More than 140 years ago, on 24 March 1882, the German physician Robert Koch announced his discovery of the bacterium Mycobacterium tuberculosis, identifying the cause of tuberculosis (TB) and transforming the understanding of infectious diseases (3). Yet more than a century later, the fight against TB is far from over.
Each year, World TB Day raises awareness about the devastating impact of TB and the global efforts to eliminate it. This year’s theme, “Yes! We can end TB!”, highlights the importance of renewed commitment, innovation, and collaboration in tackling the epidemic (4). Despite significant progress in prevention and treatment, TB remains one of the world’s most serious infectious diseases. In 2024 alone, an estimated 10.7 million people developed TB and about 1.23 million people died from the disease (5). Most cases occur in low- and middle-income countries, with 30 high-burden countries accounting for about 87% of all cases globally (5).
This year, we are encouraging everyone to look beyond the bacteria and consider the host’s role, particularly the strength of the immune system and the factors that help or hinder it.
South Africa is among the countries most affected by TB and remains on the global list of high-burden countries for TB, HIV-associated TB, and drug-resistant TB (6). In 2023, an estimated 270,000 South Africans were diagnosed with TB; there were 13,000 cases of drug-resistant TB, and approximately 56,000 people died from the disease (6). Although incidence has declined and treatment coverage has improved in recent years, TB continues to place significant pressure on the healthcare system, with many patients still facing barriers such as stigma and financial costs when accessing care (7). Therefore, understanding the disease itself remains essential in the continued fight against TB.
TB spreads through the air when people with active TB expel bacteria, for example, by coughing, sneezing, or speaking, allowing others to inhale infectious droplets (1). The disease most commonly affects the lungs, known as pulmonary TB, but it can also affect other organs such as the kidneys, brain, or spine (1). Common symptoms of active TB include a prolonged cough, sometimes with blood, chest pain, fever, night sweats, fatigue, and unexplained weight loss (1). Without treatment, TB can be deadly, with death rates reaching close to 50% in untreated cases (5). Importantly, however, TB is both preventable and curable, with 90% of people diagnosed with TB successfully overcoming the disease (5).
However, infection does not automatically mean disease. In most people, the immune system can control the bacteria and prevent illness. This condition is known as latent TB infection. People with latent TB do not feel sick and cannot spread the disease to others (1). Only a small proportion (5–10%) of infected individuals develop active TB (1). When the immune system is weakened or compromised, the bacteria can begin to multiply, leading to disease and symptoms. This highlights an important aspect of TB: the risk of developing TB is determined not only by exposure to the bacterium, but also by the strength and resilience of the host’s immune system.
One major reason for South Africa’s high TB burden is the close link between TB and HIV. HIV weakens the immune system, making it more difficult for the body to control TB bacteria after infection. As a result, people living with HIV are about twelve times more likely to develop active TB disease than those without HIV (1). TB is also the leading cause of death among people with HIV, and in 2024, around 150,000 people died from HIV-associated TB (1).
While HIV is a major driver of TB, other health, environmental, and lifestyle factors also increase risk. Poor nutrition weakens the immune system, making it one of the strongest risk factors. Chronic diseases such as diabetes further raise the risk and are linked to poorer treatment outcomes (8). Diabetes increases the likelihood of active TB by about three times and doubles the risk of death during treatment, as well as relapse and drug-resistant TB (2,9). This is partly because high blood glucose impairs immune function, increasing susceptibility to latent infection and active TB disease (10). Lifestyle factors such as smoking and excessive alcohol use also heighten vulnerability (11).
Environmental and social conditions also play an important role. Overcrowded living environments allow TB bacteria to spread more easily between people. Poverty, limited access to healthcare, and poor living conditions, therefore, contribute significantly to TB transmission and disease development (5). These factors often interact, creating conditions in which the immune system becomes less able to contain infection. While not everyone has control over their living conditions or social environment, some factors that influence immune health can be improved. Among them, nutrition stands out as a critical and modifiable factor, as it directly influences immune function and the body’s ability to respond to disease.
Nutrition plays a fundamental role in supporting the immune system and enabling it to respond effectively to infections. Immune cells depend on an adequate supply of nutrients, including proteins, vitamins, and minerals, to function effectively. When nutritional intake is inadequate, immune responses can become weakened, increasing vulnerability to infectious diseases (12). Because nutrition is something individuals can influence in their daily lives, it offers an important opportunity to support immune resilience. A well-nourished body with balanced metabolic health is better equipped to mount an effective immune response and defend itself against infections (12).
At The Noakes Foundation, we focus on improving metabolic health through nutrition and promote a low-carbohydrate, high-fat (LCHF) real-food lifestyle. This approach aims to stabilise blood sugar and insulin levels, which are key drivers of metabolic health. By improving metabolic balance, nutrition can help support a stronger and more resilient immune system. While nutrition alone cannot prevent or treat TB, metabolic health plays an important role in how the body responds to infection. Supporting immune resilience through better nutrition can therefore form part of a broader strategy for protecting health.
TB remains a major global health challenge, particularly in countries such as South Africa. Addressing the epidemic requires strong public health systems, improved living conditions, and continued efforts to reduce poverty and inequality. At the same time, individuals can take meaningful steps to support their own health. While we cannot control every risk factor, we can make daily choices that strengthen our bodies and improve our resilience to disease. Choosing nourishing foods and supporting metabolic health are powerful ways to invest in long-term wellbeing. This World TB Day reminds us that the fight against infectious diseases happens not only through medicine and policy, but also through the everyday actions that help build stronger, healthier bodies
Raja Pfisterer
Raja Pfisterer is a qualified nurse from Basel, Switzerland, currently pursuing a Master’s degree in Health Sciences with a major in Economics and Policy at the University of Lucerne. She combines clinical nursing experience with a strong interest in public health and is passionate about linking health and nutrition to support individual wellbeing and more sustainable healthcare approaches.
Raja is currently interning with The Noakes Foundation in Cape Town, where she is gaining practical experience in public health and learning about nutritional approaches to chronic disease in under-resourced communities through Eat Better South Africa.
Her interests include health equity, strengthening sustainable healthcare systems, and developing public health policy interventions that improve health outcomes while promoting health literacy and empowering individuals to take an active role in their own well-being. She hopes to dedicate her future career to understanding the social determinants of health, addressing health inequalities, and improving population health, particularly among vulnerable groups.
Through her work with The Noakes Foundation, Raja believes people can be empowered to take control of their health step by step, helping build healthier communities and support long-term well-being.
References
(1) World Health Organization. (2025). Tuberculosis. https://www.who.int/news-room/fact-sheets/detail/tuberculosis
(2) Jeon, C. Y., & Murray, M. B. (2008). Diabetes mellitus increases the risk of active tuberculosis: A systematic review of 13 observational studies. PLoS Medicine. https://pmc.ncbi.nlm.nih.gov/articles/PMC2459204/
(3) Schuchart, S. (2017). Robert Koch und die Geschichte der Tuberkulose. Deutsches Ärzteblatt. https://www.aerzteblatt.de/archiv/medizingeschichte-robert-koch-und-die-geschichte-der-tuberkulose-277d2fcb-273f-48bf-ae05-41b3c8dc0adf
(4) World Health Organization. (2026). World TB Day 2026. https://www.who.int/campaigns/world-tb-day/2026
(5) World Health Organization. (2025). Global tuberculosis report 2025. https://iris.who.int/server/api/core/bitstreams/e97dd6f4-b567-4396-8680-717bac6869a9/content
(6) South African National Department of Health. (2025). TB recovery plan. https://www.health.gov.za/wp-content/uploads/2025/05/TB-Recovery-Plan-4_final_250526-1.pdf
(7) World Health Organization. (n.d.). South Africa intensifying efforts to end TB. https://www.afro.who.int/countries/south-africa/news/south-africa-intensifying-efforts-end-tb#:~:text=South%20Africa%20has%20a%20particularly%20high%20burden%20of,recorded%20an%20estimated%2054%20000%20deaths%20from%20TB
(8) Restrepo, B. I. (2013). Diabetes and tuberculosis. https://pubmed.ncbi.nlm.nih.gov/23305899/
(9) World Health Organization. (2021). TB and diabetes. https://www.who.int/publications/digital/global-tuberculosis-report-2021/featured-topics/tb-diabetes
(10) Martinez, N., & Kornfeld, H. (2021). Diabetes and tuberculosis: The role of hyperglycemia in immune dysfunction. https://pmc.ncbi.nlm.nih.gov/articles/PMC8664214/
(11) Medicover Hospitals. (n.d.). Risk factors of tuberculosis. https://www.medicoverhospitals.in/articles/risk-factors-of-tuberculosis#:~:text=A%20compromised%20immune%20system%20is%20one%20of%20the,immune%20system%2C%20making%20individuals%20more%20susceptible%20to%20TB
(12) Munteanu, C., & Schwartz, B. (2022). The relationship between nutrition and the immune system. Frontiers in Nutrition. https://pmc.ncbi.nlm.nih.gov/articles/PMC9772031/
