Species: Rhesus monkey Strain/breeder: n.a. Sex: Female Age: 1 year Study type: n.a. Treatment: No treatment Animal status: Intercurrent death Clinical findings: Multiple small moist skin lesions on pinna, nose, thorax, and forearm Organ(s): Spleen Macroscopic finding(s): Necrotizing cheilitis, gingivitis, and osteitis Staining: H&E

Fig. 1 (73k)

Abstract

R. PLESKER¹, B. DURCHFELD-MEYER², and M. HEINRICHS²

¹Paul-Ehrlich-Institut, Paul-Ehrlich-Str. 51-59, 63225 Langen, Germany
²Aventis Pharma Deutschland GmbH, Hattersheim, Germany

Key words: herpes virus, cytomegalovirus, herpes B virus

A non-experimental one-year-old female rhesus macaque showed clinically multiple small moist skin lesions on pinna, nose, thorax, and one forearm. At necropsy, a necrotising cheilitis, gingivitis, and osteitis were diagnosed. Histopathologically, in spleen, liver, heart, and lymphnodes, large basophilic intranuclear inclusion bodies were found in varying numbers. Ultrastructurally, herpes viruses were demonstrated. Dense bodies in the cytoplasm of affected cells were interpreted as indicative of CMV-like herpes viruses. Immunocytochemially, cytomegalovirus infection was confirmed.

For differential diagnosis, a herpes B-virus infection must be taken into consideration, especially if cheilitis and gingivitis are seen in a macaque. In these species, the incidence of infection can reach 80-90%. A serologic test (ELISA) can confirm an infection, however, false seronegative individuals do occur. A more sensitive PCR can only be positive, if virus DNA is present in the specimen. Since the virus can stay latent in sensory ganglia for a life-time, infected monkeys always pose a potential zoonotic risk for human beings. This is particularly true for individuals with herpes virus-induced vesicles on the lips and those having viraemia.