Cy-TB test

The introduction of the Cy-TB test by Kerala health authorities is a significant step in advancing the detection and treatment of latent tuberculosis (TB) in India, especially under the National TB Elimination Programme (NTEP).

Highlights of the Cy-TB Test:

1. Intradermal Test: The Cy-TB is an intradermal test, meaning that the substance is injected into the skin rather than under the skin, which makes it relatively easy and safe to administer.

2. Third-Generation Test: This is a third-generation test approved by the Central TB Division, Government of India, reflecting significant improvements in accuracy and specificity compared to older TB tests.

3. Target Population: The test is recommended for individuals aged 18 years and above, which aligns with the focus on detecting and treating latent TB among adults as part of India's strategy to eliminate TB by 2025.

4. How It Works:

   • The test involves injecting 0.1 ml doses of M. tuberculosis-specific antigens (namely ESAT-6 and CFP-10) into the skin on the inner forearm.

   • After 48-72 hours, if a raised area (induration) of 5 mm or more forms, it indicates that the person has been exposed to the TB infection.

5. User-Friendly: The test is described as highly specific, accurate, and user-friendly, meaning it can be easily conducted and interpreted, leading to more effective and timely treatment.

What is Tuberculosis (TB)?

TB is an infectious disease caused by the bacterium Mycobacterium tuberculosis, primarily affecting the lungs, but it can also affect other parts of the body. TB spreads through the air when an infected person coughs, sneezes, or spits, and it only takes a few germs to become infected.

Global Context:

• According to the World Health Organization’s (WHO) Global Tuberculosis Report 2024, India remains the country with the highest burden of TB worldwide, accounting for 26% of global TB cases.

• India is also a hub for drug-resistant TB (DR-TB) and contributes significantly to global TB deaths.

• TB is a major cause of death among people living with HIV, making it a critical issue for public health. It is also a major driver of antimicrobial resistance (AMR), which complicates treatment.

Why Cy-TB is Important for TB Elimination:

1. Enhanced Early Detection: Cy-TB is particularly useful for identifying latent TB, which is the stage when a person is infected with the TB bacteria but does not show active symptoms. People with latent TB are at risk of developing active TB later, especially if their immune system weakens.

2. Tackling the Burden of Latent TB: By identifying individuals with latent TB, it becomes possible to treat them early, preventing the progression to active TB, which is contagious and more difficult to treat. This is especially critical in India's efforts to meet the National Strategic Plan for Tuberculosis Elimination by 2025.

3. Cost-Effective and Accessible: The skin test is likely to be more affordable and accessible than other diagnostic methods, making it suitable for widespread use, particularly in rural areas, where TB is still a significant problem.

4. Part of NTEP's Strategy: The NTEP (National Tuberculosis Elimination Program) is a government initiative aimed at eliminating TB from India by 2025. The introduction of Cy-TB aligns with the broader strategy of improving detection, treatment, and elimination of TB.

Conclusion:

The Cy-TB test marks an important step towards tackling latent TB, and its introduction will likely make a significant impact in identifying and treating TB early. With the National TB Elimination Programme (NTEP)’s focus on both active and latent TB, India is on the right path to achieve its goal of TB-free India by 2025.