Tuberculosis resurges as leading infectious disease killer: Know all about the condition

According to the Global Tuberculosis Report 2024 released by the World Health Organisation (WHO) on October 29, approximately 8.2 million people were newly diagnosed with tuberculosis (TB) in 2023 - the highest number recorded since WHO began global monitoring in 1995. This is almost a 9 per cent increase from 7.5 million cases reported in 2022, leading to TB returning to its place as the top infectious disease killer in 2023, which was temporarily occupied by Covid-19. Approximately 1.25 million people died due to TB last year.

Another worrisome finding in the report is that the global burden of TB cases lies primarily in 30 countries, with India leading at 26 per cent, followed by Indonesia (10 per cent), China (6.8 per cent), the Philippines (6.8 per cent) and Pakistan (6.3 per cent).

As the prevalence of TB raises alarms and public health systems globally strive to combat the disease, mid-day.com speaks to Dr. Kamlesh Pandey, Consultant Chest Physician, Wockhardt Hospitals, Mira Road, and Dr. Pujan Parikh, Consultant - Pulmonary Medicine, Sir HN Reliance Foundation Hospital, Mumbai, who explain the causes, symptoms, effects, and treatment of this global health burden.

What is Tuberculosis and how is it caused? Is it a chronic disease?
Pandey: Tuberculosis is caused by a bacteria called Mycobacterium Tuberculosis. This bacteria is very common in India. People who get infected with this bacteria do not always develop this disease. It remains latent in the body, and whenever immunity goes down, it can evolve into a disease. This is called latent TB.
TB is a chronic disease. In patients left untreated, it behaves like a disease and gradually can spread to other organs as well.

Parikh: Tuberculosis is an infectious disease caused by a bacteria called Mycobacterium Tuberculi. TB infection is broadly classified into pulmonary - when lungs are involved (85%), and extrapulmonary, when organs other than lungs are involved (15%).

How does TB affect the body?
Pandey: TB can affect multiple systems of the body. The most common form of TB is pulmonary TB, in which the bacteria affect the lungs. But there is also brain TB, spine TB, abdominal TB, etc.

Parikh: TB can affect any organ of the body. In India, 85 per cent of TB cases are related to the lungs and 15 per cent other organs. TB causes necrosis of the affected organ.

What are some symptoms of TB that one must look out for?
Pandey: The symptoms appear depending on the organ system involved. For example, if it's brain TB, a person can have persistent headaches, vomiting, or even develop seizures. If it is pulmonary TB, a person can get chronic fever, weight loss, blood in sputum, etc.

Parikh: Common symptoms of TB are persistent cough for more than 3 months, unexplained weight loss, loss of appetite, persistent low grade evening rise fever, chest pain, and occasionally blood in sputum. When organs other than the lungs are affected, TB gives rise to symptoms related to that organ.

Is there any group of people who are more vulnerable to the disease?
Pandey: Any patient who is immunocompromised, i.e., someone whose immunity is on the weaker side, is more at risk. This weak immunity can be due to multiple factors, like the presence of other chronic diseases like diabetes, chronic kidney or lung diseases, etc. In our country, diabetes is on the rise, which is a major risk factor for TB. Another important risk factor for TB is low body mass index (BMI).

Parikh: Immunocompromised patients like HIV patients, patients on chemotherapy, and diabetics are more vulnerable to TB.

How can one differentiate between common cold and TB symptoms?
Pandey: TB develops gradually, so symptoms appear over a period of time. They gradually start losing weight and develop a cough that is not getting treated even with medications.

On the other hand, common cold or cough develops acutely. With medications, people recover within 7-10 days.

Parikh: Symptoms of the common cold usually settle in a few days, whereas symptoms of TB persist for long, like cough, which persists for more than 3 months even after taking routine medications. Along with cough, weight loss, loss of appetite, and persistent low-grade evening rise fever are also found in TB infection.

How dangerous can TB prove to be? Is it treatable?
Pandey: If TB is diagnosed early, it is usually 100 per cent treatable. But a lot of times, diagnosis is delayed. Complications of TB start appearing as it starts affecting multiple organs. There's another case where the bacteria is resistant to the commonly-used anti-TB medications. These cases are difficult to treat and need longer treatment.

If untreated or diagnosed at a dangerous stage, TB can lead to mortality.

Parikh: TB can severely damage lungs, leading to fribrobronchiectasis. Untreated TB can lead to infertility also. TB is actually one of the most common causes of infertility in India. Untreated TB can even lead to the death of the patient.

The disease can be treated if proper treatment as per drug sensitivity is started on time.

Can TB be prevented? If yes, please share some tips.
Pandey: TB is a communicable disease. If active TB patients are diagnosed early and treated, that is the best form of prevention for other people. Those who are diagnosed should follow proper cough hygiene, like covering the mouth with a mask or handkerchief. Active screening of active or latent TB symptoms and subsequent treatment is important.

For the common public, focusing on nutrition is extremely important. What we see is that a lot of young people skip breakfast to go for classes and work. It compromises their immunity. In my practice, I have found a lot of young, college-going people getting TB, and this has been a prevailing risk factor.

Parikh: Keeping good hygiene, taking nutritious food, and wearing a mask in crowded places helps to reduce the risk of getting a TB infection.