Monday, September 18, 2006

TUBERCULOSIS and modes of Transmission


Tissue response in tuberculosis represents classical example of chronic granulomatous inflammation in humans.the causative agent is tubercle bacillus or Koch s bacillus called Mycobacterium tuberculousis causes tuberculosis in the lung and other tissues of the human body. The organism is a strict aerobe and thrives best in tissues with oxygen tension like in the apex of the lung.

Mode Of Transmission

  1. Inhalation of organisms present in fresh cough droplets or in dried sputum form an open case of pulmonary tuberculosis.
  2. Ingestion of the organisms leads to development of tonsillar or intestinal tuberculosis. This mode of infection of human tubercle bacilli is from self-swallowing of infected sputum of an open case of pulmonary tuberculosis, or ingestion of bovine tubercle bacilli from milk of diseased cows.
  3. Inoculation of the organisms into the skin may rarely occur from infected postmorten tissue.
  4. transplacental route results in development of congenital tuberculosis in foetus from infected mother and is a rare mode of transmission.