Measures to combat XDR-TB worldwide

Health experts have confirmed that the emergence of extensively drug-resistant tuberculosis (XDR-TB) poses a serious threat to public health, particularly when associated with HIV.

At its first meeting, the World Health Organization (WHO) Global Task Force on XDR-TB also outlined a series of measures that countries must put in place to effectively combat XDR-TB. In addition, the Task Force will help mobilize teams that can respond to requests for technical assistance from countries, and be deployed at short notice to XDR-TB risk areas.

These were among a series of outcomes issued by the Global Task Force meeting held on 9 and 10 October in Geneva. The meeting was urgently convened to review the latest available evidence on the impact of highly resistant tuberculosis, including when associated with HIV.

Addressing the Task Force, Acting Director-General of WHO, Dr Anders Nordström, said the Organization was "absolutely committed" to supporting country efforts to fight TB in all forms.

"It is critical that urgent steps are taken to address XDR-TB, especially in areas of high HIV prevalence," said Dr Nordström. "At the same time we should not lose sight of the need to make long-standing improvements to strengthen TB control, and build the necessary capacity in health services to respond to drug-resistant tuberculosis."

Along with a call for countries to strengthen TB control - the key to preventing TB drug resistance - consensus was reached on an XDR-TB case definition (see below). In high HIV prevalence settings, there was also agreement that control of XDR-TB will not be possible without close coordination of TB and HIV programmes and interventions.

The Task Force also made specific recommendations on drug-resistant TB surveillance methods and laboratory capacity measures; implementing infection control measures to protect patients, health care workers and visitors (particularly those who are HIV infected); access to second-line anti-TB and antiretroviral drugs for countries; communication and information-sharing strategies related to XDR-TB prevention, control, and treatment including co-management with antiretroviral therapy; and research and development of new TB drugs, vaccines and diagnostic tests.

WHO and Task Force members will now coordinate with national and international partners involved in TB as well as HIV prevention, care and treatment to take the recommendations forward. They will also develop a plan that identifies the resources required to implement these outcomes and the overall emergency response.

Drug-resistant TB has emerged as an increasing threat to TB control but a WHO / US Centers for Disease Control and Prevention study, published earlier this year, documented for the first time cases of tuberculosis that were extensively resistant to current drug treatments. XDR-TB was identified in all regions of the world, though it is still thought to be relatively uncommon.

Last month, concerns about the emergence of XDR-TB were heightened by reports and studies from KwaZulu-Natal province in South Africa of high mortality rates in HIV-positive people with XDR-TB. This led to warnings that XDR-TB could seriously threaten the considerable progress being made in countries on TB control and the scaling up of universal access to HIV treatment and prevention.

Among the first countries to request assistance to strengthen its national emergency XDR-TB response, and the extra challenges posed by HIV, is South Africa. The South African Department of Health is to host an XDR-TB meeting on 17 and 18 October, with participation from WHO and representatives from other affected southern African countries.

WHO Global Task Force on XDR-TB, October 2006 - Outcomes and Recommendations

Preventing XDR-TB through strengthening TB and HIV control
To prevent the appearance and spread of drug-resistant TB, the Task Force underlined as a priority the need for the immediate strengthening of TB control in countries, as detailed in the new Stop TB Strategy and Global Plan to Stop TB 2006-2015. This should be done in coordination with scaling up universal access to HIV treatment and care. WHO and Task Force members will help mobilize teams of experts that can be deployed in the field, at the request of countries, to assist in strengthening TB control, and where relevant HIV control.

There were also specific recommendations on:

Management of XDR-TB suspects in high and low HIV prevalence settings:
Accelerate access to rapid tests for rifampicin resistance, to improve case detection of all patients suspected of multidrug-resistant TB (MDR-TB) so that they can be given treatment that is as effective as possible. Rapid diagnosis is potentially life saving to those who are HIV positive.

Programme management of XDR-TB and treatment design in HIV negative and positive people:

• Adhere to WHO Guidelines for the Programmatic Management of Drug Resistant TB;
• Improve MDR-TB management conditions;
• Enable access to all MDR-TB second-line drugs, under proper conditions;
• Ensure all patients with HIV are adequately treated for TB and started on appropriate antiretroviral therapy.

Laboratory XDR-TB definition:
XDR-TB is defined as resistance to at least rifampicin and isoniazid from among the first line anti-TB drugs (which is the definition of MDR-TB) in addition to resistance to any fluoroquinolone, and to at least one of three injectable second-line anti-TB drugs used in TB treatment (capreomycin, kanamicin, and amikacin).

Infection control and protection of health care workers with emphasis on high HIV prevalence settings:
Accelerate wide implementation of recommended infection control measures in health care settings and other risk areas in order to reduce the ongoing transmission of drug-resistant TB, especially among those who are HIV positive.

Immediate XDR-TB surveillance activities and needs:
Strengthen laboratory capacity to diagnose, manage and survey drug resistance; Commence rapid surveys of drug-resistant TB so that the extent and size of the XDR-TB epidemic, and its association with HIV, can be determined.

Advocacy, communication and social mobilization:

• Initiate information-sharing strategies that promote effective prevention, treatment, control of XDR-TB at global and national levels and also in high HIV prevalence settings;
• Strengthen communication with affected communities and individuals;
• Develop a fully-budgeted plan with the resources and funding required to address XDR-TB, including through necessary improvements in overall TB control and HIV care in the immediate and medium term;
• Initiate resource mobilization.

Planning is also underway for a focused meeting in the near future on research and development issues relating to TB, including promoting the development of the new diagnostics, drugs and vaccines that are urgently needed. A meeting on antiretroviral therapy and XDR-TB is also planned.

For more information contact:

Glenn Thomas
Stop TB Department
WHO Geneva
Mobile: +41 79 509 0677
E-mail: [email protected]

Iqbal Nandra
HIV Department
WHO Geneva
Mobile: +41 79 509 0622
E-mail: [email protected]