Statement of Christine F. Sizemore, Ph.D., Barbara E. Laughon, Ph.D., and Anthony S. Fauci, M.D., on World TB Day
March 24, 2009
This year, as we commemorate World TB Day, we renew our resolve to stop tuberculosis. Although mindful of the substantial challenges that confront us in the ultimate goal of eliminating tuberculosis, we are encouraged by recent progress in fighting this lethal infection. The theme of this year's World TB Day, "I Am Stopping TB," is enthusiastically embraced by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, as we continue working side by side with our international partners, other government agencies, communities and individuals affected by TB to stop this deadly disease.
TB is an ancient disease; however, it remains one of the major causes of disability and death throughout the world. Today, one-third of the world's population is thought to be infected with Mycobacterium tuberculosis (Mtb), the microbe that causes TB. An estimated 13.7 million people have the active form of the disease. In 2007, approximately 9.27 million people developed TB, of whom 1.37 million were HIV positive, and 1.75 million died, including 456,000 individuals co-infected with HIV.
With Mtb infection among people with HIV/AIDS rapidly on the rise, the two largest infectious disease pandemics of modern times are heading for a perilous collision. This threat is heightened by the rapid rise and spread of multidrug-resistant (MDR) TB, which is unresponsive to the first-line drugs isoniazid and rifampin, and extensively drug-resistant (XDR) TB, which resists most existing TB antibiotics. Although the true extent of drug resistance is unknown, estimates from the World Health Organization (WHO) suggest that an average of approximately 5 percent of all TB cases are MDR. Currently, the prevalence of XDR TB can only be inferred, because relatively few countries are able to test for XDR TB. While drug-sensitive TB comprises the largest burden of the disease globally, the continued emergence of drug-resistant Mtb strains raises serious concerns that gains in TB control may be rapidly reversed and treatment options reduced to what was available in the pre-antibiotic era.
TB is a serious public health issue throughout the world, particularly among populations in resource-poor nations. However, because no nation is immune from the effects of TB, stopping it requires a global commitment. In addition to our collaborations with other NIH Institutes and Centers, NIAID works with the U.S. Centers for Disease Control and Prevention, the U.S. Agency for International Development, and other federal agencies as part of the Federal TB Task Force and the NIAID-CDC Joint U.S. Partnership Implementing TB Elimination Research. NIAID leverages resources through international government and non-governmental agencies, industry and public-private partnerships. Through the WHO/Stop TB Partnership, NIAID coordinates research efforts with organizations that monitor disease and drug-resistance surveillance, treat TB patients -- including those also infected with HIV -- and support research training and TB control programs throughout the world.
As we enhance and strengthen our global partnerships to stop TB, we must also approach the science of TB with a global perspective. While TB by itself is a disease of immense public health consequence, we cannot forget that it occurs amid other public health challenges, particularly in resource-limited regions. Only through better understanding the impact of co-morbidities, or co-infections such as HIV, on disease progression, pathology and immune responses, will scientists be able to assess fundamental research needs, identify strategies for product development and conduct realistic clinical evaluation of new tools and approaches. Data from clinical studies will inform researchers whether new drugs, vaccines and diagnostics are broadly applicable or whether TB control will require a more targeted, setting-specific approach. As we develop new tools and evaluate the usefulness of evolving strategies and treatments, we must be keenly aware of the impact of overall patient health and co-morbidities.
During the past year, we have seen advances in many aspects of TB research, from the laboratory bench to treating patients in endemic settings. For example, NIAID-supported studies have revealed new information on mechanisms of action of anti-TB compounds that may facilitate the development of improved therapies. Genomic and field-based studies have provided insight into how drug-resistant TB develops. Clinical trials have shown that mortality among TB patients co-infected with HIV is drastically reduced when antiretroviral therapy is provided at the same time as TB therapy. Additional studies are under way to determine optimal strategies for the prevention, treatment and diagnosis of TB in the setting of HIV infection.
The development and implementation of rapid and sensitive diagnostics and tools to appropriately treat and monitor how individuals with TB respond to therapy are urgently needed if we are to control the spread of the disease and the emergence of drug resistance. Several NIAID-supported academic institutions, public-private partnerships and commercial entities are developing rapid tests for early detection of MDR and XDR TB. To aid the transition of diagnostic platforms to field use and advanced development, NIAID recently issued a request for proposals to develop a TB Clinical Diagnostics Research Consortium for assessing the performance of novel, early-stage TB diagnostics.
As we move forward to apply new fundamental knowledge to modernize health care interventions, we will continue to work with our global partners to integrate scientific disciplines and technologies and to study TB in the broadest possible context of other relevant and co-emergent diseases and morbidities. It is important that we balance basic research with product development, to ensure a steady pipeline of new diagnostics, drugs and preventive and treatment strategies.
NIAID commemorates this World TB Day with a reaffirmed commitment to stop TB by enhancing cooperation with our global partners and fostering collaboration among basic, applied and clinical researchers across multiple disciplines. It is only through such coordinated global efforts that progress can be made in stopping TB in its tracks.
For more information about TB, visit NIAID's Tuberculosis Web portal (http://www3.niaid.nih.gov/topics/tuberculosis/default.htm) and the HHS TB Web site (www.hhs.gov/tb/).
Anthony S. Fauci, M.D., is director of the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health. Christine F. Sizemore, Ph.D., is chief of the Tuberculosis and other Mycobacterial Diseases Section in the NIAID Division of Microbiology and Infectious Diseases. Barbara E. Laughon, Ph.D. is Senior Scientist for TB Drug Development Partnerships in the NIAID Division of Microbiology and Infectious Diseases.
This article was provided by U.S. National Institute of Allergy and Infectious Diseases.