Tuberculosis

Key Facts about Tuberculosis (TB)

- Mortality and Prevalence: In 2022, TB claimed the lives of 1.3 million people, including 167,000 with HIV. TB ranks as the second deadliest infectious disease worldwide, following COVID-19.

- Incidence: An estimated 10.6 million people contracted TB globally in 2022, with 5.8 million men, 3.5 million women, and 1.3 million children affected. TB affects all nations and age groups, but it is both preventable and curable.

- Drug Resistance: Multidrug-resistant TB (MDR-TB) is a significant public health issue, with only 40% of those affected receiving treatment in 2022.

- Global Impact: Efforts to combat TB have saved approximately 75 million lives since 2000. Achieving the global targets set at the 2018 UN high-level meeting on TB requires an annual investment of $13 billion.

- Sustainable Development Goals (SDGs): Eradicating TB by 2030 is a health target within the United Nations SDGs.

Overview of Tuberculosis

TB primarily impacts the lungs and is transmitted through the air via coughing, sneezing, or spitting by infected individuals. Approximately one-quarter of the world's population is infected with TB bacteria, with 5-10% likely to develop the disease. Those with latent TB are not contagious. The disease is treatable with antibiotics, but without treatment, it can be fatal. The Bacille Calmette-Guérin (BCG) vaccine, administered in some countries to children, prevents severe forms of TB outside the lungs.

Symptoms

People with latent TB do not exhibit symptoms and are not contagious. Those who develop TB disease may experience prolonged coughing (sometimes with blood), chest pain, weakness, fatigue, weight loss, fever, and night sweats. Symptoms vary depending on the affected part of the body, which can include the lungs, kidneys, brain, spine, and skin. Higher risk factors for TB disease include diabetes, weakened immune systems (e.g., HIV/AIDS), malnutrition, and tobacco use.

Prevention

To prevent TB infection and spread:

- Seek medical help if experiencing symptoms like prolonged cough, fever, or unexplained weight loss.

- Get tested if at increased risk, such as having HIV or close contact with TB patients.

- Complete prescribed preventive treatment courses.

- Practice good hygiene if infected, including wearing masks and properly disposing of tissues.

 Diagnosis

The WHO recommends rapid molecular diagnostic tests, like the Xpert MTB/RIF Ultra and Truenat assays, for initial TB diagnosis. These tests offer high accuracy and aid in early detection. The tuberculin skin test (TST) or interferon-gamma release assay (IGRA) can identify TB infection. Diagnosing drug-resistant TB and HIV-associated TB can be complex and costly, particularly in children.

 Treatment

TB is treated with antibiotics, typically isoniazid, rifampin, pyrazinamide, ethambutol, and streptomycin, taken daily for 4-6 months. Incomplete treatment can lead to drug resistance. Multidrug-resistant TB (MDR-TB) requires extensive, often toxic, second-line treatments. New WHO guidelines recommend a 6-month regimen for MDR-TB to reduce treatment burden and costs.

 TB and HIV

HIV significantly increases the risk of developing TB, with people living with HIV being 16 times more likely to contract TB. TB is a leading cause of death among people with HIV. Effective treatment is crucial, as HIV and TB together exacerbate each other’s effects. Collaborative TB-HIV activities are essential to reduce mortality.

 Impact

TB primarily affects adults in their productive years but can impact all age groups, especially in low- and middle-income countries. The highest incidence rates are in the WHO South-East Asian, African, and Western Pacific regions. TB poses significant financial burdens, with about half of TB patients facing catastrophic costs. Risk factors for TB include undernutrition, HIV, alcohol use disorders, smoking, and diabetes. In 2022, undernutrition, HIV, alcohol use, smoking, and diabetes were major contributors to new TB cases.