USIS Washington File - March 5, 2008
Washington -- Drug-resistant forms of the airborne infectious
disease tuberculosis (TB) are spreading around the world, raising
concern among health leaders and prompting a global response to
these emerging and often lethal contagions.
The response includes a new World Health Organization (WHO)
report, Anti-Tuberculosis Drug Resistance in the World, based on
data collected between 2002 and 2006 on 90,000 TB patients in 81
nations.
The report -- which presents findings from the largest survey to
date on the scale of drug resistance in TB -- targets
multidrug-resistant (MDR) TB, which is resistant to at least two
of the best (first-line) anti-TB drugs, isoniazid and rifampicin.
"What is disturbing to me and all those involved," Dr. Mario
Raviglione, director of the WHO Stop TB Department, told the
House Foreign Affairs Subcommittee on Africa and Global Health
February 27, "is that we are now seeing the highest rates of
MDR-TB ever recorded in the history of TB control."
MULTIDRUG RESISTANCE
Those with MDR-TB must be treated with more expensive, less
effective second-line drugs for 18 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, an often deadly
type of MDR-TB that is resistant to first- and second-line drugs.
WHO estimates that nearly 500,000 MDR-TB cases occurred worldwide
in 2006, with more than 110,000 deaths. According to the study,
which for the first time includes an analysis of extensively
drug-resistant TB, the virtually untreatable XDR-TB has been
recorded in 46 countries.
The highest rates of MDR-TB among new cases were reported from
Azerbaijan (22.3 percent), Eastern Europe's Moldova (19.4
percent), Ukraine (16 percent) and Russia's Tomsk Oblast (15
percent).
The report also found a link between HIV infection and MDR-TB.
Surveys in Latvia and Ukraine found nearly twice the level of
MDR-TB among TB patients living with HIV than among those who
were not infected with the virus.
In 2006, WHO launched the Stop TB Strategy, the core of which is
a TB-control approach called DOTS (directly observed
therapy-short course), created in 1995. It includes political
commitment with sustained financing, case detection through
quality-assured bacteriology, standardized treatment with
supervision and patient support, an effective drug supply and
management system, and a monitoring and evaluation system.
More than 22 million patients have been treated under DOTS-based
services and an expanded strategy recognizes key challenges of
TB/HIV and MDR-TB.
URGENT ACTION
In the United States, the Centers for Disease Control and
Prevention (CDC)/National Institutes of Health (NIH), the U.S.
Agency for International Development (USAID), and the President's
Emergency Plan for AIDS Relief (PEPFAR) support WHO TB-control
efforts, and the U.S. government helped develop the WHO Global
MDR-XDR TB Plan.
CDC works closely with other agencies to prevent TB globally, CDC
Director Julie Gerberding told the House panel, "and [Health and
Human Services/]CDC also supports WHO and the Stop TB Partnership
on a number of important activities, including providing
technical assistance to the Global Drug Facility, which works to
supply quality medications for TB programs."
Complementary research efforts of CDC and NIH play a key role in
the development of new drugs and new regimens for drug-resistant
TB, she added.
At USAID, Kent Hill, assistant administrator for global health,
said, the core of work on TB is focused on developing the
capacity of countries affected by TB to put in place effective
programs to combat and control TB.
"Between 2006 and 2007," he added, "USAID provided nearly $600
million for TB programs worldwide, including about $166 million
directed specifically to Africa, This is in addition to funding
for TB/HIV provided under PEPFAR. USAID supports TB programs in
37 countries," focusing on 19 countries with a high burden of TB,
MDR-TB or TB/HIV.
FUNDING GAP
In its effort to help fight TB, PEPFAR increased funding for
HIV/TB five-fold, U.S. Global AIDS Coordinator Dr. Mark Dybul
said, from $26 million to $131 million, from fiscal years 2005 to
2007, and $150 million is planned for fiscal 2008.
"Whether it is drug resistant or not, TB is an airborne,
potentially deadly disease," Dybul said. "Because its effect on
the immune system makes HIV-infected people more susceptible to
infection, HIV is the greatest risk factor for developing
tuberculosis."
"Urgent action is needed to build strong TB control programs with
mainstreamed MDR-TB treatment elements and rapid scale up of
HIV/TB interventions," Raviglione said. "Strengthened
laboratories for TB diagnosis and surveillance are essential,
along with infection control and more health providers and
communities prepared and motivated to ensure effective and safe
treatment for patients."
WHO estimates that $4.8 billion is needed for overall TB control
in low- and middle-income countries in 2008, with $1 billion for
MDR-TB and XDR-TB. There is a finance gap of $2.5 billion,
including a $500 million gap for MDR-TB and XDR-TB combined.
More information about the Stop TB Strategy is available on the
WHO Web site.
Additional information about tuberculosis is available at the CDC
Web site.