Eradication of indigenous poliomyelitis in Canada: impact of immunization strategies.

During the period 1950-1954, surveillance for paralytic poliomyelitis in Canada revealed an average of 1,914 cases (13.2 cases per 100,000) annually. The licensing and widespread use of inactivated poliovirus vaccine (IPV) in 1955 coincided with a marked decline in disease rates.

Presence of bacterial glycocalyx and fimbriae on Pasteurella haemolytica in feedlot cattle with pneumonic pasteurellosis.

This investigation was conducted to determine if Pasteurella haemolytica within feedlot cattle affected by pneumonic pasteurellosis express fimbriae (pili) and bacterial glycocalyx. Bacteriological culture of pulmonary tissue from three calves with fibrinous pneumonia resulted in heavy growth of P. haemolytica.

Electron microscopic examination of cells of Pasteurella haemolytica-A1 in experimentally infected cattle.

Several modern electron microscopy techniques were used to examine Pasteurella haemolytica (biotype A, serotype 1) (strain B122) recovered from experimentally infected cattle and in situ within the lung tissue of experimentally infected cattle. Glycocalyx four to five times thicker than that seen on P. haemolytica grown in vitro was evident on bacterial cells recovered from live infected calves by pulmonary lavage.