Key Questions Answered
Q1. What are molecular diagnostic tests for tuberculosis?
Answer: Molecular diagnostic tests are modern laboratory tests that detect the genetic material (DNA) of Mycobacterium tuberculosis. They diagnose TB much faster and more accurately than conventional smear microscopy and can identify drug resistance at an early stage.
Q2. What is CBNAAT?
Answer: CBNAAT (Cartridge-Based Nucleic Acid Amplification Test) is a rapid molecular test that can detect TB and rifampicin resistance within about two hours. It has significantly improved early diagnosis and timely initiation of appropriate treatment.
Q3. What is Truenat?
Answer: Truenat is an indigenous, chip-based molecular diagnostic platform developed in India. It is portable, battery-operated and suitable for use even in remote areas. It detects TB rapidly and also identifies rifampicin resistance.
Q4. What is NAAT?
Answer: NAAT (Nucleic Acid Amplification Test) is a group of molecular techniques that amplify and detect the DNA of TB bacteria. Both CBNAAT and Truenat are examples of NAAT technology used under the National TB Elimination Programme (NTEP).
Q5. Who should undergo these tests?
Answer: Molecular tests are recommended for people with symptoms suggestive of TB, children, people living with HIV, seriously ill patients, suspected drug-resistant TB cases and patients with extrapulmonary tuberculosis, as advised under NTEP.
Q6. Why are molecular tests better than conventional sputum microscopy?
Answer: They are faster, more sensitive and more accurate. They can detect TB even when the number of bacteria is low and simultaneously identify rifampicin resistance, allowing doctors to start the correct treatment without delay.
Q7. Can molecular tests diagnose drug-resistant TB?
Answer: Yes. CBNAAT and Truenat can rapidly detect resistance to rifampicin, one of the most important anti-TB medicines. Early detection helps in timely referral and initiation of appropriate drug-resistant TB treatment.
Q8. Are these tests available free of cost?
Answer: Yes. Under the National TB Elimination Programme (NTEP), CBNAAT and Truenat testing is available free of cost at designated Government health facilities across India.
Q9. Do these tests replace clinical examination and other investigations?
Answer: No. While molecular tests are highly valuable, doctors may also recommend chest X-rays, culture, drug susceptibility testing or other investigations depending on the patient’s clinical condition and the site of disease.
Q10. How do molecular tests support India’s goal of TB elimination?
Answer: Early and accurate diagnosis leads to early treatment, reduces transmission in the community, detects drug resistance promptly and improves treatment outcomes. Molecular diagnostics have become one of the most important tools in India’s strategy to eliminate tuberculosis.
*Conclusion*Dr S K Arora states that if you have a cough lasting two weeks or more, fever, weight loss or night sweats, do not delay testing. Early diagnosis through modern molecular tests can save lives and help stop the spread of tuberculosis.
End TB → Early Diagnosis → Early Treatment → Better Recovery
End Tobacco. → End TB. → Save Lives.
Dr S K Arora
WHO Awardee | Senior Chest Specialist | TB Expert | Tobacco Control Advocate
