Lurking in the shadows cast by COVID, TB is poised for a deadly return
Unlike viruses, bacteria are living entities, and are capable of self-replicating inside the host body. Photo: iStock

Lurking in the shadows cast by COVID, TB is poised for a deadly return

COVID-19 has turned the world upside down, causing untold miseries to us in several aspects. Amidst the rising concerns, prompt medical services to patients suffering from other ailments — some equally life-threatening as COVID-19 — are affected severely. One such dreaded disease care that is facing a severe blow due to the ongoing pandemic is Tuberculosis (TB).

India bears one-fourth of the world’s TB disease burden. According to the World Health Organisation’s (WHO) Global Tuberculosis Report of 2019, India continues to face 4,000 TB deaths each day. While, many more cases go unreported or unattended due to lack of timely action, further complicating the statistics of the disease. Adding to the woes, lockdowns have caused massive disruption in TB services, leaving the disease management programs in the lurch.

On the other hand, “TB case notifications across India have dropped by over 50 per cent since March,” avers Professor Madhukar Pai, director at McGill International TB Centre, Canada. The pandemic has pushed away patients and new cases from self-reporting owing to the fear of the unknown and overlapping symptoms like respiratory difficulties. “This is very worrisome since undiagnosed TB can worsen patient outcomes, and increase transmission in the community,” adds Dr Pai.

The dreaded disease

Tuberculosis is a bacterial infection with a high mortality rate: more people die of this contagious disease than any other infectious agent. Just like the coronavirus, TB spreads rapidly through pathogen-laden droplets expelled from talking, sneezing, singing, or coming close to the patients.

Several strains of the bacteria belonging to the group mycobacterium can infect any organ in the body. However, Mycobacterium tuberculosis is the highly virulent strain that affects the lungs causing the rampant pulmonary Tuberculosis. Just as the coronavirus, TB spreads rapidly from person to person.

Unlike viruses, bacteria are living entities. They are capable of self-replicating inside the host body. Most often, the bacterial growth is contained by our immune system. However, the pathogen also resides in a dormant state in the body without causing any symptoms. Whenever the body’s immunity is compromised due to other illnesses or some medications, the bacteria resurfaces, attacking the body and creating full-blown symptomatic Tuberculosis.

Dormant or Latent TB is an asymptomatic condition and does not spread from person to person. However, once diagnosed, Latent TB should also be treated with a course of antibiotics. Without medical intervention, nearly half of asymptomatic cases progress to the active condition in a few years. People exposed to TB patients, or to environments where TB is prevalent are susceptible to latent Tuberculosis.

On the other hand, the red flags indicative of an active TB infection are persistent cough, blood-stained sputum, fever, chest pain and debility. When diagnosed, TB requires immediate medical attention, involving a chest X-ray, and sputum tests. Thankfully, the disease is entirely curable with multiple antibiotics, albeit the treatment duration being long term.

The challenges

Despite the availability of a cure and free distribution of medicines at the primary health centres for the patients, numerous challenges arise from time to time in eradicating the disease. Underdeveloped and developing nations bear the brunt of this consumption disease. They are often severely limited by socio-economic reasons such as poor sanitation and personal hygiene, diagnostic expenses, and lack of awareness about the condition or the treatment. Rapid point of care treatment is still elusive to many, especially in remote regions.

Besides, an emerging concern is the growing resistance of the bacteria to antibiotics. Factors such as irregularity or discontinuation of the medicines, poor drug quality, wrong dosage, insufficient treatment period or lack of drug supply govern the development of drug-resistant strains. Such a situation diminishes options for effective treatment, thereby increasing the chances of a relapse of the disease. WHO reports that for the year ending 2018, India recorded two million new and relapsed cases.

Strategies and research strides

India has been battling Tuberculosis for fifty years, despite implementing several TB control programs. On the other hand, India is also a significant contributor to TB research. For the past few years, scientists are aggressively looking for better, economical, and portable TB diagnostic devices. In parallel, research strides in targeted therapies like vaccines, gene therapy, treatment tracking and effectiveness of care with advanced technologies, is helping in taming the disease.

Molecular analysis of the sputum sample is a standard method for TB detection. Early diagnosis of presumptive TB is a crucial step in arresting the disease spread. GeneXpert is a highly reliable and standardised molecular analysis tool often sought after for screening of TB. This highly advanced machine is set up widely across India. However, the testing cost (about ₹1,500) is not a viable option for many in impoverished and rural areas — from where the disease incidences are more. Also, the infrastructural costs of the machine are high, and it requires trained personnel to operate it.

To overcome these difficulties, the National Strategic Plan for TB of 2017-2025 encouraged the development of innovative diagnostic tools. One among them the MolBio kit proved its mettle in being on par with GeneXpert. MolBio TB kit is a portable device that works on the molecular diagnostic method of PCR technology. It can accurately detect active TB infection from a single sputum sample. Moreover, the equipment is easy to operate, checks for drug resistance and gives the results in less than two hours. The demonstrated merits of the kit earned recognition by WHO and are now widely distributed as a primary TB diagnostic tool across Asia.

To cite another example, FLIPP-NAAT is a promising diagnostic device that draws attention. The prototype, released recently, is a compact strip-like device that can be stacked and transported easily in TB surveillance vans to penetrate into far-flung regions. FLIPP-NAAT has the potential to drastically reduce TB screening costs as the design uses minimal reaction agents for testing. Tiny reaction wells hold dried fluorescent reagents which react with the infectious bacterial DNA in the sputum samples. When the pathogen is detected, the chemical reaction gives off a green glow. The radiation is identified with a simple UV lamp and a mobile camera. Associated software and applications give a simple readout.  

The biggest casualty

Many such relentless and innovative research advances came to a rude halt due to the novel coronavirus outbreak. The world shifted gears to tackle the devastating challenges from the pandemic, adversely disrupting TB services. The impact pushed the treatment, awareness drives, research and patient care to the backseat.

“As lockdowns and restrictions ease, there is a huge surge in people seeking TB and COVID care,” says Dr Pai. The pandemic is overwhelming the medical services such that TB wards and hospitals have turned into COVID centres. The public sector is still dealing with the epidemic, while the private sector is not functioning at normal capacity. There is an overall reluctance to treat patients with cough and fever, while the treatment expenses are mounting.

“It is critical for the National TB Elimination Programme to resume routine TB services. There is an urgent need to integrate TB and COVID-19 testing, and be creative about engaging the private health sector to augment public TB services,” suggests Dr Pai.

Lurking in the dark, Tuberculosis is silently spreading its tentacles, poised to consume the world in its deadly grip, yet again. It is time to make haste and gain ground before this fatal disease derails the many decades of painstaking efforts made in containing it.

Read More
Next Story