Early and accurate TB diagnosis is the gateway to #endTB pathway

Shobha Shukla / Bobby Ramakant *

If we are to end TB, then we have to find every person with TB and offer accurate and timely diagnosis, treatment, care and support. In other words, we have to eliminate ‘delayed or missed diagnosis’ by making “early and accurate TB diagnosis” a norm, before we can further embark on the #endTB pathway with full force. By doing so, not only people with TB will get treated early on, but we might also have a better shot at breaking the chain of infection transmission.

In 2021, 37% of people with TB could not get a TB diagnosis globally, as per the latest WHO Global TB Report 2022. India, which has the highest TB burden worldwide, could not diagnose 1 out of every 3 people with TB in 2021.

Diagnosing TB early is as important as doing it accurately

There are WHO approved and recommended molecular tests which can detect TB more accurately and early on, and can also diagnose drug resistance upfront.

But in 2021, only 1 in 3 persons with TB worldwide was diagnosed using one of the WHO approved molecular tests. In India, molecular testing was used to diagnose 1 in 5 TB patients, while the rest were diagnosed using sputum microscopy - which is an over 140 years old diagnostic tool with low sensitivity. It underperforms even more in diagnosing TB among people with HIV, children, and extrapulmonary TB (TB of body parts other than lungs).

Delay in TB diagnosis continues to be a challenge

"A lesson from those who have untimely died of TB is that if we had diagnosed them earlier, we might have saved their lives (~1.5 million people died of TB in 2021 worldwide). Late TB diagnosis continues to be a challenge. The national TB prevalence survey (2019-2021) also reinforces our experience that two-thirds of the people are not able to seek healthcare despite their TB symptoms.

We have to address the barriers that prevent people from seeking healthcare,” said Dr Rajesh Kumar Sood, District Programme Officer of National Health Mission in Kangra, the most populated district of the state of Himachal Pradesh. Dr Sood has led the TB, HIV and NCDs programmes in Kangra from the frontlines.

Taking healthcare to the doorstep

Himachal Pradesh state of India is famous for its picturesque mountains and scenic beauty. But when it comes to infectious diseases like TB, the challenge to “reach and serve the people with what they need” goes up manifold due to its hilly terrain.

If people find it difficult to reach the TB testing centres, then can point-of-care and de-centralized molecular tests reach their doorsteps?

Dr Sood’s team has been doing “active case finding” by going from door to door. They verbally screen for symptoms, and offer a TB test to those who are TB symptomatic. Sputum samples of those who live in hard to reach areas are collected by ASHA (Accredited Social Health Activist) community healthcare workers, and transported to the nearest testing centre.

"We are able to transport the samples through the national postal courier system to the sites that have molecular testing facility. However, at times, the postal courier system has a turnaround time of around 5 days. Guidelines state that the sample must reach within 72 hours. This further adds to the delay in diagnosis."

Screen everyone, not just those with TB symptoms

Verbal TB screening is not enough. The key to end TB is finding all people with TB and treating them, at a faster rate than new people getting infected and developing TB, Dr Guy Marks, a noted respiratory medicine physician and President of the International Union Against Tuberculosis and Lung Disease (The Union) had told CNS earlier this year. "If we find just a few cases of TB and treat them, then every such case is replaced by a new case. Active case finding means finding all the cases."

Himachal Pradesh, with a population of 7.64 million, had verbally screened 6.85 million people for symptoms in 2022, as per the government’s India TB Report 2023. Out of them, 0.7% had TB symptoms so were offered a TB test. Among those tested, 0.4% were diagnosed with TB.

Details matter: It is important to note that as per the government’s India TB Report 2023 only one-third of those with presumptive TB could get a molecular test in Himachal Pradesh. Most of these molecular tests were performed using one of the 47 Molbio’s TrueNat machines available in the state (almost double the number of Gene Xpert machines). At the national level, India had 3615 TrueNat machines in 2022, through which 3.48 million molecular tests for TB were performed. This is the highest number of tests done by any molecular method in the country.

"We have one molecular testing machine in all blocks of our Kangra District of Himachal Pradesh, but more capacity is needed for transitioning to upfront molecular testing for everyone. The TrueNat machines procured for COVID-19 testing, now are being used for TB testing too," said Dr RK Sood.

Out of those diagnosed with TB in Himachal Pradesh, 2.4% were of drug-resistant TB - 95% of them were initiated on treatment in 2022. Although the shorter all oral Bedaquiline-based regimen (which is less toxic and has better treatment outcomes) should be provided to everyone with drug-resistant forms of TB, only 62% of those with it could get it in Himachal Pradesh and had a treatment success rate of 82%.

Are the older people being left behind in TB response?

In India, 1 in 5 people who was estimated to have active TB disease in 2021 was over 55 years of age as per the Global TB Report of the WHO. One-third of these older persons could not get access to TB services (or were not notified to the government-run National TB Elimination Programme).

TB rate in those above 55 years of age is almost double than in others. That is why Dr RK Sood and his team try to offer the older persons upfront molecular testing. "Most of those who get diagnosed with TB due to active case finding are the older people. Moreover, at times the older persons have to wait for somebody to accompany them to the hospital, which could add to the delays. That is why we try to offer them upfront molecular testing. Although due to high sample load, sometimes supplies could be short," he said.

Preventing TB should not be forgotten

Proper infection control in homes, communities, workplaces, and healthcare settings should be a norm. “That is why we screen every incoming person at the registration counter in places that report high number of TB cases. We provide them the red coloured fast track priority pass card so that the staff can fast track them towards the care pathway. This helps us in preventing infection spread, as well as improves case detection,” said Dr RK Sood.

With support from local administration, Kangra Ni-kshay Kit (infection prevention kit) are given to the people with TB for disposal of sputum during the infectious phase of the treatment. This is intended to help reduce transmission in the homes and communities.

Every case of active TB disease comes from a pool of people with latent TB. People with latent TB do not have TB disease, are not infectious, and cannot spread the infection to others. But they may be at risk of progressing to active TB disease. TB preventive treatment protects people with latent TB from progressing to active TB disease. “Around 1500 people with latent TB have completed the full cascade of TB preventive treatment and care in Kangra with treatment success rate of 95%,” said Dr Sood.

Chest X-ray is needed to complement TB screening

Shortage of X-ray machines is another limiting factor, as a chest X-ray is needed to rule out active TB disease and confirm that a person has latent TB and not the disease. “We need more portable or handheld point-of-care X-ray machines,” shared Dr Sood.

Only 5% of those screened for TB symptoms could get a chest X-ray done in Himachal Pradesh. The national TB prevalence survey (2019-2021) shows that half of those diagnosed for TB did not have typical TB symptoms, but showed an abnormality in the chest X-ray, which led to their TB diagnosis.

Innovation

Himachal Pradesh has used innovative tools in some areas (and to a limited extent), such as handheld portable X-ray machines. In Una district these (along with molecular testing) were used to screen migrant workers.

Drones were also used for drug and sputum sample transportation in Mandi district of Himachal Pradesh. Mandi has mountainous terrain and timely transportation of samples and medicines is often a challenge. According to the India TB Report 2023, 28 drone flights took place till 31 January 2023 between Mandi and different primary health centres up to 90km away. Sputum samples were transported by drones from primary health centres to Mandi for molecular testing and TB drugs were transported back. Usage of drones reduced the transportation time and operational costs to one fourth.

Himachal Pradesh gives hope

A year after India’s National Health Policy 2017 was launched (aiming to end TB by 2025), Himachal Pradesh’s Chief Minister had announced an ambitious programme to end TB by 2023.

In 2022 Himachal Pradesh had ranked first on the National TB Index, among Indian states with over 5 million population. In 2021, Himachal Pradesh was among the 5 Indian states that had successfully reduced TB rates by 20%.

Despite this commendable progress, formidable challenges confront the state to end TB. The next 28 months will tell us to what extent the state has kept the promise to eliminate TB by 2025.