The New Nation - Internet Edition

Tia

Feature: Tuberculosis

Name type of causative organism: The cause of tuberculosis is Mycobacterium.

tuberculosis (MTB) which is a slow growing ·aerobic bacterium that divides every 16 to 20 hours.

Is it a newly evovled disease: No. Tuberculosis has affected people since ancient times;

archaeological evidence based on characteristic damage to bones suggests since at least 5000-4000 BC.

Number of deaths per year worldwide : Tuberculosis (TB) is the greatest infectious disease killer killing approximately 2 million adults and about 100 000 children. Symptom: Bloody coughing/bleeding from the lungs, fever, paleness prolonged wasting, sputum, night sweats, loss of weight and tiredness.

Route of transmission:

(i) droplet infection e.g. coughing, sneezing, talking.

(ii ) via infected food

( iii ) faces

(iv) water

( v ) infected hands

( vi ) transmitted by milk

( vii) transmitted by flies

Reservoir of infection: The bacteria causing tuberculosis (TB) can be transmitted from cows to people in infected milk. Nevertheless, in developed countries TB (of the lungs) is now nearly exclusively spread through person-to-person contact, this has been accomplished by eradicating TB from cattle herds. Type of cells affected: It commonly affects the lungs i.e. necrosis of lung epithelial cells (pulmonary TB) but can also affect the central nervous system (meningitis), lymphatic system, circulatory system (Miliary tuberculosis), genitourinary system, bones and joints.

Time course of active disease: Tuberculosis of the lungs normally results in no or minimal symptoms in its primary stages because it is contained by the immune system, and the lesion, called a tubercle, becomes calcified. The course of this disease is slow, and it may take months or years to develop. In others it may break out again and become' active years later - when immune defenses are low. If untreated it can progress until large areas of the lungs and other organs are destroyed.

What treatment is available : Antitubercular chemicals combat TB in several ways .i.e. measures to prevent infection before or after exposure to TB organisms, treatment of the infected patient and its adverse conditions.

Is a vaccine available? Yes. BCG-vaccination