EXPERIMENTAL-INFECTION OF GUINEA-PIGS WITH VENEZUELAN HEMORRHAGIC-FEVER VIRUS (GUANARITO) - A MODEL OF HUMAN-DISEASE

Venezuelan hemorrhagic fever (VHF), a newly described disease caused b y an arenavirus (Guanarito), has resulted in multiple human deaths in Venezuela. To develop an animal model of this disease, strain 13 and H artley strain guinea pigs were inoculated subcutaneously with Guananto strain 95551 of arenavirus in a pilot study to determine susceptibili ty of the species to the virus. All animals were killed when moribund 12-14 days following inoculation. Animals were necropsied and tissues were fixed and examined by both light and electron microscopy. Viral a ntigen was demonstrated in the tissues by immunohistochemistry at both the light and electron microscopic levels. Lesions were characterized by single cell necrosis of epithelium of the gastrointestinal tract, interstitial pneumonia, lymphoid and hematopoietic cell necrosis, and the presence of platelet thrombi in occasional blood vessels associate d with hemorrhage. Viral antigen was demonstrated in lymphoid tissues and macrophages, endothelial cells of multiple organs, pulmonary epith elium epithelium of the gastrointestinal tract, and in miscellaneous o ther tissues and cells. Intact virions and typical arenavirus inclusio ns were demonstrated by immunoelectron microscopy in these tissues. Ba sed on these findings, the guinea pig appears to be a valid animal mod el of the human disease.