Anthony S. Fauci, M.D.
Director, National Institute of Allergy and Infectious Diseases
Tuberculosis (TB) is the world’s leading cause of death from an infectious disease. Every three seconds, someone becomes ill from this airborne type of bacteria. Unfortunately, resistance of the TB bacteria to antimicrobial drugs renders some available therapies ineffective, making a global public health problem far worse. The number of new cases of drug-resistant TB has increased in recent years, with more than half a million new cases occurring globally each year. In 2015, drug-resistant TB was responsible for the deaths of 250,000 people worldwide.
Struggling against drug-resistant TB
A person with drug-sensitive TB who is inadequately treated or does not take TB medication as prescribed may develop drug-resistant TB. Increasingly, people are infected with strains that are already resistant to multiple drugs. Multi-drug resistant (MDR-TB) occurs when a strain of TB is resistant to isoniazid and rifampicin, the two most effective drugs used to treat TB. Extensively drug-resistant TB (XDR-TB) is MDR-TB that is also resistant to fluoroquinolones, a different class of antibiotic drugs, as well as one of the three injectable treatments used to treat TB. Roughly 10 percent of all MDR-TB diagnoses fall into the XDR-TB category.
Drug-resistant TB requires lengthy, difficult and expensive treatment regimens, substantially increasing health care costs and adding to the economic burden on families and societies. In the United States, it costs about $18,000 to treat someone with drug-sensitive TB. By comparison, treatment of a person with XDR-TB costs an average of $494,000. It takes 14,000 pills and countless painful injections over the course of two years or more to treat one patient with MDR-TB.
Digging deeper into TB treatments
The National Institutes of Health (NIH) conducts and supports research to address drug-resistant TB and the broader issue of antimicrobial drug resistance among all classes of microbes. Scientists are working to find new, faster ways to detect TB infection, including drug-resistant forms, so that appropriate treatment and TB control measures can begin immediately.
Researchers are also working to develop new treatments for drug-resistant forms of TB that are not only safe and effective, but better tolerated, of shorter duration and easier to adhere to. Additionally, NIH supports research toward the development of a vaccine to prevent TB infection.
TB is a serious disease, and its drug-resistant forms are of great concern to the public health community. Addressing the global problem of drug resistance is a top priority for NIH and critical to international efforts to effectively bring the TB pandemic under control.