Francesca Tomasi received her B.A. from the University of Chicago and is now a microbiologist.
What do Franz Kafka, Emily Brontë, King Henry VII of England, Pocahontas, and Erwin Schrodinger have in common? They all probably appeared at one time or another on your school syllabi, and they all died of tuberculosis. Also known through different times in history as Consumption, Phthisis, Scrofula, White Plague, and Pott’s, tuberculosis has ravaged the human race for thousands of years. To this day, it continues to infect humans as it cleverly counteracts the efforts of modern medicine.
Approximately 6,000 years ago is when it all may have begun, according to recent research. Scientists reconstructed a tuberculosis genome from Peruvian skeletal remains and concluded the causative agent of the White Plague, Mycobacterium tuberculosis, first originated around this time. About 1,000 years later, the bacterium invaded its first human, and quickly established itself as an endemic illness via trade routes. Soon thereafter, domesticated animals in Africa acquired the disease, and migratory sea creatures like seals eventually crossed the unforgiving ocean, carrying the even more unforgiving bug with them to the Americas.
Historical records are rife with descriptions of illnesses that fit the description of tuberculosis, which causes a nasty cough that produces blood or sputum (when it attacks its predominant target, the lungs), chest pain, fatigue, weight loss, lack of appetite, fever, chills, and sweating. Eventually, if left untreated, active tuberculosis infection causes death. The Egyptians documented a “pulmonary consumption” in their medical treatise, the Ebers papyrus. The Old Testament cursed individuals who strayed from God with the same symptoms. The Ancient Indian Vedas reference tuberculosis as Scrofula, advising ill individuals to mix breast milk and various meats with alcohol and rest. Traditional Chinese medicine also described TB symptoms but called it Phthisis. Hippocrates outlined the characteristics and symptoms of tuberculosis in his work. Tuberculosis swept through the Middle Ages, past the Renaissance, into the 17th, 18th, and 19th centuries. It killed millions of people and lay latent (infected individuals but did not cause disease for reasons still being studied today) in millions more. Finally, in 1882, Prussian physician and a father of microbiology, Robert Koch, looked at coagulated blood serum under a microscope and discovered the cause of tuberculosis: a small, rod-shaped bacterium known as a bacillus. He publicized his findings on March 24, 1882, in a famous lecture titled Über Tuberculose. March 24th is still known as World Tuberculosis Day.
In the 19th century, tuberculosis facilities known as sanatoria were established to quarantine patients and keep them in ambient environments that may clear their systems and heal them. Eventually, sanatoria were eliminated as they failed to actually cure anybody, and tuberculosis was still an urgent health problem going into the twentieth century. In 1906, Albert Calmette and Camille Guérin developed the Bacille Calmette-Guérin (BCG) vaccine, an attenuated bovine-strain tuberculosis. It was first used in humans in 1921 and is still administered in several European countries today. Despite its widespread use, BCG is by no means a robust or reliable vaccine. In 1944, the natural antibiotic streptomycin was isolated from Streptomyces bacteria and the drug was found to kill M. tuberculosis. 8 years later, isoniazid was developed as the first oral anti-tuberculous drug. Rifampin followed in the 1970s. Together, these antibiotics significantly reduced TB cases through the 1980s. Treatment regimens still required months of therapy, and these first-line tuberculosis drugs were by no means without side effects for patients, making it difficult for patients to take their full course of medications. By the end of the 1980s, drug-resistant strains of tuberculosis emerged, and incidence of the disease began to rise again. Infrastructural issues in different parts of the world, combined with the emergence of HIV, which severely weakens the immune system, contributed to the resurgence of TB. Patients failed to complete their course of antibiotics, which allowed the bacteria to evolve and become armed against the aforementioned drugs. In 1993, the World Health Organization declared tuberculosis a global health emergency. To this day, approximately 500,000 new cases of multi-drug resistant tuberculosis (MDR-TB) are estimated to occur worldwide, and extensively drug resistant (XDR-TB) strains have also emerged.
The World Health Organization published its 2015 Tuberculosis Report in October, and within it came the news that TB is now the leading infectious killer in the world, officially stealing the infamous title from HIV/AIDS. “More lives are lost annually to TB than even HIV/AIDS,” says Hannah Bowen, Director of ACTION Global Health Advocacy Partnership. “This is a testament to the impact of aggressive action and ambitious funding on changing the course of a global epidemic like HIV. It’s also a reminder of steady, but slow and fragile, progress against TB.” The observed surge in TB cases last year is a direct manifestation of the fact that the more we look for TB around the world, the more we find it. Diagnosis is hard, and diagnosis is especially hard in resource-poor countries, which account for a majority of cases. Furthermore, according to the WHO Report, 2 out of every 5 people with tuberculosis do not receive the treatment they need. It goes without saying that if people aren’t receiving treatment, even more are going undiagnosed.
Tuberculosis has stood the test of time, but organizations around the globe are steadily mobilizing forces. The global Stop TB Strategy seeks to eliminate tuberculosis as a public health problem by 2050. To reach this goal, universal access to high-quality care for all individuals with TB is an utmost priority. Directly-observed therapy, in which a healthcare provider physically watches TB patients take their drugs at appropriate times, is an essential procedure for treating an illness as slow-growing and persistent as TB. In addition, preventive efforts to protect, educate, and empower vulnerable populations from TB, MDR-TB, and TB/HIV co-infection are underway. Finally, increased funding and interest in research to develop novel diagnostics, therapeutics, and vaccines will bring us even closer to a TB-free world.