Fatal Poxvirus Outbreak in a Colony of New World Monkeys

Abstract

Abstract. An epizootic infection was observed in a colony of 80 New World monkeys consisting of various species including a group of marmosets and Saguinus species. During the summer and autumn of 2002, 30 animals died of unknown diseases. Six animals were sent to the German Primate Center for investigation of the cause of death. A complete pathologic and histologic investigation was carried out. The animals exhibited erosive-ulcerative lesions of the oral mucous membranes. Advanced stages of the disease were characterised by hemorrhagic lesions on the skin distributed randomly over the body, but principally on the face, scrotal region, soles, and palms. Electron microscopy revealed virus particles with orthopox-like morphology within intracytoplasmic inclusions in epithelial cells. The DNA samples from various tissues were analyzed by use of a set of orthopox virus-specific, real-time polymerase chain reaction assays. Amplification products were sequenced to define the virus more precisely. Sequencing confirmed the presence of an orthopox virus. Sequence data indicated that all six animals were infected with the same virus. Propagation of the virus on Vero cells resulted in a rapidly progressive cytopathogenic effect. Preliminary phylogenetic analyses of two genes revealed closest homology to cowpox viruses. The origin of this poxvirus outbreak remains unexplained, and the strain and genus of the virus need to be determined in detail.

The Pathology of Experimental Poxvirus Infection in Common Marmosets (Callithrix jacchus): Further Characterization of a New Primate Model for Orthopoxvirus Infections

“…Calpox virus is a new CPXV isolated from a lethal OPV outbreak in New World monkeys (Mätz-Rensing et al, 2006). In natural VARV and MPXV infections, unvaccinated human patients generally develop symptoms and some infected individuals die.…”

“…In 2002 a lethal atypical epizootic OPV infection was reported in a colony of 80 New World monkeys in Lower Saxony, Germany (Mätz-Rensing et al, 2006). Sequencing and molecular characterization identified the virus as a new CPXV named calpox virus, after its host Callithrix jacchus, the common marmoset (Ellerbrok, unpublished data).…”

Limited susceptibility of rhesus macaques to a cowpox virus isolated from a lethal outbreak among New World monkeys

“…The calpox virus belongs to the Cowpox virus species and was isolated from Callithrix jacchus during a natural outbreak of the disease in a private New World monkey husbandry (Mätz-Rensing et al, 2006). High doses of the virus experimentally applied to marmosets reproducibly led to death within 4 to 7 days.…”

“…During a natural cowpox outbreak in a sanctuary for exotic animals in the Netherlands, several animals of different macaque species developed neutralizing serum antibody titers, indicating an exposure to the virus, but only three of them developed mild clinical symptoms. Experience of this outbreak suggests that macaques are susceptible to cowpox virus but that the clinical outcome is less severe than in New World monkeys (Martina et al, 2006;Mätz-Rensing et al, 2006). There is evidence that cynomolgus and rhesus macaques are susceptible to CPXV Brighton Red (CPXV-BR).…”

“…Common marmosets are highly susceptible to the calpox virus and they can be infected experimentally via an intravenous or intranasal (i.n.) route (Mätz-Rensing et al, 2006. The intranasal route of infection resembles the natural infection route of smallpox and is therefore a suitable model for the validation of therapeutics and vaccines.…”