Tuberculosis

March 24 is World TB Day

Thursday, March 24, is designated as World TB Day, calling attention to a disease that is a major killer worldwide, especially of people with HIV/AIDS.

According to a review article in the March 18, 2011, online edition of the Lancet, tuberculosis causes an estimated 1.7 million deaths each year, and the number of new cases worldwide (more than 9 million) is higher than at any time in history.

"Due to the devastating effect of HIV on susceptibility to tuberculosis," wrote authors Stephen Lawn and Alimuddin Zumla, "sub-Saharan Africa has been disproportionately affected and accounts for four of every five cases of HIV-associated tuberculosis."

The U.S. Centers for Disease Control and Prevention (CDC) Division of Tuberculosis Elimination has developed TB Day materials and resources in English and Spanish. Visit the website at www.cdc.gov/tb/WorldTBDay for resources, web tools, posters, and a list of domestic and international World TB Day events.

The Stop TB Partnership also has TB information in multiple languages at www.stoptb.org/events/world_tb_day/2011.

The CDC's Public Health Grand Rounds on March 24 will focus on "TB & HIV: A Deadly Duo." The program will be broadcast live at 11am Eastern Time/8am Pacific Time at http://cdc.wl.miisolutions.net/live/cdc/6.

According to CDC Director Thomas Frieden, "HIV is the single most powerful risk factor for TB disease and one of the leading causes of death among people infected with HIV."

"While people with HIV who have TB can be effectively diagnosed and treated, he continued, "more effort is needed to diagnose and treat TB promptly and effectively, and to scale-up preventive treatment for TB."

Below is a statement from Christine Sizemore and Anthony Fauci from the National Institute of Allergy and Infectious Diseases in recognition of the day.

World TB Day - March 24, 2011

Statement of Christine F. Sizemore, PhD, and Anthony S. Fauci, MD
National Institute of Allergy and Infectious Diseases
National Institutes of Health

The theme of World TB Day 2011 -- "On the move against TB: Transforming the fight towards elimination" -- reflects renewed momentum to approach the global problem of tuberculosis with greater intensity and seriousness of purpose. This growing interest is broad-based, emerging from leaders in public health to laboratory scientists, from physicians to activists.

Today, about one-third of the world's population is infected with Mycobacterium tuberculosis (Mtb), the bacterium that causes TB. Most people have no symptoms because the bacterium is inactive, or latent, but individuals with symptoms of active TB disease can infect others. According to World Health Organization (WHO) estimates, in 2009 more than 14 million people had active TB, leading to 1.7 million deaths, or 4,600 deaths each day. Among people infected with the bacteria, those who have certain other conditions, such as HIV/AIDS and diabetes, are more likely to develop active TB and to die from it. Because of this deadly synergy, TB has become the leading cause of death among people with HIV/AIDS.

Although TB control programs have led to a decline in cases worldwide, the emergence and spread of drug-resistant strains of Mtb challenge the way we currently approach TB diagnosis and treatment. Extensively drug-resistant TB, while relatively rare, has been confirmed in 58 countries, including the United States, and likely is present in many more. It has become necessary not just to identify the infection but also to determine the proper therapy for patients at the earliest stages of disease.

Recent developments have created confidence that TB control strategies can be improved to stay abreast of the changing nature of the pandemic. For the first time in decades, a robust pipeline of candidate TB drugs, vaccines, diagnostics, and treatment and prevention strategies are being evaluated in clinical trials. WHO recently endorsed a diagnostic test that enables health care providers to identify drug-resistant TB directly from patient specimens within about two hours rather than waiting months for a conclusive diagnosis. Drugs are being developed that, when combined in novel ways, may significantly improve the way we treat patients with TB. Vaccines are being developed that may one day prevent the disease, even in persons who are already infected with Mtb.

While such advances are crucial to improve patient care, a true transformation in the fight against TB can occur only if we simultaneously deepen our understanding of TB as a disease. For example, a noninvasive means to determine whether an individual is containing the infection or progressing to active disease -- what's called a biomarker -- would be of enormous benefit to patient care and for conducting clinical trials of therapies and vaccines. Additionally, although 90 percent of people infected with Mtb never develop active disease, latent TB infection remains largely mysterious. Increasing our knowledge in these and other fundamental areas is a research priority for the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. New and improved laboratory and clinical tools, as well as collaborations between all disciplines of biomedical research, are now being engaged to characterize the interactions at play during the course of Mtb infection and TB disease. The extraordinary complexity of the TB disease process makes it well-suited to being examined as an integrated whole, an approach successful in yielding insights into other complicated diseases.

Together with our global partners, we at NIAID are encouraged by recent progress in TB research. By fostering a comprehensive TB research agenda and innovation at all levels, and by addressing TB with research tools appropriate to the health care challenges we face in the 21st century, we can continue to make great strides. World TB Day reminds us that although TB has afflicted mankind for millennia, we have yet to understand it in modern terms. We must use cutting-edge technologies to ask and answer fundamental questions that have never been adequately addressed. Only in this way will we transform our fight against TB towards elimination of this ancient scourge.

For more information about TB, visit NIAID's Tuberculosis Web portal and the HHS TB Web site.

Anthony S. Fauci, MD, is director of the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health. Christine F. Sizemore, PhD, is chief of the Tuberculosis and Other Mycobacterial Diseases Section in the NIAID Division of Microbiology and Infectious Diseases.

Sources

S Lawn and AI Zumla. Tuberculosis. The Lancet (summary). March 18, 2011 (Epub ahead of print).

T. Frieden. CDC e-HAP email newsletter. March 21, 2011.

CF Sizemore and AS Fauci. World TB Day Statement. March 21, 2011.