About Subclinical Tuberculosis

Context:

Subclinical Tuberculosis (TB) is a growing concern in India, contributing to the slow decline in TB incidence rates despite advances in detection and treatment. 

Relevance:

GS II: Health

Dimensions of the Article:

1. Subclinical Tuberculosis:
2. About Tuberculosis
3. India’s TB Elimination Target: Goals and Challenges
4. Efforts to Achieve TB Elimination Target of 2025 in India

Subclinical Tuberculosis:

• Subclinical tuberculosis (TB) is a type of TB infection where the affected individuals show no common symptoms like a persistent cough, making it more challenging to detect than active TB.
• It is typically identified not through standard symptom-based screenings but via more advanced methods such as chest X-rays or molecular diagnostics.
• According to the National TB Prevalence Survey from 2019 to 2021, subclinical TB constitutes 42.6% of cases, with Tamil Nadu reporting a similar rate of 39%.
• Individuals with subclinical TB are asymptomatic yet capable of transmitting the bacteria to others, posing a hidden risk of spreading the infection.
• A significant number of subclinical TB cases are found in countries with high TB burdens like India, where many cases remain undetected, perpetuating the disease’s spread.
• Countries such as Vietnam have effectively lowered TB rates by implementing widespread screenings using X-rays and molecular tests that do not depend on symptom presentation.
• For a country like India, adopting large-scale, systematic screening strategies including the deployment of mobile units and increased community involvement is essential.
• Subclinical TB significantly contributes to the slow reduction in overall TB rates as many cases go unnoticed and untreated.

About Tuberculosis

• TB remains the world’s deadliest infectious killer.
• Each day, over 4000 people lose their lives to TB and close to 30,000 people fall ill with this preventable and curable disease
• TB is caused by bacteria (Mycobacterium tuberculosis) that most often affect the lungs.
• Transmission: TB is spread from person to person through the air. When people with TB cough, sneeze or spit, they propel the TB germs into the air.
• Symptoms: Cough with sputum and blood at times, chest pains, weakness, weight loss, fever and night sweats.
• Treatment: TB is a treatable and curable disease. It is treated with a standard 6 month course of 4 antimicrobial drugs that are provided with information, supervision and support to the patient by a health worker or trained volunteer.
• Anti-TB medicines have been used for decades and strains that are resistant to 1 or more of the medicines have been documented in every country surveyed.
• Multidrug-resistant tuberculosis (MDR-TB) is a form of TB caused by bacteria that do not respond to isoniazid and rifampicin, the 2 most powerful, first-line anti-TB drugs. MDR-TB is treatable and curable by using second-line drugs.
• Extensively drug-resistant TB (XDR-TB) is a more serious form of MDR-TB caused by bacteria that do not respond to the most effective second-line anti-TB drugs, often leaving patients without any further treatment options

India’s TB Elimination Target: Goals and Challenges

India has set an ambitious target of eliminating tuberculosis by 2025, five years ahead of the global sustainable development target of 2030. Here are the goals and challenges in achieving this target:

• Target Goals: India’s national strategic plan 2017-2025 aims to report no more than 44 new TB cases or 65 total cases per lakh population by 2025. The plan also aims to reduce TB mortality to 3 deaths per lakh population by 2025 and eliminate catastrophic costs for affected families.
• Current Incidence: The estimated TB incidence for 2021 stood at 210 per lakh population. However, achieving the target is a big task as the plan had envisaged an incidence of only 77 cases per lakh population by 2023.
• Mortality: The estimated TB mortality for the year 2020 stood at 37 per lakh population, which is higher than the 2025 target of 3 deaths per lakh population.
• Catastrophic Costs: The plan aims to reduce catastrophic costs for the affected family to zero. However, the report states that 7 to 32 per cent of those with drug-sensitive TB, and 68 per cent with drug-resistant TB experienced catastrophic costs.
• Challenges: India faces several challenges in achieving the TB elimination target, including inadequate funding, weak health infrastructure, low awareness, and poor treatment adherence.
• End TB Strategy: The goals are in line with the World Health Organisation’s End TB strategy that calls for an 80% reduction in the number of new cases, a 90% reduction in mortality, and zero catastrophic cost by 2030.

Efforts to Achieve TB Elimination Target of 2025 in India

• Active Case Finding: The government is actively looking for TB cases among vulnerable and co-morbid populations and screening for it at health and wellness centers.
• Notification System: A Ni-kshay portal has been established to track notified TB cases, and the private sector has been called upon to notify all TB cases.
• Improved Diagnostic Tests: The pandemic has led to improved access to more accurate molecular diagnostic tests like CB-NAAT and TureNat, with 4,760 molecular diagnostic machines covering all districts of the country. Additionally, 79 line probe assay laboratories and 96 liquid culture testing laboratories have been set up for the diagnosis of multi and extremely drug-resistant TB.
• Universal Drug Susceptibility Test: The government has implemented a universal drug susceptibility test, which determines antibiotic susceptibility for all newly diagnosed cases, ensuring patients are given effective treatment from the outset.
• Community Engagement Program: The government launched a community engagement program in which Ni-kshay mitras adopt TB patients and provide them with monthly nutritional support. So far, 71,460 Ni-kshay Mitras have adopted about 10 lakh TB patients under the program.

-Source: The Hindu