Volepox Virus

The first instance of the volepox virus (VPXV) was discovered in a hind foot scab of a healthy California vole in 1985. Serological data from later investigations in San Mateo County, California, suggested that VPXV is indigenous to this region, and a second virus strain from a Pinyon mouse was discovered in 1988. Since then, not many studies have been done on the ecology, pathology, and pathogenicity of VPXV, and it is still unclear how common it is and how it can act as a possible zoonotic agent.

Background of Volepox Virus

The Orthopoxvirus family includes the double-stranded DNA virus VPX. On the chorioallantoic membranes of chick embryos, VPX caused pinpoint, nonhemorrhagic pocks. There was a significant amount of cross-hybridization between the DNAs of VPX and other orthopoxviruses, however HindIII cleavage site maps revealed distinct central and terminal regions between VPX (222.8 kbp) and mapped DNAs of other orthopoxviruses.

Symptoms of Volepox

There were 31 infected adult California mice. By day five, majority of the animals had developed a number of clinical symptoms as well as "pox-like" skin lesions. There were numerous epidermal hyperemias with a diameter of 1-3 mm on the tails, as well as papulae and maculae on the eyelids, paws, ears, lips, and oral commissures. Three mice had died of the illness by day six, and three more were put to death in accordance with the clinical scale standards mentioned in the methods section. Seven days later, two more mice had passed away and three more had been put to death. During the necropsy of the dead and euthanized animals, petechiae were seen on the internal organs and skin papulae and maculae developed to erosions. Eighth day saw the deaths of two more animals, bringing the overall mortality rate to 54%.

Reference

1. Gallardo-Romero, Nadia F et al. “The pox in the North American backyard: Volepox virus pathogenesis in California mice (Peromyscus californicus).” PloS one vol. 7,8 (2012): e43881.
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