Some herpesviruses can cause disease in nonhuman primates, especially the herpes simplex, whose only natural host is the human. Herpes simplex can cause lethal disease in marmosets.4 Symptoms typical of a herpesvirus infection are vesicular and necrotic plaques, erosion and ulceration of oral mucosa and the mucocutaneous border. These alterations are associated with keratitis and conjunctivitis. Additionally, some animals develop meningitis and meningoencephalitis. There have been descriptions in the literature of marmosets with herpes simplex1 or putative cases2,3,5 only from captivity. These animals died within 2–5 days after the appearance of the ulcerations described above.2
In 1995, a very sick C. penicillata from Serra da Tiririca State Park was brought to the Polyclinic of the Veterinary School of UFF. According to the case history, many more sick animals could be found at the same site. A herpesvirus infection was diagnosed through clinical findings, necropsy, histopathological investigations and electron microscopy.
During clinical examination and necropsy, small blisters and ulcers of the tongue, soft palatine and infra-ocular area were found. The retropharyngeal lymph nodes showed hyperplasia. In the gastrointestinal tract, parasitosis could be diagnosed. The lung showed multiple tumors. In the histological examination, we found shallow ulcers with inflammatory reaction and intranuclear inclusion bodies, typical of herpes of the tongue, soft palatine and skin. We also observed follicular hyperplasia in the spleen as well as retropharyngeal lymph node and necrosis of the liver. The lungs showed emphysema, alveolar edema, acute intra-alveolar hemorrhagia, parasites and tumoral masses. Under electron microscopy, the virus could be seen in skin and mucosa. It was located intranuclearly as well as intracytoplasmatically and showed characteristics of herpesvirus, suggesting herpes simplex.
As mentioned above Callithrix spp. are susceptible to herpes simplex.1-5 There is, however, no evidence for such an infection in wild marmosets, specifically C. penicillata. The most probable means of transmission of herpesvirus is direct contact with the saliva of the infected subjects.1 Nevertheless, such a virus can also be transmitted by, for example, domestic utensils a short time after contamination.1 The marmosets in the park have substantial contact with the man who feeds them. A transmission of herpes simplex is therefore likely to have occurred through this vector.
Many thanks to Instituto Estadual de Florestas (IEF) and Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (IBAMA) for their cooperation.
1. Da Cruz JB. 1985. Herpes simplex em Callithrix penicillata (Geoffroy, 1812). Callitrichidae - Primates. Niterói RJ. 47p. Tese (Concurso para Professor Titular). Disciplina de Anatomia Patológica da Universidade Federal Fluminense.
2. Maia LRFT, Bruno SF, Liebhold MM, Kaup F-J, Romão MAP. 1993. Contribuição ao Estudo das Herpesviroses em Callithrix sp. In: Congresso Internacional de Medicina Veterinária em Lingua Portuguesa, VI, Salvador - BA. Anais. Salvador. Comite Permanente dos Congressos Internacionais de Medicina Veterinária em Lingua Portuguesa, Pp. 210–211.
3. Mello MT de, Raick AN. 1985. Surto Fatal de Infecção Herpética em Pequeno Grupo de Callithrix jacchus. In: 2nd Congresso Brasileiro de Primatologia, Campinas - SP. Anais. Campinas. A Primatologia no Brasil, 2: 496.
4. Ott-Joslin JE. 1993. Viral Diseases in Nonhuman Primates. In: Fowler ME. Zoo & Wild Animal Medicine: Current Therapy III. Philadelphia, PA. W.B. Saunders, Pp. 674–679.
5. Pachaly JR, Werner PR, Diniz JMF. 1991. Infecção natural por Herpesvirus hominis em Callithrix jacchus jacchus Callithricidae (Thomas, 1903). Primates. a hora veterinária, Porto Alegre 61: 11–12.