WASHINGTON (RPRN) 03/25/09-Tuberculosis (TB) is a 500,000-year-old contagious lung disease that kills someone around the world every 20 seconds. A diagnostic test was developed 125 years ago, its vaccine 80 years ago and drug treatments 40 years ago.
Worldwide, 9.3 million people suffer from the disease and 1.8 million people will die from it this year, according to the World Health Organization (WHO), placing TB just behind HIV/AIDS as a cause of global fatalities. Billions of dollars, through governments and foundations, are dedicated to stopping the airborne spread of TB, and the greatest need in the quest for treatments, diagnostics and vaccines is innovation.
“World TB Day [March 24] reminds us that it’s an ancient disease” and the tools for combating it “have been used for a century or 50 years or 40 or 20, depending on which tools you’re talking about,” Diana Weil, coordinator for policy and strategy in WHO’s Stop TB Department, told America.gov. “We have chances now to innovate, but we also have chances to do better with what we’ve got.”
World TB Day marks the day in 1882 when Dr. Robert Koch detected the cause of tuberculosis, the TB bacillus, and took the first step toward diagnosing and curing the disease.
$14 CAN SAVE A LIFE
TB is treated with a six- to nine-month course of “first-line” (most effective) drugs that cost about $14. If patients do not complete the drug course or are treated improperly, they can develop a multidrug-resistant (MDR) form of the disease.
Those with MDR TB must be treated with more expensive, less effective second-line drugs for 18 months to 24 months. If they do not complete this course or are treated with the wrong drugs, they can develop extensively drug resistant (XDR) TB, whose bacteria strains are resistant to first- and second-line drugs.
Fewer than 30 percent of XDR TB patients who are otherwise healthy and whose immune systems are not compromised can be cured. More than half of those with XDR TB die within five years of diagnosis, and there could be 50,000 cases of XDR TB worldwide.
When infected people cough, they spray infectious particles that other people inhale, Dr. Peter Small, senior program officer for tuberculosis at the Bill and Melinda Gates Foundation, said in a March 17 briefing at the Center for Strategic and International Studies in Washington.
In many cases, the immune system keeps the TB bacteria under control after a person becomes infected – a condition known as “latent infection.” The bacteria can become active when something – advancing age or a medical condition such as HIV – reduces a person’s immunity.
“A third of the world is latently infected and lives in this tenuous balance between a pathogen and their immune system,” Small said. “This central role of the immune system in checking TB is most dramatic in sub-Saharan Africa, where the convergence of the HIV and TB epidemics has totally changed the disease.”
Innovation in creating new diagnostics, drugs and vaccines is the main focus of the Gates Foundation TB program, Small said.
“A four-month treatment regime is in a phase three trial [the final test of a drug’s effectiveness] by one of our grantees, the Global Alliance for TB Drug Development,” he said, “and three new drug candidates have exciting phase two trial [the initial test of a drug’s effectiveness] results.” Small expects a drug regime to be available for drug-resistant cases by 2016-2017.
Six vaccines are in, or soon will begin, human clinical trials, Small said. Each has the potential to protect people from TB. He expects an improved TB vaccine to be available in or near 2016.
Through the Foundation for Innovative New Diagnostics, Small said, molecular diagnostics are becoming available that will report in hours rather than months whether a person has drug-resistant TB. He expects rapid diagnostic tests to be available by 2012.
Political commitment to the TB fight is growing worldwide, he said, including in China, Brazil and India. The Stop TB Partnership is holding a partners forum March 23-25 in Brazil that is expected to attract more than 1,700 attendees.
In April, ministers from countries with the most cases of MDR- and XDR-TB will meet in China to address MDR-TB. Bill Gates will open the meeting, which is organized by WHO, the Ministry of Health of the People’s Republic of China and the Gates Foundation.
FUNDING THE FIGHT
TB funding is increasing but gaps remain. The recently passed U.S. Omnibus Appropriations Act includes $162 million for TB funding through the State Department’s foreign operations account, a $9.5 million increase from 2008 levels. The U.S. Agency for International Development increased its TB funding from $22 million in 2000 to $93 million in 2005.
In 2008, the National Institutes of Health spent about $160 million on TB research, and the recent $48 billion reauthorization for the President’s Emergency Plan for AIDS Relief (PEPFAR) includes $4 billion for TB treatment and prevention over the next five years.
The Global Fund to Fight AIDS, Tuberculosis and Malaria has helped mobilize global resources, Small said. About 14 percent of its funding went to TB. To date the organization has treated 4.6 million TB cases.
But the Stop TB Partnership says a funding gap of $31 billion exists, including $22 billion for program implementation and $9 billion for treatment and diagnostic tools over the next decade.