title: The pox in the North American backyard: Volepox virus pathogenesis in California mice (Peromyscus californicus).
abstract: Volepox virus (VPXV) was first isolated in 1985 from a hind foot scab of an otherwise healthy California vole (Microtus californicus). Subsequent surveys in San Mateo County, CA, revealed serological evidence suggesting that VPXV is endemic to this area, and a second viral isolate from a Pinyon mouse (Peromyscus truei) was collected in 1988. Since then, few studies have been conducted regarding the ecology, pathology, and pathogenicity of VPXV, and its prevalence and role as a potential zoonotic agent remain unknown. To increase our understanding of VPXV disease progression, we challenged 24 California mice (Peromyscus californicus) intranasally with 1.6 × 10(3) PFU of purified VPXV. By day five post infection (pi) we observed decreased activity level, conjunctivitis, ruffled hair, skin lesions, facial edema, and crusty noses. A mortality rate of 54% was noted by day eight pi. In addition, internal organ necrosis and hemorrhages were observed during necropsy of deceased or euthanized animals. Viral loads in tissues (brain, gonad, kidney, liver, lung, spleen, submandibular lymph node, and adrenal gland), bodily secretions (saliva, and tears), and excretions (urine, and/or feces) were evaluated and compared using real time-PCR and tissue culture. Viral loads measured as high as 2 × 10(9) PFU/mL in some organs. Our results suggest that VPXV can cause extreme morbidity and mortality within rodent populations sympatric with the known VPXV reservoirs.
authors.affiliation: Poxvirus and Rabies Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America. hfa5@cdc.gov
authors.forename: Nadia F
authors.initials: NF
authors.lastname: Gallardo-Romero
authors.forename: Clifton P
authors.initials: CP
authors.lastname: Drew
authors.forename: Sonja L
authors.initials: SL
authors.lastname: Weiss
authors.forename: Maureen G
authors.initials: MG
authors.lastname: Metcalfe
authors.forename: Yoshinori J
authors.initials: YJ
authors.lastname: Nakazawa
authors.forename: Scott K
authors.initials: SK
authors.lastname: Smith
authors.forename: Ginny L
authors.initials: GL
authors.lastname: Emerson
authors.forename: Christina L
authors.initials: CL
authors.lastname: Hutson
authors.forename: Johanna S
authors.initials: JS
authors.lastname: Salzer
authors.forename: Jeanine H
authors.initials: JH
authors.lastname: Bartlett
authors.forename: Victoria A
authors.initials: VA
authors.lastname: Olson
authors.forename: Cody J
authors.initials: CJ
authors.lastname: Clemmons
authors.forename: Whitni B
authors.initials: WB
authors.lastname: Davidson
authors.forename: Sherif R
authors.initials: SR
authors.lastname: Zaki
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Karem
authors.forename: Inger K
authors.initials: IK
authors.lastname: Damon
authors.forename: Darin S
authors.initials: DS
authors.lastname: Carroll
mesh_terms: D000818:Animals; D004279:DNA, Viral / Q000032:analysis / Q000235:genetics; D005260:Female; D006403:Hematologic Tests; D056724:Immunity, Humoral; D008297:Male; D009656:North America; D018155:Orthopoxvirus / Q000472:pathogenicity*; D010542:Peromyscus / Q000821:virology; D011213:Poxviridae Infections / Q000097:blood / Q000453:epidemiology / Q000276:immunology / Q000662:veterinary
chemical_list: D004279:DNA, Viral