The Global Impact and Persistent Challenges of Tuberculosis Today

Tuberculosis remains a leading infectious killer worldwide, facing complex challenges from drug resistance to equitable access to care.

By Garret Merkley · Explainer · Jun 21, 2026

Branched from The History of Tuberculosis Treatment and the Dawn of Antibiotics

Quick take

Tuberculosis (TB) is still one of the world's deadliest infectious diseases, second only to COVID-19.
Key challenges include drug-resistant strains, underdiagnosis, and unequal access to effective treatment.
Poverty, malnutrition, and HIV co-infection significantly worsen the TB epidemic, especially in vulnerable populations.
While progress is being made with new tools, sustained global funding and political commitment are essential to end TB.

Tuberculosis (TB) is a serious infectious disease caused by the bacterium *Mycobacterium tuberculosis*. While primarily affecting the lungs, it can attack any part of the body, including the spine, brain, and kidneys. Though preventable and curable, TB remains a major global health crisis, responsible for millions of illnesses and deaths each year.

The Global Burden of Tuberculosis

Despite significant progress over the decades, TB continues to be one of the world’s deadliest infectious diseases. It is estimated that a quarter of the world's population has latent TB infection, meaning they carry the bacteria but do not have active disease or symptoms. However, 5-10% of these individuals will develop active TB disease in their lifetime. The disease disproportionately affects low- and middle-income countries, with the majority of cases and deaths occurring in Southeast Asia, Africa, and the Western Pacific regions. Factors like poverty, malnutrition, crowded living conditions, and co-infection with HIV fuel its spread.

Persistent Challenges in TB Control

Efforts to eradicate TB face several formidable obstacles:

**Drug-Resistant TB:** One of the most critical threats is the rise of drug-resistant strains. Multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) emerge when patients do not complete their full course of treatment, or when healthcare providers prescribe the wrong drugs. These forms of TB are much harder and more expensive to treat, requiring longer regimens with more toxic drugs, and have lower cure rates.
**Diagnosis Gaps:** Millions of people with active TB are never diagnosed or are diagnosed too late, allowing the disease to spread further. Diagnostic tools, especially in resource-limited settings, can be slow, complex, or miss cases, particularly in children or people with HIV.
**Access to Treatment and Care:** Even when diagnosed, many patients struggle to access or complete the long, complex treatment regimens. Issues include the cost of drugs, lack of access to healthcare facilities, inadequate patient support, and social stigma.
**HIV Co-infection:** People living with HIV are much more likely to develop active TB if infected with the TB bacteria, and the co-infection makes both diseases harder to treat. TB is a leading cause of death among people living with HIV.
**Research and Development:** While new drugs, vaccines, and diagnostics are emerging, investment in research and development for TB has historically lagged behind other major diseases.

Why Ending TB Matters Today

Ending the TB epidemic is not just a health goal; it's crucial for global development and equity. TB disproportionately affects the most vulnerable populations, trapping individuals and families in cycles of poverty. It places a huge burden on healthcare systems and national economies, hindering productivity and development. Achieving the Sustainable Development Goals (SDGs), particularly those related to health, poverty, and inequality, hinges on successfully tackling TB. Global efforts, including sustained funding, political commitment, and innovative strategies, are vital to reach the goal of eradicating this ancient, yet persistent, disease.

Is TB still common in developed countries?

While less common than in high-burden countries, TB still occurs in developed nations, often among immigrant populations from endemic areas, people experiencing homelessness, or those with weakened immune systems. Drug-resistant forms are also a concern globally.

How is TB spread?

TB is spread through the air when people with active lung TB cough, sneeze, or speak, expelling tiny droplets containing the bacteria. Others can become infected by inhaling these droplets.

What is the difference between latent TB and active TB?

In latent TB, the bacteria are present in the body but are inactive, causing no symptoms and not contagious. In active TB, the bacteria are multiplying, causing symptoms like persistent cough, fever, night sweats, and weight loss, and the person can spread the disease to others.

Can TB be prevented?

Yes. The BCG vaccine can protect children from severe forms of TB, though its effectiveness against adult pulmonary TB varies. Preventive treatment (isoniazid, rifapentine, or rifampicin) can be given to people with latent TB infection to prevent them from developing active disease. Good ventilation, early diagnosis, and complete treatment of active cases are also key to prevention.

How long does TB treatment take?

Treatment for drug-susceptible TB usually involves a combination of antibiotics taken for at least 6 months. Drug-resistant forms of TB require much longer and more complex regimens, sometimes lasting 18-24 months or more, with different, often more toxic, medications.

Sources

World Health Organization (WHO) Global TB Report
Centers for Disease Control and Prevention (CDC) - Tuberculosis (TB)