Clinical signs of infected seals included debilitation, muscle spasms, ocular and nasal exudation, and sneezing. Necropsies performed in June 2000 on eight Azerbaijan seals revealed microscopic lesions, including bronchointerstitial pneumonia, encephalitis, pancreatitis, and lymphocytic depletion in lymphoid tissues. Similar lesions were also discovered on four seals from Kazakhstan. "Morbillivirus" antigen was also detected in multiple tissues, including lung, lymph nodes, spleen, brain pancreas, liver, and epithelial tissue of the reproductive, urinary, and gastrointestinal tracts. Such tissue lesions are characteristic of distemper in both terrestrial and aquatic mammals.