Tuberculosis: Why Does It Remain a Global Health Concern?
Introduction
Tuberculosis (TB) is among the oldest and most lethal infectious diseases in human history. Despite significant advancements in medical science and the development of effective treatments, TB continues to be a global health threat, claiming millions of lives every year. According to the World Health Organization (WHO), TB remains one of the top 10 causes of death worldwide, with nearly 10 million people falling ill with TB annually. The disease poses complex challenges to healthcare systems, making it crucial to understand why tuberculosis remains such a persistent global health concern.
What is Water Contamination?
Tuberculosis is a communicable disease caused by the Mycobacterium tuberculosis bacterium and is transmitted through the air when an infected individual coughs, sneezes, or talks. While it mainly targets the lungs, it can also affect other body areas, such as the kidneys, spine, and brain. The bacteria can remain airborne for a long time, making it easy for individuals in close proximity to become infected.
Symptoms of TB include chronic cough, weight loss, fatigue, fever, and night sweats. If left untreated, TB can lead to serious complications or even death. Fortunately, TB is curable with a course of antibiotics, but incomplete or improper treatment can lead to drug resistance.
Global Impact of Tuberculosis
Despite the availability of effective treatment, TB continues to be a global health challenge. In 2021, the World Health Organization (WHO) reported 10.6 million new cases of TB and 1.6 million deaths worldwide. Additionally, around 1.7 billion people are estimated to be latently infected with TB, meaning they carry the bacteria but do not show symptoms. These individuals are at risk of developing active TB if their immune system weakens. TB remains the 13th leading cause of death globally, and it is the second leading infectious killer after COVID-19.
While TB can affect anyone, regardless of location or socioeconomic status, it is especially prevalent in low- and middle-income countries. These nations bear the lion’s share of the global TB burden, with around 80% of all new TB cases occurring in these regions. In fact, TB is the eighth and seventh leading cause of death in low- and middle-income countries, respectively. The disease also places a significant burden on these nations’ healthcare systems, hindering economic development and straining resources
Eight countries accounted for two-thirds of the global total of tuberculosis (TB) cases. These countries include:
- India
- China
- Indonesia
- Philippines
- Pakistan
- Nigeria
- Bangladesh
- South Africa.
Together, they represent the highest burden of TB globally, underlining the need for focused interventions and enhanced healthcare systems in these regions to combat the ongoing TB crisis.
Why Does Tuberculosis Remain a Global Health Concern?
While TB is preventable and treatable, several factors contribute to its ongoing prevalence worldwide.
1. Inadequate Diagnosis
In many parts of the world, TB remains underdiagnosed, particularly in resource-poor settings. There is often a lack of healthcare infrastructure and limited access to diagnostic tools such as chest X-rays and sputum tests. Many people with TB go undiagnosed or misdiagnosed, which leads to delays in treatment and the continued spread of the disease.
2. Delayed or Incomplete Treatment
One of the most significant barriers to controlling TB is the delayed initiation of treatment and non-compliance with the prescribed regimen. TB treatment requires a lengthy course of multiple antibiotics—typically six to nine months. Patients who fail to complete the treatment as prescribed are at risk of developing drug resistance, which complicates future treatment efforts.
3. Drug Resistance
One of the most pressing issues in the fight against tuberculosis is the rise of drug-resistant TB. This form of TB occurs when the bacteria become resistant to one or more of the drugs used to treat it. The overuse and misuse of antibiotics, especially in low- and middle-income countries, have contributed to the development of drug-resistant TB. Multidrug-resistant TB (MDR-TB) is resistant to at least two of the most commonly used drugs—isoniazid and rifampicin—while extensively drug-resistant TB (XDR-TB) is resistant to even more drugs.
The emergence of drug-resistant TB makes treatment pricier and lengthier, placing an enormous burden on already strained healthcare systems. Patients with drug-resistant TB may require treatment for up to two years, and the drugs used are often less effective and come with severe side effects.
4. Malnutrition
Tuberculosis disproportionately affects those living in poverty due to poor living conditions, overcrowding, and limited access to healthcare. People living in poverty may also have limited access to proper medical care and may delay seeking treatment due to the cost of healthcare. Malnutrition weakens the immune system, making individuals more susceptible to contracting TB. In many low-income countries, the intersection of poverty and poor nutrition creates a perfect storm for the spread of tuberculosis.
5. Globalization and Increased Mobility
As the world becomes increasingly interconnected through travel and migration, the spread of TB has become a more significant concern. People frequently move between countries with high TB burden and those with lower rates of the disease. This migration can inadvertently introduce new strains of TB into countries with lower incidence, making it more difficult to control its spread.
In particular, individuals living in crowded conditions, such as refugee camps, prisons, or slums, are at a higher risk of contracting TB. These environments provide the perfect conditions for the bacteria to spread rapidly. Additionally, global mobility means that individuals with undiagnosed TB can travel long distances before receiving proper care, allowing the disease to spread across borders.
6. HIV Co-Infection
The HIV/AIDS epidemic has compounded the challenge of controlling TB. HIV weakens the immune system, making individuals much more susceptible to developing active TB if they are exposed to Mycobacterium tuberculosis. In fact, people living with HIV are 15-22 times more likely to develop TB than those without HIV.
Coinfection of TB and HIV is a significant problem in sub-Saharan Africa and other regions where both diseases are prevalent. In these regions, TB remains the leading cause of death among people living with HIV. The coexistence of TB and HIV complicates treatment, as both conditions require specialized care and drugs that can interact with each other.
7. Diabetes and Other Comorbidities
Certain conditions, such as diabetes, increase the risk of developing TB. Diabetes weakens the immune system and impairs the body’s ability to fight off infections, making individuals with uncontrolled blood sugar more susceptible to TB. Diabetes also complicates the management of TB, as the drugs used to treat TB may interact with medications for diabetes, requiring careful monitoring and adjustments in treatment. People with diabetes have a higher risk of developing active TB if they are exposed to the bacteria, particularly in regions where both diseases are prevalent.
COVID-19 Pandemic and Its Impact on TB Control
Since the end of 2019, the COVID-19 pandemic has had a severe impact on global healthcare systems, diverting resources and attention from TB control programs. The pandemic led to widespread reductions in healthcare services, as hospitals and clinics were overwhelmed with COVID-19 cases, and resources were reallocated to combat the new virus. This disruption has had direct consequences for TB diagnosis, treatment, and prevention efforts.
By the end of 2020, the pandemic had caused a 20% decrease in TB detection and treatment. This reduction was primarily due to the reallocation of healthcare facilities and personnel, which left fewer resources available for TB care. Moreover, there was an 18% drop in case notifications, meaning that many people with TB went undiagnosed or untreated, leading to an increase in undetected and untreated cases globally.
The interruption in TB services also led to an alarming rise in TB deaths. For the first time since the early 2000s, the number of TB-related deaths increased in 2020, reversing years of progress in reducing mortality. This setback underscores the profound impact that the COVID-19 pandemic has had on the global effort to control TB and highlights the interconnectedness of healthcare systems when addressing multiple public health threats simultaneously.
Strategies to End Tuberculosis
To combat the growing challenge of TB, the World Health Organization (WHO) introduced the End TB Strategy in 2014, a comprehensive approach designed to reduce the global TB burden significantly by 2030. The strategy aligns with the United Nations’ Sustainable Development Goals (SDGs) and was endorsed during the high-level meeting at the UN General Assembly in 2018. The ultimate goal is to eliminate TB as a public health threat, ensuring equitable access to quality diagnosis, treatment, and care for all affected individuals.
Core Pillars of the End TB Strategy
The End TB Strategy is structured around three main pillars designed to accelerate the global response to tuberculosis:
- Integrated, Patient-Centered Care and Prevention: This pillar focuses on providing high-quality diagnosis, treatment, care, and prevention services tailored to the needs of the patient. The aim is to ensure that care is accessible, effective, and delivered in a patient-friendly manner.
- Bold Policies and Supportive Systems: This involves implementing supportive policies that enable the effective delivery of TB services. It also encourages governments to ensure health systems are strengthened to support TB care, including removing financial and social barriers to treatment.
- Intensified Research and Innovation: Innovations in diagnostics, treatment, and vaccines are central to the strategy. The goal is to develop faster, more accurate diagnostic tests, more effective drugs, and preventive vaccines to combat TB.
Progress and Challenges in Achieving the Targets
While the End TB Strategy has set ambitious milestones to track progress, these targets have been challenging to meet. Some key achievements and setbacks include:
Declining Incidence
Since 2015, the global incidence of TB has been decreasing at an annual rate of 2%. However, by 2020, the overall reduction was only 11%, falling short of the intended 20% target. This gap has been exacerbated by the COVID-19 pandemic, which disrupted TB diagnosis, treatment, and reporting systems. As a result, only 5.8 million of the 9.9 million estimated cases were reported and treated in 2020, leaving a significant gap of 4.1 million missing TB cases.
Increased Mortality
Mortality rates rose by 5.6% in 2020 compared to 2019, reversing some of the progress made in previous years. The overall reduction in TB-related mortality was 9.2%, falling well short of the 35% reduction target by 2020.
HIV and TB Co-Infection
Despite the setbacks, one area where progress has been made is in the prevention and treatment of TB among people living with HIV. The number of people receiving TB preventive treatment has increased, aligning with the goals set by the End TB Strategy.
Conclusion
Tuberculosis remains a formidable global health challenge, exacerbated by factors such as inadequate healthcare systems, poverty, malnutrition, HIV co-infection, and the rise of drug-resistant strains. While progress has been made in the fight against TB, much work remains to be done to eliminate this disease. A comprehensive, global response that combines early diagnosis, effective treatment, and social reforms is essential for reducing the burden of tuberculosis worldwide. Until then, TB will continue to be a health crisis that requires the attention and cooperation of governments, healthcare providers, and the global community.
