Genetic Characterization of Feline Leukemia Virus from Florida Panthers

National Cancer Institute, Frederick, Maryland, USA.
Emerging infectious diseases (Impact Factor: 6.75). 03/2008; 14(2):252-9. DOI: 10.3201/eid1402.070981
Source: PubMed


From 2002 through 2005, an outbreak of feline leukemia virus (FeLV) occurred in Florida panthers (Puma concolor coryi). Clinical signs included lymphadenopathy, anemia, septicemia, and weight loss; 5 panthers died. Not associated with FeLV outcome were the genetic heritage of the panthers (pure Florida vs. Texas/Florida crosses) and co-infection with feline immunodeficiency virus. Genetic analysis of panther FeLV, designated FeLV-Pco, determined that the outbreak likely came from 1 cross-species transmission from a domestic cat. The FeLV-Pco virus was closely related to the domestic cat exogenous FeLV-A subgroup in lacking recombinant segments derived from endogenous FeLV. FeLV-Pco sequences were most similar to the well-characterized FeLV-945 strain, which is highly virulent and strongly pathogenic in domestic cats because of unique long terminal repeat and envelope sequences. These unique features may also account for the severity of the outbreak after cross-species transmission to the panther.

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    • "For instance, it has been shown that FeLV-B arose through recombination in the env region between FeLV-A and endogenous FeLV sequences (enFeLV) present in the feline genome [9], [26], and FeLV-C apparently also arose through deletion and mutation of the FeLV-A env gene [2], [27]. Since the initial discovery of FeLV in domestic cats in 1964 [28]–[29], the virus has also been isolated from wild cats such as the Florida panther [30] and the Iberian lynx [31]. Preventing FeLV infection in both domestic and wild cats is of considerable interest. "
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    PLoS ONE 04/2013; 8(4):e61009. DOI:10.1371/journal.pone.0061009 · 3.23 Impact Factor
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    • "Consumption of free-roaming cats by cougar or panther (Felis concolor) poses a risk of FeLV transmission , and suspected cases of domestic cat-transmitted FeLV in wild felids have been reported in California and Florida (Jessup et al., 1993; Cunningham et al., 2008). Genetic analysis of the FeLV virus associated with mortality in 5 Florida panthers indicated that the virus envelope sequence was nearly identical indicating the source or the infection was likely from a single domestic cat (Brown et al., 2008). "
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    Zoonoses and Public Health 07/2012; 60(3). DOI:10.1111/j.1863-2378.2012.01522.x · 2.37 Impact Factor
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    • "Wild felids isolated by habitat fragmentation exhibit “home-range pile-up” [10] and the potential for increased contact rates with conspecifics. Contact between domestic cats and non-domestic felids can lead to cross-species FIV transmission events, such as has apparently occurred with feline leukemia virus transmission between domestic cats and pumas in Florida [54]. Additionally, recent spatial analyses have suggested that landscape features, and in particular roads, could impact FIV infections in pumas [55]. "
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