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A Century of Shope Papillomavirus in Museum Rabbit Specimens.

Escudero Duch C, Williams RA, Timm RM, Perez-Tris J, Benitez L - PLoS ONE (2015)

Bottom Line: Prevalence of symptomatic individuals was significantly higher in Sylvilagus (1.8%) than Lepus.Using multiple methodologies, rolling circle amplification and, multiple isothermal displacement amplification in addition to PCR, greatly improved detection rates.Our results do not clarify whether strains are host species specific, though they are consistent with SfPV specificity to genus Sylvilagus.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology III, Faculty of Biological Sciences, Universidad Complutense de Madrid, Madrid, Spain.

ABSTRACT
Sylvilagus floridanus Papillomavirus (SfPV) causes growth of large horn-like tumors on rabbits. SfPV was described in cottontail rabbits (probably Sylvilagus floridanus) from Kansas and Iowa by Richard Shope in 1933, and detected in S. audubonii in 2011. It is known almost exclusively from the US Midwest. We explored the University of Kansas Natural History Museum for historical museum specimens infected with SfPV, using molecular techniques, to assess if additional wild species host SfPV, and whether SfPV occurs throughout the host range, or just in the Midwest. Secondary aims were to detect distinct strains, and evidence for strain spatio-temporal specificity. We found 20 of 1395 rabbits in the KU collection SfPV symptomatic. Three of 17 lagomorph species (S. nuttallii, and the two known hosts) were symptomatic, while Brachylagus, Lepus and eight additional Sylvilagus species were not. 13 symptomatic individuals were positive by molecular testing, including the first S. nuttallii detection. Prevalence of symptomatic individuals was significantly higher in Sylvilagus (1.8%) than Lepus. Half of these specimens came from Kansas, though new molecular detections were obtained from Jalisco-Mexico's first-and Nebraska, Nevada, New Mexico, and Texas, USA. We document the oldest lab-confirmed case (Kansas, 1915), pre-dating Shope's first case. SfPV amplification was possible from 63.2% of symptomatic museum specimens. Using multiple methodologies, rolling circle amplification and, multiple isothermal displacement amplification in addition to PCR, greatly improved detection rates. Short sequences were obtained from six individuals for two genes. L1 gene sequences were identical to all previously detected sequences; E7 gene sequences, were more variable, yielding five distinct SfPV1 strains that differing by less than 2% from strains circulating in the Midwest and Mexico, between 1915 and 2005. Our results do not clarify whether strains are host species specific, though they are consistent with SfPV specificity to genus Sylvilagus.

No MeSH data available.


Related in: MedlinePlus

Distribution of the SfPV1 cases and three known Sylvilagus hosts.Host distributions are depicted with different shading [16]. Similarly SfPV case locations are color coded for host species, etc. See legend for details. Outer circles to points indicate SfPV positive samples, their absence indicates symptomatic individuals. We omit the locality of one symptomatic S. audubonii and CRPV Hershey “Kansas” (GenBank Acc. No: JF303889), for which locality information was missing or vague.
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pone.0132172.g004: Distribution of the SfPV1 cases and three known Sylvilagus hosts.Host distributions are depicted with different shading [16]. Similarly SfPV case locations are color coded for host species, etc. See legend for details. Outer circles to points indicate SfPV positive samples, their absence indicates symptomatic individuals. We omit the locality of one symptomatic S. audubonii and CRPV Hershey “Kansas” (GenBank Acc. No: JF303889), for which locality information was missing or vague.

Mentions: The natural hosts for SfPV infection are cottontail rabbits of genus Sylvilagus although precise knowledge of the taxonomic range of SfPV host species is not well known. We confirm the presence of SfPV1 in three partially sympatric species of Sylvilagus, two of which (S. floridanus and S. audubonii) had previously been described as SfPV1 hosts (Fig 4). SfPV1 infection in the mountain cottontail rabbit (S. nuttallii) has not been recognized previously. All three species of Sylvilagus are closely related [41]. Previous laboratory infection studies [9] have shown that SfPV can infect other leporids, so it is unsurprising that an additional Sylvilagus species should be susceptible in the wild. Our results support the hypothesis that SfPV1 is not strictly associated with Sylvilagus floridanus, and provide evidence for natural infection of two additional Sylvilagus species. Prevalence rates did not differ significantly in the three positive species. However, we advise caution in interpreting these data, as representation of most negative specimens was low for meaningful comparison, and sampling, at least of S. floridanus, was biased. All recent infected S. floridanus (N = 4) were deliberately collected because they were symptomatic, and we assume that interesting “warty rabbits” were more likely to be retained for the KU collection than an ordinary rabbit. On the other hand, many specimens with inconspicuous growths would not have been retained for the collection. However, while general prevalence data may be biased, there is no reason to have sampled lesion-positive individuals more frequently in one species than in others. This suggests that prevalence rates of symptomatic individuals in Sylvilagus and S. floridanus are indeed significantly greater than in Lepus. All specimens were inspected visually and palpated. It is possible, though examination of specimens was very thorough, that small lesions were missed when obscured by fur. A single (missed) finding among species with less than 50 individuals might change the conclusions, though obviously the probability of false negatives is, a priori, no lower in species with a large sample size than a smaller one. A systematic screening of asymptomatic specimens, or better from freshly sampled wild individuals, might obtain a better estimate of SfPV prevalence, though it is beyond the scope of this study.


A Century of Shope Papillomavirus in Museum Rabbit Specimens.

Escudero Duch C, Williams RA, Timm RM, Perez-Tris J, Benitez L - PLoS ONE (2015)

Distribution of the SfPV1 cases and three known Sylvilagus hosts.Host distributions are depicted with different shading [16]. Similarly SfPV case locations are color coded for host species, etc. See legend for details. Outer circles to points indicate SfPV positive samples, their absence indicates symptomatic individuals. We omit the locality of one symptomatic S. audubonii and CRPV Hershey “Kansas” (GenBank Acc. No: JF303889), for which locality information was missing or vague.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493010&req=5

pone.0132172.g004: Distribution of the SfPV1 cases and three known Sylvilagus hosts.Host distributions are depicted with different shading [16]. Similarly SfPV case locations are color coded for host species, etc. See legend for details. Outer circles to points indicate SfPV positive samples, their absence indicates symptomatic individuals. We omit the locality of one symptomatic S. audubonii and CRPV Hershey “Kansas” (GenBank Acc. No: JF303889), for which locality information was missing or vague.
Mentions: The natural hosts for SfPV infection are cottontail rabbits of genus Sylvilagus although precise knowledge of the taxonomic range of SfPV host species is not well known. We confirm the presence of SfPV1 in three partially sympatric species of Sylvilagus, two of which (S. floridanus and S. audubonii) had previously been described as SfPV1 hosts (Fig 4). SfPV1 infection in the mountain cottontail rabbit (S. nuttallii) has not been recognized previously. All three species of Sylvilagus are closely related [41]. Previous laboratory infection studies [9] have shown that SfPV can infect other leporids, so it is unsurprising that an additional Sylvilagus species should be susceptible in the wild. Our results support the hypothesis that SfPV1 is not strictly associated with Sylvilagus floridanus, and provide evidence for natural infection of two additional Sylvilagus species. Prevalence rates did not differ significantly in the three positive species. However, we advise caution in interpreting these data, as representation of most negative specimens was low for meaningful comparison, and sampling, at least of S. floridanus, was biased. All recent infected S. floridanus (N = 4) were deliberately collected because they were symptomatic, and we assume that interesting “warty rabbits” were more likely to be retained for the KU collection than an ordinary rabbit. On the other hand, many specimens with inconspicuous growths would not have been retained for the collection. However, while general prevalence data may be biased, there is no reason to have sampled lesion-positive individuals more frequently in one species than in others. This suggests that prevalence rates of symptomatic individuals in Sylvilagus and S. floridanus are indeed significantly greater than in Lepus. All specimens were inspected visually and palpated. It is possible, though examination of specimens was very thorough, that small lesions were missed when obscured by fur. A single (missed) finding among species with less than 50 individuals might change the conclusions, though obviously the probability of false negatives is, a priori, no lower in species with a large sample size than a smaller one. A systematic screening of asymptomatic specimens, or better from freshly sampled wild individuals, might obtain a better estimate of SfPV prevalence, though it is beyond the scope of this study.

Bottom Line: Prevalence of symptomatic individuals was significantly higher in Sylvilagus (1.8%) than Lepus.Using multiple methodologies, rolling circle amplification and, multiple isothermal displacement amplification in addition to PCR, greatly improved detection rates.Our results do not clarify whether strains are host species specific, though they are consistent with SfPV specificity to genus Sylvilagus.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology III, Faculty of Biological Sciences, Universidad Complutense de Madrid, Madrid, Spain.

ABSTRACT
Sylvilagus floridanus Papillomavirus (SfPV) causes growth of large horn-like tumors on rabbits. SfPV was described in cottontail rabbits (probably Sylvilagus floridanus) from Kansas and Iowa by Richard Shope in 1933, and detected in S. audubonii in 2011. It is known almost exclusively from the US Midwest. We explored the University of Kansas Natural History Museum for historical museum specimens infected with SfPV, using molecular techniques, to assess if additional wild species host SfPV, and whether SfPV occurs throughout the host range, or just in the Midwest. Secondary aims were to detect distinct strains, and evidence for strain spatio-temporal specificity. We found 20 of 1395 rabbits in the KU collection SfPV symptomatic. Three of 17 lagomorph species (S. nuttallii, and the two known hosts) were symptomatic, while Brachylagus, Lepus and eight additional Sylvilagus species were not. 13 symptomatic individuals were positive by molecular testing, including the first S. nuttallii detection. Prevalence of symptomatic individuals was significantly higher in Sylvilagus (1.8%) than Lepus. Half of these specimens came from Kansas, though new molecular detections were obtained from Jalisco-Mexico's first-and Nebraska, Nevada, New Mexico, and Texas, USA. We document the oldest lab-confirmed case (Kansas, 1915), pre-dating Shope's first case. SfPV amplification was possible from 63.2% of symptomatic museum specimens. Using multiple methodologies, rolling circle amplification and, multiple isothermal displacement amplification in addition to PCR, greatly improved detection rates. Short sequences were obtained from six individuals for two genes. L1 gene sequences were identical to all previously detected sequences; E7 gene sequences, were more variable, yielding five distinct SfPV1 strains that differing by less than 2% from strains circulating in the Midwest and Mexico, between 1915 and 2005. Our results do not clarify whether strains are host species specific, though they are consistent with SfPV specificity to genus Sylvilagus.

No MeSH data available.


Related in: MedlinePlus