Sparganosis in a Saddle-back Tamarin: Another Case of Viral-Induced Proliferation?

A saddle-back tamarin (Saguinus fuscicollis illigeri Pucheran, 1845) maintained in Oak Ridge Laboratory, Oak Ridge, Tennessee, for 6 yr was found dead in its cage. Necropsy revealed numerous small nodules in the thoracic cavity only, 1-5 mm in diameter, causing marked adhesions of thoracic organs. The cysts contained intact and degenerating cestode larvae in addition to inflammatory cells. The morphology of the larva was most consistent with that of a sparganum. Many larvae contained very basophilic accumulations of large nuclei when stained with H&E. Viral particles, averaging 200 nm in diameter, were found throughout they cytoplasm of intact and degenerating larvae. The particles had an electron-lucent core and thick shell.