruses were also identified in skin lesions of Steller sea lions and spotted seals (Phoca largha). A significant degree of divergence was observed in sequences of Steller sea lion parapoxviruses, while those of spotted seals and harbor seals (Phoca vitulina) were highly conserved.

Orthopoxvirus neutralising antibodies in small cetaceans from the Southeast Pacific

“…To date, the only poxviruses microscopically encountered in these mammals are those causing the endemic and distinctive tattoo skin disease and it is highly likely that infection by these viruses elicited the neutralising antibodies detected in this study. Furthermore, we suppose that the poxviruses infecting Peruvian small cetaceans are related to those recently detected by PCR in tattoo-like lesions in S. bredanensis and S. coeruleoalba from the North Atlantic (Bracht et al, 2006). Although these viruses probably belong to a new genus of Chordopoxvirinae, they share a common most immediate ancestor with terrestrial poxviruses (Bracht et al, 2006), which may explain the observed crossneutralization with cowpox virus.…”

“…Other cetacean poxviruses were recently detected in both captive cetaceans, such as Indo-Pacific bottlenose dolphins (Tursiops aduncus), and in free-ranging rough-toothed dolphins (Steno bredanensis), striped dolphins (Stenella coeruleoalba) and bottlenose dolphins (T. truncatus) from Florida. A polymerase chain reaction assay was used, targeting the DNA polymerase and DNA topoisomerase genes of members of the subfamily Chordopoxvirinae (family Poxviridae) (Bracht et al, 2006). These cetacean poxviruses belong to a new genus of Chordopoxvirinae, but have a common, most immediate ancestor with terrestrial poxviruses of the genus Orthopoxvirus (Bracht et al, 2006).…”

“…A polymerase chain reaction assay was used, targeting the DNA polymerase and DNA topoisomerase genes of members of the subfamily Chordopoxvirinae (family Poxviridae) (Bracht et al, 2006). These cetacean poxviruses belong to a new genus of Chordopoxvirinae, but have a common, most immediate ancestor with terrestrial poxviruses of the genus Orthopoxvirus (Bracht et al, 2006). The genus Orthopoxvirus includes, among others, the smallpox virus (now eradicated in humans), vaccinia virus (the smallpox vaccine of unknown origin), and cowpox virus, endemic in European wild rodents and accidentally infecting humans, cats and cattle (Hazel et al, 2000;Esposito et al, 2004).…”

Cutaneous Lesions in Cetaceans: An Indicator of Ecosystem Status?

“…Poxviridae represent the largest family of viruses known to cause diseases in marine and terrestrial mammals [50]. Among cetaceans, the odontocetes seem to be more affected than the mysticetes [49].…”

“…Species of cetaceans reported to be affected by pox viruses, include Atlantic bottlenose dolphins [7,50], bottlenose dolphins from Australia [49], Atlantic whitesided dolphins [7,50], common dolphin (Delphinus delphis), dusky dolphins, white-beaked dolphins (Lagenorhynchus albirostris) [29,50], striped dolphins (Stenella coeruleoalba) [29,50], Hector's dolphins (Cephalorhynchus hectori) [7,29,50], long finned pilot whales (Globocephala melaena) [29,50], as well as a few spp. of porpoises [50]. Dolphin pox has been associated with a variety of lesions, referred to as 'targets', wateredsilk', 'ring', 'pinhole', 'circle' and 'tattoo'-like [7].…”