Introduction Formerly known as Pasteurella pestis. Falls in family enterobacteriaceae. Discovered in Honkong in 1894 AD by Yersin and Kitasato. Important medical species are Y.pestis, Y. pseudotuberculosis and Y. enterocolitica. Y. pestis responsible for causing plague whereas Y. pseudotuberculosis is a primary pathogen of rodents. Similarly, Y. enterocolitica causes enteric and systemic diseases. These diseases … Read more
Gonococcus is considered to be a strict human parasite. Various attempts were done to infect animals. But all had failed until recently when chimpanzees have been experimentally infected. Gonococcus is generally found only in cases of acute, chronic or asymptomatic infection. But not found in healthy carriers like meningococccus. The latter may account for 70-80% … Read more
Introduction to infection An infection is the detrimental colonization of a host organism by a foreign species. In an infection, the infecting organism seeks to utilize the host’s resources to multiply, usually at the expense of the host. The infecting organism, or pathogen, interferes with the normal functioning of the host and can lead to … Read more
Bacteria 1. very small in size. Virus 1. smaller than bacteria 2. can be seen under compound microscope. 2. can be seen only under an electron microscope. 3. shows metabolic activities. 3. do not show metabolic activities. 4. … Read more