Tuberculosis (TB) remains one of the most pressing public health challenges in India, which bears the highest global burden of the disease. Vulnerable populations, including migrants, prisoners, and indigenous communities, face unique challenges in accessing TB care, exacerbating the risk of transmission and increasing the prevalence of multidrug-resistant TB (MDR-TB). ^1-3

This review focuses on the specific challenges faced by these groups, explores the barriers to healthcare access, and highlights successful interventions and initiatives that aim to reduce TB transmission and improve treatment outcomes.

1. TB Among Migrants^[4-6]

1.1 The Migrant Crisis and TB Vulnerability

India's large internal migrant population, estimated to exceed 100 million, is a critical factor in the country's TB burden. Migrants often travel from rural to urban areas in search of better job opportunities but frequently live in densely populated, unsanitary conditions that facilitate the spread of airborne diseases like TB. Overcrowding, poor ventilation, and lack of access to healthcare contribute to their increased susceptibility. Migrant laborers, particularly those working in construction, brick kilns, and other low-wage sectors, are particularly vulnerable, as their transient lifestyles impede access to healthcare, continuity of care, and adherence to long-term treatment regimens.

1.2 Barriers to Care for Migrants

Several barriers impede migrants' ability to access TB care. One primary barrier is the informal nature of their employment, which often comes without health benefits, discouraging workers from taking time off to seek medical help. Many migrants fear losing wages or their jobs if they disclose illness. Additionally, they often lack the necessary documentation, such as government-issued identity cards, which further prevents access to public healthcare services. Another significant barrier is stigma, which deters individuals from seeking help, fearing ostracization from employers and co-workers.

Migrants frequently move across states in search of work, leading to challenges in maintaining treatment adherence, as long TB treatment regimens require regular follow-up over several months. The mobility of migrants makes it difficult for healthcare providers to ensure continuous monitoring and adherence to treatment, increasing the risk of developing drug-resistant TB.

1.3 Successes and Initiatives for Migrants

Recognizing the challenges faced by migrant populations, the National Tuberculosis Elimination Program (NTEP) has launched several migrant-focused interventions. Mobile health units have been deployed to screen and treat TB in high-density migrant workplaces, such as construction sites, brick kilns, and factories. These mobile units provide on-the-spot testing and care, reducing the need for migrants to travel to distant healthcare centers.

For example, in Maharashtra, mobile clinics and outreach teams have helped identify previously undiagnosed TB cases among migrant workers, facilitating early treatment initiation. Additionally, the introduction of the Nikshay system has revolutionized TB care for mobile populations. Nikshay is a digital platform that enables the tracking of TB patients across state lines, ensuring that migrants receive consistent treatment, even when they move for work.

Moreover, state governments have partnered with NGOs to conduct TB awareness campaigns aimed at reducing stigma and educating migrant workers about the importance of seeking timely care and adhering to treatment regimens.

2. TB in Prison Populations^[7-11]

2.1 Overcrowding and Health Vulnerabilities in Prisons

India’s prisons are severely overcrowded, with many facilities operating at more than twice their capacity. This overcrowding, coupled with poor ventilation and inadequate sanitation, creates an environment highly conducive to the spread of infectious diseases, particularly TB. Studies have shown that the TB prevalence rate in prisons is significantly higher than in the general population. The confined nature of prison spaces, combined with poor nutrition and the prevalence of underlying health conditions such as substance abuse and mental illness, further exacerbates the risk of TB transmission.

2.2 Challenges to TB Control in Prisons

A major challenge in controlling TB in prisons is the lack of adequate screening mechanisms. Many prisoners enter the correctional system with undiagnosed TB, and in the absence of systematic screening, they may unknowingly transmit the disease to other inmates. Moreover, prison healthcare services are often under-resourced, with limited access to diagnostic tools such as GeneXpert, which are essential for diagnosing TB and MDR-TB.

Another significant challenge is ensuring treatment adherence within the prison system. Inmates who are released or transferred before completing their TB treatment are at risk of interrupting therapy, leading to incomplete treatment and increasing the likelihood of drug-resistant TB strains emerging.

2.3 TB Control Measures in Prisons

To address the high TB burden in prisons, several state governments have launched prison-specific TB control programs. For instance, in Tamil Nadu, prison authorities have collaborated with the NTEP to implement regular TB screenings for incoming inmates, as well as improved ventilation in cells to minimize transmission. The introduction of mobile diagnostic units in prisons has also been an effective strategy, enabling on-site testing and immediate treatment initiation.

Moreover, the Directly Observed Treatment, Short-course (DOTS) strategy has been widely adopted in prisons, ensuring that inmates diagnosed with TB are closely monitored to complete their treatment. In some facilities, telemedicine platforms have been introduced, allowing prison healthcare staff to consult with TB specialists and access expert advice, further improving the quality of care available to inmates.

3. TB in Indigenous Communities^[12-15]

3.1 Health Disparities Among Indigenous Populations

India's indigenous communities, referred to as Scheduled Tribes (STs), are particularly vulnerable to TB due to extreme poverty, malnutrition, and limited access to healthcare. These communities, often located in remote and underserved areas, experience disproportionately high rates of TB compared to the general population. Factors such as geographic isolation, poor healthcare infrastructure, and widespread malnutrition exacerbate the problem, making it difficult for indigenous populations to access timely diagnosis and treatment.

3.2 Cultural and Socioeconomic Barriers to TB Care

Indigenous populations face not only geographic and economic challenges but also cultural barriers that hinder access to TB care. Traditional healers, who play a prominent role in indigenous healthcare, may discourage patients from seeking formal medical treatment, leading to delays in diagnosis and treatment initiation. Additionally, indigenous communities have historically been marginalized, fostering distrust in government-led healthcare initiatives, which further hinders their willingness to engage with public health systems.

Socioeconomic factors, including high rates of malnutrition, weaken immunity and increase susceptibility to TB. Furthermore, many indigenous people lack education about TB transmission and treatment, leading to low adherence rates and high levels of stigma surrounding the disease.

3.3 Interventions Targeting Indigenous Populations

To address the unique challenges faced by indigenous communities, several community-based initiatives have been implemented. In Odisha, for example, the government has trained community health workers (CHWs) from within indigenous populations to recognize TB symptoms and provide treatment using the DOTS model. This community-based approach has been effective in increasing treatment adherence and reducing TB-related stigma.

Mobile diagnostic units, equipped with GeneXpert machines, have been deployed to remote indigenous regions, allowing for the rapid diagnosis of TB and MDR-TB. These units bring healthcare services directly to the doorstep of indigenous communities, reducing the need for long and costly journeys to distant healthcare facilities.

NGOs have also played a crucial role in bridging the healthcare gap for indigenous populations. In collaboration with government agencies, NGOs have developed culturally sensitive awareness campaigns that respect indigenous beliefs while promoting modern TB treatment. These efforts have been successful in improving healthcare access and outcomes for indigenous populations across various states, including Odisha and Madhya Pradesh.

4. Challenges in TB Control for Vulnerable Populations^[16-20]

4.1 Stigma and Discrimination

Stigma surrounding TB remains a significant barrier, particularly among vulnerable populations such as migrants, prisoners, and indigenous groups. This stigma is rooted in long-standing misconceptions about the contagiousness and severity of TB, which can lead to fear and discrimination. For migrants, who often live in close-knit communities with shared housing and workspaces, being diagnosed with TB can result in social ostracism. Migrants, particularly those in lower-income or informal sectors, often fear losing employment or being sent back to their home regions if their TB status is disclosed, leading to delayed diagnosis and treatment.

In prison settings, stigma can also prevent inmates from reporting symptoms, as they may fear further marginalization within an already isolated environment. Prisoners diagnosed with TB may face increased isolation, which can impact their mental health and reduce their willingness to comply with treatment. Similarly, indigenous communities, where traditional beliefs dominate, may view TB as a sign of personal or familial weakness, further discouraging individuals from seeking timely medical care.

The discrimination faced by these populations exacerbates the problem, as individuals may avoid public health facilities altogether to escape stigmatization. This leads to increased rates of undiagnosed cases and a higher likelihood of transmission within these communities. To combat this, public health campaigns must focus on raising awareness and reducing TB stigma, leveraging community leaders and healthcare workers to convey accurate information and foster a supportive environment for those affected by TB.

Continuity of care is a significant issue for populations such as migrants and prisoners, where constant mobility hinders the completion of treatment. For migrant workers, particularly those in informal sectors like construction and agriculture, frequent relocation to different job sites means they often do not stay in one place long enough to complete the full six-month course of TB treatment. This transient lifestyle increases the likelihood of treatment interruptions, which can lead to relapse, treatment failure, or the development of drug-resistant TB strains.

In prison settings, the problem of interrupted treatment arises when inmates are transferred between facilities or released before completing their TB regimen. The handover of medical records between prisons is often inadequate, and released prisoners may not have access to continued healthcare, resulting in treatment discontinuation. This lack of follow-up care exacerbates TB transmission within both prison and community settings, particularly when undiagnosed cases go untreated.

Solutions such as the Nikshay digital tracking system have been introduced to monitor and ensure continuity of care across different regions and states. Nikshay allows healthcare providers to track a patient’s treatment history even when they move between different jurisdictions. However, improving the system’s reach and integration into both the public and private healthcare sectors is essential to ensure that all patients remain in the care system until they complete their treatment. Migrant-focused interventions, such as providing TB education and treatment services at worksites, have also been effective in ensuring migrants receive the care they need, regardless of their location.

4.3 Inadequate Healthcare Infrastructure

One of the most critical barriers to effective TB control among vulnerable populations is the lack of healthcare infrastructure, particularly in rural and remote regions where many indigenous populations reside. These areas often lack the diagnostic facilities necessary for rapid TB detection, including essential tools like the GeneXpert machine, which can detect TB and drug resistance quickly. Without these diagnostic capabilities, TB cases are often misdiagnosed or identified too late, resulting in more advanced disease and a higher risk of transmission.

Healthcare access is also limited by physical geography in some regions, particularly among indigenous populations living in mountainous or forested areas. For instance, the remoteness of some tribal regions in Himachal Pradesh makes it difficult for residents to access healthcare facilities regularly, leading to delays in diagnosis and treatment. The absence of local TB specialists and insufficient healthcare personnel further exacerbate these issues, leaving these populations underserved and vulnerable to TB outbreaks.

Expanding healthcare infrastructure to these areas is critical. Efforts must focus on equipping rural health centers with diagnostic tools, ensuring that healthcare workers are trained to handle TB cases, and deploying mobile health units to reach remote populations. Additionally, fostering partnerships with local community organizations and NGOs can enhance the reach of healthcare services by bridging the gap between underserved populations and formal healthcare systems.

5. Recommendations and Future Directions^[1,21,22]

5.1 Strengthening Community-Based Healthcare

To effectively control TB in vulnerable populations, community-based healthcare approaches must be strengthened. Community health workers (CHWs), who are often trusted figures within their communities, play a vital role in identifying symptoms, providing education, and facilitating treatment adherence. Training more CHWs, especially from within indigenous and migrant communities, can improve TB detection and ensure continuity of care.

Engaging traditional healers and community leaders in TB awareness campaigns can also be critical to reducing stigma and increasing treatment acceptance. For example, in tribal areas, involving traditional leaders who hold significant influence can help bridge the gap between modern medicine and traditional beliefs. By fostering collaboration between local leaders and healthcare providers, it becomes easier to build trust in medical interventions, ultimately leading to higher treatment uptake.

Mobile health units and telemedicine solutions are essential tools for overcoming geographic and infrastructural barriers in TB care. Mobile health units equipped with diagnostic tools such as GeneXpert machines allow healthcare providers to bring testing directly to vulnerable populations, especially those in remote or underserved areas. These units can also deliver on-site treatment initiation and follow-up care, reducing the need for patients to travel long distances to healthcare centers.

Telemedicine platforms provide a means for remote consultations between local healthcare workers and TB specialists, enabling more accurate diagnosis and management of complicated cases, particularly in prisons or indigenous regions where access to specialists is limited. Telemedicine can also facilitate regular follow-ups, ensuring that patients adhere to their treatment regimens. Expanding the use of these platforms, alongside mobile health initiatives, is a key strategy for improving TB care among vulnerable populations.

5.3 Improving Coordination Between States and Regions

Migrant populations, due to their high mobility, require improved coordination between different healthcare systems to ensure continuity of care. The Nikshay system has already made significant strides in tracking patient treatment records across state lines, but further investment is needed to optimize its effectiveness. Strengthening coordination between state and regional healthcare systems, as well as involving private healthcare providers in the process, can ensure that migrants do not fall through the cracks when they move between locations.

In addition to tracking systems, integrating TB screening and health education into the workplace can help reduce the incidence of TB among migrant workers. Providing routine screenings at construction sites, factories, and agricultural fields can help identify cases early and ensure that workers receive timely care. Employers can also play a role by supporting health initiatives that promote TB awareness and reduce the stigma associated with the disease.

By addressing these structural and social barriers, India can make significant progress in controlling TB among vulnerable populations. The success of these efforts will depend on sustained investment in healthcare infrastructure, innovative use of technology, and community engagement to build trust and reduce stigma. Through these strategies, India can achieve its goal of TB elimination while ensuring that no population is left behind.

In conclusion, controlling tuberculosis (TB) among vulnerable populations in India, such as migrants, prisoners, and indigenous communities, requires a multifaceted approach that addresses both systemic healthcare gaps and the unique social, economic, and cultural challenges these groups face. While significant strides have been made through initiatives like mobile health units, telemedicine, and digital tracking platforms like Nikshay, structural barriers such as stigma, inadequate healthcare infrastructure, and lack of treatment continuity persist. By investing in community-based healthcare models, expanding digital health tools, and fostering greater coordination across regions, India can better ensure that these vulnerable populations receive timely diagnosis, uninterrupted treatment, and support. The success of these efforts is pivotal to achieving the nation’s ambitious goal of TB elimination by 2025, while ensuring equitable healthcare access for all, particularly those historically left behind.

The authors declare that they have no conflict of interest

No funding sources

The study was approved by the Indira Gandhi Medical College, Shimla, Himachal Pradesh.

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