Tuberculosis in India

Tuberculosis is now considered to be one of the most widespread human infections today (Brighenti & Lerm, 2012). As of 2011, the World Health Organization found that there were 1.4 million deltas due to tuberculosis. Three hundred thousand of those deaths were in India (Kolappan et al., 2013). There are an estimated 2.3 million new cases every year in India alone. India is now "the highest tuberculosis burden country in the world" (Rao et al., 2012). In 2010, it is estimated that citizens of India accounted for 21-26% of all the tuberculosis cases in the entire world (Rao et al., 2012; Kamineni et al., 2012). From 1955 to 1958, researchers at the time found that there were 400 positive tuberculosis cases per every 100,000 people and that there were approximately 1.5 million infectious cases present in the community (Rao et al., 2012). Since the 1950's there have been numerous attempts to control and eradicate the incidence of tuberculosis, but few have succeeded (Rao et al., 2012).

In an effort to provide a baseline for future studies to work against, researchers Rao et al. (2012) studied "the prevalence of bacteriologically positive tuberculosis in Jabalpur, a district in central India" (Rao et al., 2012). Researchers used a community-based cross-sectional survey and a stratified cluster sampling design to find an appropriate sample for the study. With a sample size of about 90,000 individuals at least fifteen years of age, researchers carried out a house-to-house census and recorded the residence of anyone living at a particular home for more than 6 months (Rao et al., 2012). Researchers collected information pertaining to age, sex and other demographic information (Rao et al., 2012). Next, researchers questioned all individuals above the age of fifteen years old to determine if they were experiencing any symptoms of tuberculosis such as persistent coughing for two or more weeks, chest pain for one or more months, fever for one or more months, and hemoptysis (coughing up blood) at any time in the past six months (Rao et al., 2012).

After pre-screening for tuberculosis symptoms, researchers approved anyone experiencing these symptoms as eligible for sputum collection (Rao et al., 2012). Eligible participants were asked for two sputum samples, which were processed and analyzed (Rao et al., 2012). Of the 99,918 participants surveyed, 7,916 (8.3%) reported symptoms congruent with tuberculosis (Rao et al., 2012). Of the symptomatic participants, 7,533 gave sputum samples for testing and 221 of these participants were found to be bacteriologically positive for tuberculosis (Rao et al., 2012). The researchers concluded that the current prevalence of tuberculosis in Jabalpur, a district relative in density and population composition to other districts in India, is 255.3 cases of tuberculosis for every 100,000 people (Rao et al., 2012).

In response to the overwhelming number of cases of tuberculosis and resulting deaths, the World Health Organization recommended a new program intended to treat and monitor people suffering from tuberculosis (Kolappan et al., 2013). The program, established in 1997, is based on the Directly Observed Treatment Supervised program, or DOTS for short, and is called the Revised National Tuberculosis Control Programme (RNTCP) (Kolappan et al., 2013). The RNTCP utilizes a systems approach to providing care (Lal et al., 2011). The Phases of the program include: "1) local mapping of all care providers in a systematic manner; 2) prioritization of providers most likely to contribute to TB case notification and treatment; 3) agreement on the provider-specific task-mix; 4) setting up of a surveillance system to measure the contribution of the different providers; and 5) implementation and evaluation of the results of collaboration prior to further expansion" (Lal et al., 2012). Preliminary research showed that the DOTS system has had desired effects in decreasing the prevalence of tuberculosis infection in recent years (Kolappan et al., 2012). More recently, in a study by Kolappan et al. (2013), researchers surveyed a sample of patients being treated by the DOTS-based RNTCP program in Tiruvallar. The purpose of the survey was to determine the trends in tuberculosis prevalence and if the disease was being controlled (Kolappan et al., 2013). Essentially, the researchers were evaluating whether or not the DOTS-based RNTCP program was operating as intended.

Researchers surveyed citizens over the course of four rounds: 1999-2001, 2001-2003, 2004-2006, and 2006-2008 (Kolappan et al., 2013). In each round, the researchers surveyed samples proportionate to the Tiruvallar population of the given census years. Participants were at least fifteen years of age. For the survey, specially trained field investigators interviewed the participants (Kolappan et al., 2013). In addition to the survey interview, the participants were given a chest radiograph to screen for tuberculosis (Kolappan et al., 2013). The radiograph results were read by two readers to ensure accuracy and, in the case that the readers disagreed, a third reader was involved to make the final decision. Furthermore, "sputa were collected from those with abnormal radiograph and/or presence of chest symptoms, and examined by direct smear culture" (Kolappan et al., 2013).

Researchers found that the prevalence of cases of culture-positive tuberculosis was 607 in the first round, 454 in the second round, 309 in the third round, and 388 in the fourth round out of samples of 100,000 people per round (Kolappan et al., 2013). Prevalence rates for cases of smear-positive tuberculosis were 326 in the first round, 259 in the second round, 168 in the third round, and 180 in the fourth round (Kolappan et al., 2013). The results show an annual decrease of 12.4% per year for culture-positive tuberculosis and 12.2% per year for smear-positive tuberculosis for the first three rounds (Kolappan et al., 2013). However, the fourth round showed a small increase in cases of tuberculosis, indicating that the downward trend was not consistent and had been interrupted by some factor.

In the first four years of the seven-year study, the rate of new cases of smear-positive tuberculosis was 75 new cases out of a sample of 100,00 per year (Kolappan et al., 2013). In the final three years of the study, the rate of new cases of smear-positive tuberculosis was 49 new cases out of a sample of 100,000 (Kolappan et al., 2013). This indicates that although the new cases of tuberculosis were declining towards the end of round three and into round four, the existing cases were not being well-enough managed or cured, resulting in round four's higher rate of positive cases of tuberculosis.

Researchers reported no methodological differences over the course of the entire study (Kolappan et al., 2013). Therefore, the cause of the lack of improvement in reducing the number of positive cases of tuberculosis must lie with the program itself or the form of transmission of the illness. Kolappan et al. (2013) state that "despite the average annual success rate (78%) in this tuberculosis unit being lower than the expected rate of 85%, the implementation of DOTS was followed by a substantial decrease in the prevalence of pulmonary tuberculosis over the seven and a half year period" (Kolappan et al., 2013). In order to improve and continue decreasing the number of cases of tuberculosis, the DOTS program must be maintained with "vigilant supervision" (Kolappan et al., 2013).

Tuberculosis is caused by Mycobacterium tuberculosis, a bacterium that "affects the lungs and is characterized by cough with bloody expectorations associated with fever, night sweats and weight loss" (Brighenti & Lerm, 2012). Tuberculosis can also be extrapulmonary, occurring outside of the lungs, and be found anywhere in the body, such as in the lymph nodes, abdomen, bones, joints, and the central nervous system, for example. While an individual may be infected with tuberculosis, the individual may not be experiencing symptoms (Brighenti & Lerm, 2012). Active tuberculosis in which symptoms are present occurs in 5-10% of individuals infected with tuberculosis. At present, researchers estimate that "about one third of the world population are carriers of TB infection, which constitutes an enormous reservoir for potential spread of disease" (Brighenti & Lerm, 2012).

The activity of tuberculosis is closely related to the immune system of the host. As the host's immune strength shifts, the tuberculosis bacterium goes through different changes, attempting to progress from latent to active (Brighenti & Lerm, 2012). Mycobacterium tuberculosis is a capsular-shaped cell with a waxy cell wall, which allows it a form of protection within the body, causing the bacterium to be extraordinarily resilient. Furthermore, Mycobacterium tuberculosis can adjust the thickness of the cell wall in response to stressors such as the host's immune system, drought, low pH and antibiotics (Brighenti & Lerm, 2012).

Mycobacterium tuberculosis most commonly infects the body by being inhaled in droplets of moisture that have been expelled by an infected individual (Brighenti & Lerm, 2012). Therefore, the vector for Mycobacterium tuberculosis is another human host who has either an active or a latent state of tuberculosis presently in his or her body. The infected person coughs, sneezes, or otherwise expels moisture into the environment or onto another person’s body. The new host will inhale the same air in the newly infected environment and the bacteria are then transported into the respiratory tract, such as the lungs (Brighenti & Lerm, 2012). Once inside the respiratory tract, the bacteria are identified as foreign or infectious bodies and are engulfed by macrophages - cells designed to kill foreign bodies (Brighenti & Lerm, 2012). When engulfed, the Mycobacterium tuberculosis sits, latent (dormant) and protected in its resilient cellular structure. When the immune system of the host is weakened and the macrophages die or must do work elsewhere in the body, the Mycobacterium tuberculosis is released and becomes active (Brighenti & Lerm, 2012).

While the Mycobacterium tuberculosis is lying dormant or, in other words, controlled by the host’s immune system, the diversity of the pathogenic bacterium means it can travel around the host body, establishing clusters of the bacterium in various areas of the body (Laal, 2012). In a study published in 2012, researchers found that subjects who were infected with tuberculosis had latent Mycobacterium tuberculosis in the liver, spleen, and kidneys. The participants in this study were all infected with different strains of Mycobacterium tuberculosis, indicating that the ability to spread and establish cells throughout the body is a characteristic of all forms of tuberculosis (Laal, 2012). This ability to spread throughout the body while still evoking no outward symptoms of the disease of the host is what allows Mycobacterium tuberculosis to spread rampantly throughout the human population (Laal, 2012). When an individual shows symptoms of illness, it is typical behavior to treat the symptoms and/or the underlying illness. However, because tuberculosis can be latent and not display symptoms, it goes untreated and easily spread by common human behaviors such as coughing and sneezing.

Active tuberculosis infection is characterized by cough, fever, chest pain, and, eventually, bloody expectorations (Brighenti & Lerm, 2012). While researchers are still exploring what behaviors Mycobacterium tuberculosis undergoes inside the body to cause these symptoms, there is a standing theory that researchers are working to prove (Laal, 2012). The theory states that Mycobacterium tuberculosis replicates in the cells of the inner tissues of the host's lungs using a protein referred to as ESAT6 (Laal, 2012). ESAT6 forms pores that cause cytolysis, the bursting of cells due to osmotic imbalance (Laal, 2012). Using this protein, the bacterium destroys healthy cells and anchor onto the surfaces of lung cells, causing damage to the cells all the way through to the basement membrane of the organ. The host then suffers from severe and widespread damage to the cells forming the inner walls of the lungs and coughs up bloody expectorations (Laal, 2012).

Medical professionals and patients have a strong force to fight against when battling tuberculosis. Over the centuries, tuberculosis has evolved as a disease. At present, there are numerous strands of the infection that all behave differently in the treatment process. Some strands have even become resistant to several types of drugs. The number of multidrug-resistant strains of Mycobacterium tuberculosis is rising, as is the number of cases of tuberculosis involving a multi-drug resistant strain (Hingley-Wilson et al., 2013). In a four-year study, researchers evaluated the prevalence rate of multidrug-resistant tuberculosis in India (Maurya et al., 2013). Over the course of four years, the prevalence of multidrug-resistant tuberculosis rose from 36.4% of existing tuberculosis cases in 2007 to 40.8% of cases in 2010 (Maurya et al., 2013). Researchers also found that the prevalence of multidrug-resistant tuberculosis was even greater in new cases, with rates at 29.1% in 2007 and 43.3% in 2010. The majority of the cases of multidrug-resistant tuberculosis strains were found to be pulmonary as opposed to extrapulmonary (Maurya et al., 2013).

The prevalence of multidrug-resistant tuberculosis "is generally assumed to result from in vivo evolution of drug resistance caused by poor therapy compliance or, in high-incidence settings, from exogenous reinfection with a multidrug-resistant strain" (Hingley-Wilson et al., 2013). This means that for patients who are prescribed a drug regimen and fail to comply with their doctor's orders, they are putting themselves at risk for creating a drug-resistant strain of tuberculosis within their bodies. Another cause for concern is when a client successfully heals from tuberculosis but is then reinfected with a stronger multidrug-resistant strain of tuberculosis.

While these two forms of essentially creating a multidrug-resistant strain of tuberculosis are well known among practicing medical professionals, researchers Hingley-Wilson and colleagues believe they have found an additional method by which tuberculosis bacteria have evolved to become resistant to medications (Hingley-Wilson et al., 2013). Researchers now believe that it is possible that patients are being co-infected (infected by two strains simultaneously) by a drug-sensitive strain and a so-far undetected drug-resistant strain. When the drug-sensitive strain is detected by doctors, the patient is treated with the necessary medications (Hingley-Wilson et al., 2013). While the drug-sensitive strain of tuberculosis is killed off, the undetected drug-resistant strain adapts to the new drug and becomes resistant to it, too; therefore becoming multidrug-resistant (Hingley-Wilson et al., 2013).

In order to test this theory, researchers collected two Mycobacterium tuberculosis strains from a 68-year-old man in Portugal who, other than tuberculosis, had no other health problems. They isolated these strains from one another to grow cultures with which to conduct the study in larger quantities (Hingley-Wilson et al., 2013). The researchers then imitated the theory in vitro and found that the treatment of the drug-sensitive strain did, in fact, cause a drug-resistant strain to emerge. This study shows "the urgent need for improved diagnostic techniques that can properly identify mixed populations of tubercle bacilli" (Hingley-Wilson et al., 2013). By jumping ahead to the treatment phase without first identifying the strains of bacteria present in a patient, medical professionals may be unknowingly creating more resistant strains of tuberculosis, which could lead to an epidemic.

The threat of multidrug-resistant tuberculosis is very real and very high. In 2005, molecular epidemiologists from the University of Stellenbosch found a new break out of a particularly drug-resistant strain of tuberculosis in South Africa (Schmidt, 2008). The strain they found, referred to as Beijing 220, originated thousands of miles away from where the researchers encountered it in 2005. Beijing 220 was beginning to show up in clusters all over the world (Schmidt, 2008). Researchers stated that Beijing 220 "competes successfully for survival with drug-susceptible strains and, under certain circumstances, it can morph easily into 'extensively drug-resistant tuberculosis'… the most terrifying form of the illness, resistant to virtually all known treatments" (Schmidt, 2008). While this infectious bacterium is evolving, medical professionals are desperately trying to reach, identify, and help those suffering from tuberculosis.

In a country suffering widely from numerous illnesses in addition to tuberculosis infections, health care in general and appropriate treatments are difficult to provide due to complications of dual- or multiple-diagnoses. For example, “tuberculosis is the leading opportunistic infection among people living with HIV, and HIV is the strongest risk factor for developing TB disease” (Daftary, 2012). According to Daftary (2012), 12% of more than 9 million new tuberculosis cases worldwide were HIV-positive in 2009, equally approximately 1.1 million people. This example of dual-diagnosis greatly complicates the process of providing treatment for tuberculosis to patients.

In addition to the prevalence of dual- and multiple-diagnoses amongst tuberculosis patients, health care and treatment providers in India also struggle with poverty levels of patients and specific districts (Kamineni et al., 2012). In India, 41.8% of the population is living below the international poverty line as established by the World Bank. The issues of poverty and tuberculosis are united under the fact that “deprivation of health is the second most significant contributor to overall poverty in India” (Kamineni et al., 2012). The poor are less likely to seek out health care for fear of having medical bills to pay or simply being turned away due to inability to pay. This results in non-treatment which, in turn, causes the further spread of the illness amongst poor communities. According to Kamineni and colleagues, the “socio-economic determinants such as poverty, overcrowding, food insecurity and malnutrition… are also responsible for inequities in accessing TB care” (Kamineni et al., 2012). The cycle of poverty leading to disease and disease leading to poverty is a tragic cycle that is difficult to interrupt. Researchers have found that the “poor were two times more likely to have TB, three times less likely to access TB care, four times less likely to complete treatment and many times more likely to incur impoverishing payments for TB care” (Kamineni et al., 2012).

Because treatments for tuberculosis have, historically, caused debt, loss of income from inability to work, stigmatization and homelessness, individuals suffering from tuberculosis or suffering from symptoms that they suspect may be caused by tuberculosis are less likely to seek treatment (Kamineni et al., 2012). While the incidence of tuberculosis is declining (Kamineni et al., 2012; Kolappan et al., 2013), India is still the leading nation in tuberculosis cases and more must be done to assist the nation in healing the affected population. Currently, there are free diagnostic and treatment services available to poor communities provided by the Revised National Tuberculosis Control Programme (RNTCP), however, they are not being used by those in need (Kamineni et al., 2012). Research surveys have shown that many patients suffering from tuberculosis are illiterate and perhaps have not been able to process the information regarding the free services (Kamineni et al., 2012). Instead, they are going to doctors outside of the DOTS-based RNTCP and paying their own expenses or not seeking treatment at all (Kamineni et al., 2012). At present, the DOTS-based RNTCP personnel are making efforts via marketing strategies to make the services provided by the program better known to the poorer communities, specifically, in the hopes that people will take advantage of the free resources available to them (Kamineni et al., 2012). Ideally, this tactic will help both the poverty issue and the widespread problem of tuberculosis.

In another study, researchers aimed to determine reasons why people suffering from tuberculosis were not seeking treatment, even though it was found that the earlier an infected patient begins treatment, the greater likelihood for success of a treatment program (Grover et al., 2014). Curious to find out what treatment pathways patients were using and how they made their decisions, researchers conducted a cross-sectional study of patients in a chest clinic of a tertiary care hospital (Grover et al., 2014). The researchers found several factors involved in the reason why patients delayed seeking treatment, including not knowing where the nearest health facility was or being unsure of what services the health centers offered and how much they charged (Grover et al., 2014). Those who took less time in seeking out treatment complained of serious fever, joint pain, skin lesions and nodular skin swelling (Grover et al., 2014). Interestingly, patients with lower levels of education, lower-status occupations, and a perception that their symptoms were not serious often delayed their treatment for more than three and a half weeks after noticing symptoms (Grover et al., 2014). This study indicates that to the people of India, being able to pay one’s bills is a higher priority than getting treatment for chronic illness; indicating pride as a cultural staple. Researchers concluded that it is absolutely essential to increase public awareness and educate through cultural health promotion regarding the seriousness of tuberculosis, and the availability of facilities in order to prevent such long delays in seeking treatment (Grover et al., 2014). This need for increased awareness is a conclusion that has been reached by many who have evaluated the socioeconomic structure of India as it pertains to treatment for tuberculosis (Thakur & Murhekar, 2012).

India is doing well to care for tuberculosis patients to the best of its ability. However, it is important to keep in mind that there are national guidelines that must be adhered to in order to provide adequate care. In a study by Kondapaka et al. (2012), researchers assessed whether or not patients at a tertiary care hospital in Hyderabad, India were being treated according to national guidelines. In their study, researchers observed a total of 3,120 patients who were admitted to the hospital (Kondapaka et al., 2012). Of these admitted patients, 1,218 (39%) required treatment for tuberculosis (Kondapaka et al., 2012). Of the tuberculosis patients, 98% were treated according to national guidelines (Kondapaka et al., 2012). The remaining 2% (28 patients) were treated in ways not in accordance with the national guidelines (Kondapaka et al., 2012). These 28 patients who were not treated according to guidelines were instead treated with multidrug-resistant tuberculosis treatment regimens or adhoc regiments (Kondapaka et al., 2012). While the health care providers did deviate from the nationally approved guidelines for treating tuberculosis, the deviations were justified and were in the best interest of the patient. With regard to multidrug-resistant strains of tuberculosis, the national guidelines are not yet specific enough to provide direction for such cases. Therefore updates ought to be made to the national guidelines in everyone's best interest.

Even amongst such a great health threat in India, researchers and medical professionals alike are extremely concerned with the quality of life of people suffering from tuberculosis. In a study by Aggarwal et al. (2013), researchers conducted a total of 2,654 health-related quality of life assessments for newly diagnosed pulmonary tuberculosis patients. In the entire study, 1,034 patients were assessed (Aggarwal et al., 2013). The researchers assessed the patients at the beginning of the intensive phase of their treatment programs and again at the completion of the treatment program (Aggarwal et al., 2013). The assessments scored for four categories of quality of life including physical, psychological, social relationships, and environmental factors (Aggarwal et al., 2013). The researchers found that men typically reported a higher quality of life than did women (Aggarwal et al., 2013). Other groups that scored higher on quality of life were urban residents (compared with rural residents), younger patients, patients with higher socioeconomic status, and those with less severe forms of the disease (Aggarwal et al., 2013). The researchers concluded that patients with tuberculosis have a low quality of life, but the quality of life "improves rapidly and significantly" when patients are in a treatment program (Aggarwal et al., 2013). This research study shows that treatments are helping patients enjoy more comfortable lives than if they were not to get treatment at all. This research study also has long-term applications in that health care providers can use the tools used by these researchers to evaluate the quality of life their patients are experiencing and make necessary changes if low scores are reported.  

Works Cited

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