Department of Microbiology,

Anand Diagnostic Laboratory

Tuberculosis (TB) is a disease caused by bacteria that are spread through the air from person to person. Tuberculosis is caused by Mycobacterium tuberculosis and is one of India’s major public health problem. India remains to be a high burden Tuberculosis (TB) country contributing to 23%

of all TB cases in the World, In India, two deaths occur every three minutes from TB. Surprisingly in India, people are still under the impression that TB is a disease of poor people, but it is not so.

The TB bacteria spreads when a person with TB disease coughs, spits, sings, sneezes or speaks. People nearby may breathe in these bacteria and become infected.

Active TB is basically the ongoing disease i.e.; patients are infected with Mycobacterium tuberculosis and shows symptoms for TB (80-90% pulmonary (affecting lung) and 10-20% extrapulmonary (affects other parts of the body such as the kidney, brain, spine and bones)) while Latent TB infection(LTBI) is the one in which the person acquires and carries the bacilli from diseased contact but does not show symptoms of TB disease, but may still need treatment.

TB bacteria most commonly grow in the lungs and can cause symptoms such as:

  • A bad cough that lasts 2 weeks or longer

Drug-resistant TB can occur when the drugs used to treat TB are misused or mismanaged.

  • People do not complete a full course of TB treatment

Drug-resistant TB is more common in people who

  • Do not take their TB drugs regularly and who don’t complete the Course of treatment

Diagnosis of Tuberculosis:

  • Microscopic examination of Sputum: Early morning sputum sample is recommended and least 2 samples of sputum to be tested.
  • Chest X-ray: It is used as a screening tool for diagnosis.
  • Nucleic acid amplification tests (NAAT)- GeneXpert /Line probe Assay: This is a group of tests that use either the polymerase chain reaction (PCR) technique to detect Mycobacterium tuberculosis complex and drug resistant genes for First and second line drugs.

Morbidity of illness, financial burden, access issues, social stigma, confidentiality issues and adverse reactions to drugs often makes TB care a complex issue and these factors often determine patient’s adherence to TB treatment.

The Directly Observed Short Course Strategy (DOTS) using a thrice-weekly regimen for six months has been the backbone of country’s TB programs for last two decades. The Direct Observation of Treatment (DOT) is an important component of the strategy and is an attempt to improve adherence by active monitoring and recording of the consumption of each drug dose by an ‘observer’ acceptable to the patient and the health system.

Prevention of Tuberculosis:

  • Vaccination: All newborn and infants should be given the Bacillus Calmette–Guérin (BCG), the vaccine to protect them against TB. The vaccine prevents infections and to protect half of the infected individuals from developing active TB.


1.World Health Organization, Global tuberculosis control: WHO report

2.Anti-tuberculosis resistance in the world: WHO

3.RNTCP guidelines

Published On: February 19th, 2021 / Categories: General Health /

Recent Posts