Pathologic Histology of Experimental Virus Influenza in Ferrets

Abstract

The intra-nasal inoculation of influenza virus in ferrets while under ether anesthesia produced pathologic alterations in the nasal mucosa and lungs. In the former an acute inflammatory reaction appeared soon after inoculation and at first consisted of a diffuse leucocyte infiltration associated with necrosis and desquamation of portions of the epithelium; the reaction was more marked in respiratory mucosa than in olfactory mucosa. Later there was stratification of the mucosal epithelium, a decrease in leucocyte infiltration, and finally a return to normal which was almost complete by the 29th day. In the lungs there was acute bronchitis and bronchiolitis with an associated broncho-pneumonia. The lesions were at 1st chiefly exudative, while in the later stages proliferative changes were predominant. The lungs were normal in ferrets killed 29 days after inoculation. No lesions which could be definitely attributed to influenza virus were seen in mediastinal lymph nodes, heart, liver, spleen, kidneys or adrenals.