Tuberculosis (TB) is one of the commonest infectious diseases in the world today, with over 8 million new cases and 2 million deaths occurring annually. India accounts for about a quarter of the global TB burden. Worldwide India is the country with the highest burden of both TB and multi drug resistance (MDR) TB. There are an estimated 79,000 multi-drug resistant TB patients among the notified cases of pulmonary TB each year. India is also the country with the second highest number (after South Africa) of estimated HIV associated TB cases. In 2016 an estimated 28 lakh cases occurred and 4.5 lakh people died due to TB infection.  There are many TB cases in rural population remain either undiagnosed/inadequately diagnosed or unaccountably. It may be due to lake of awareness among the people in India.

Two deaths occur every three minutes from TB in India even today. Major challenges to control TB in India include poor primary health-care infrastructure in rural areas of many states. Surprisingly, in India, people are still under the impression that TB is a disease of poor people, mostly of those living in slums. The rich and affluent persons need to know that their cooks/servants/drivers can be asymptomatic carriers of this deadly disease, right in their mansions, and hence they can potentially get infected with TB even without stepping into these slums. The consumption of unpasteurized milk or dairy products made from raw milk is another potential source of TB for humans, as there is ample evidence that bovine TB (Mycobacterium bovis) gets transmitted to humans. Tuberculosis disease spread from person to person through the air. TB usually affects the lungs. TB can also affect other parts of the body, such as the brain, the kidneys or the spine. In March 2017 the Government of India (GoI) shows measure concern about the deadly infectious disease like TB and announced  new aim/objective which eliminate it by 2025.

Symptoms.

The tuberculosis infection can be detected in early stage of infection by enhancing the awareness among the people. Its general symptoms may include feeling weak or sick, weight loss, fever and/or night sweats. Sometimes parasites may enter into latent phase of infection where individual has bacterial infection but no tuberculosis symptoms. It is also known as latent tuberculosis.

The TB usually affects the lungs and it can also affect other parts of the body. However it depends upon the stage of tuberculosis infection and the symptoms will vary accordingly. When parasite infection is not control by proper treatment on time, it can spread to other parts of the body through the bloodstream like, bone, brain (leads to Meningitis), liver and kidneys, where it can impair the waste filtration functions and lead to blood in the urine.

Diagnosis.

The tuberculosis can be analyzed by specialized doctor, which check the lung and swelling of lymph nodes. The most common diagnostic test for TB is a skin test where a small injection of tuberculin is given in the forearm. The injection site is checked after 2-3 days. The site may be hard, red bumb swollen up to specific size in positive infection. Unfortunately, the skin test is not 100 percent accurate and has been known to give incorrect readings. It must be reconfirmed by other alternative test like Blood tests, Chest X-rays, and Sputum tests. MDR-TB is more difficult to diagnose than regular TB.

• Sputum examination - Samples of mucous and phlegm are checked for the presence of bacteria.
• Chest X-ray - This uses radiation to create an image of lungs. In TB infection, there are changes in the structure of lungs, which of lungs, are visible on the X-ray.
• Drug susceptibility testing - It provides a definitive diagnosis of drug- resistant TB.
• CBNAAT (Cartridges Based Nucleic Acid Amplification Test) - CBNAAT is used for early diagnosis of MDR-TB and TB in high risk population such as presumptive TB cases in PLHIV (people living with HIV), EP-TB (extra-pulmonary TB) and pediatric populations.  The CB NAAT machines have been placed at most of the districts in the country at headquarter or Medical College, ART Center or major Pediatric hospitals.

Treatment.

The five basic or "first line" TB drugs are: Isoniazid, Rifampicin, Pyrazinamide, Ethambutol and Streptomycin. These are the TB drugs that generally have the greatest activity against TB bacteria and they are core to any TB drug treatment program shown in table 1. Streptomycin is no longer considered as a first line drug by ATS/IDSA/CDC because of high rates of resistance. The second line drugs are considered as the reserved therapy for tuberculosis treatment. These drugs are often used in special conditions. When situations like resistance to first line therapy, extensively drug-resistant tuberculosis (XDR-TB) or multidrug-resistant tuberculosis (MDR-TB) arise, the second-line drugs Amikacin, Kanamycin etc are implemented for the treatment of tuberculosis. It may be less effective than the first-line drugs (e.g. p-aminosalicylic acid); or, it may have toxic side-effects (e.g. cycloserine); or it may be unavailable in many developing countries (e.g. fluoroquinolones). These drugs may be considered "third-line drugs" and are listed here either because they are not very effective or because their efficacy has not been proven.

Table 1. Drug used in clearance of mycobacteria

Prevention.

Tuberculosis transmission can be prevented by improving the healthcare facilities. It requires early identification, isolation, and treatment of patients with active TB disease. Recommended infection control strategies to reduce TB transmission depend on the prevalence of active TB in the patient population and the resources available to implement control programs. Unfortunately, the areas with the greatest need for TB infection control policies often have the fewest resources for creating and maintaining effective control programs. Many inexpensive interventions can significantly reduce the risk of TB transmission in healthcare settings.

Future expectation.

To aware the people about basic aspect of tuberculosis and its infection which make India TB free by 2025. The basic knowledge about the infection will make people confident to treat the tuberculosis without generating gap against the expert consent.

* This article  is for education purpose only.