Changes in the kidney structure in outbred and inbred male BALB/c mice were analyzed in the acute period after infection with influenza viruses A/H5N1 (10 MLD50; 10 days) and A/H1N1 (1 MLD50; 30 days). Antibodies to influenza viruses of both strains were most often expressed by endothelial cells of the glomeruli and arterioles and were rarely expressed by mesangiocytes and tubule epithelial cells. In the kidney, destructive processes induced by viruses and by ischemia due to massive blood vessel thrombosis. Mesangiocytes expressed factors, indicating that they could be qualified as M1 and M2 macrophages. Kidney destruction was more significant after infection of mice with the A/H5N1 virus, but in both experiments cell infiltrates were actually absent, probably due to blood vessel thrombosis and limited possibility of migration of mononuclear phagocytes and lymphocytes to the kidney.