Tuberculosis still exists in the world after so many years, despite advances in research. TB has not been eradicated, and this essay outlines a few of the main reasons for this.
Tuberculosis (TB) is caused by bacteria (Mycobacterium tuberculosis), which primarily affects the lungs. Tuberculosis is both curable and avoidable. Approximately one-quarter of the world's population is infected with tuberculosis (TB), which means they have been infected by TB bacteria but are not (yet) ill with the disease and cannot transmit it.Data from the World Health Organization (WHO) for the year 2020 says, 1.5 million people died as a result of tuberculosis.
There are numerous reasons why tuberculosis has not yet been eradicated from the world. The first and most important consideration is the mode of transmission of tuberculosis. Mycobacterium tuberculosis spreads via aerosols, resulting in a simple and quick mode of transmission between individuals. 
Another reason is the phase of latent tuberculosis infection(LTBI). The disease may not be detectable in lab tests for several months after the initial infection. Meanwhile, a person who is unaware they are infected can spread the airborne disease to others without realizing it. One-third of the world's population is thought to have "latent tuberculosis.".The World Health Organization defines LTBI as a persistent immune response to M. tuberculosis antigen stimulation in the absence of clinically manifested active TB. Preventing the progression of LTBI to active TB disease is a critical public health goal that has the potential to significantly reduce TB transmission but it is highly impossible to know who has LTBI. To achieve TB elimination goals, targeted LTBI testing and treatment of marginalized and difficult-to-access groups, as well as those at high risk of TB reactivation, is a top priority. Shorter and more effective preventive treatment regimens, more sensitive LTBI diagnostics, and novel tests to identify those at highest risk of TB reactivation will all contribute to meeting the TB elimination goals. 
Another, and perhaps the most important, reason for not eradicating tuberculosis is the emergence of drug-resistant tuberculosis. Patients with multidrug-resistant tuberculosis (MDR TB) and extensively drug resistant TB (XDR -TB) are infected with strains that are resistant to isoniazid and rifampicin.Patients with MDR and XDR strains pose a formidable treatment challenge; however, cure is often possible with early detection of resistance and the use of a properly designed regimen. The main causes of the increasing spread of resistant TB strains are inadequate medical systems, resistance amplification due to incorrect treatment, and ongoing transmission in communities and facilities. New molecular DST methods have revolutionized MDR-TB diagnosis, but they are still not widely available in resource-constrained settings. Community-based programmes that allow patients to be treated in their homes and address socioeconomic barriers to adherence can improve treatment outcomes. 
The attitude of the people and the government is the most easily explainable reason for the failure of Tuberculosis eradication. People in low-income areas have less money to purchase the necessary treatment to cure tuberculosis.People still regard tuberculosis as a taboo disease and do not disclose it to others, resulting in an increased rate of bacterial transmission. 
Tuberculosis treatment is lengthy, and many patients lose patience and do not complete the therapy or willingly discontinue it once the symptoms have subsided. This has lead to drug-resistant tuberculosis, requiring the patient to be on longer and more medications to treat it when the disease relapses.
Another blunder is the government's attitude.According to the most recent national TB patient cost survey data, nearly one in every two TB-affected households faces costs that exceed 20% of their household income. Funding in low- and middle-income countries (LMICs), which account for 98 percent of reported TB cases, is far insufficient.However, in response to declining disease incidence and prevalence rates, most countries typically cut budgets.Neglect or complete cessation of intervention activities can result in the disease re-emerging in vulnerable populations.Despite the fact that bacille Calmette–Guérin(BCG) has been in use for nearly a century, tuberculosis remains a major global problem.Obviously, as the number of cases declines, it becomes more difficult to keep tuberculosis at the top of the government's priority list. Severe critical challenges that impede effective TB control can be identified.
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