M/XDR-TB: A deadly, infectious disease that knows no borders
In 2008–2009, the highest ever number of MDR-TB1 cases were reported to WHO, with an estimated half a million new MDR-TB cases emerging annually. Drug-resistant TB has a higher mortality rate, and is significantly more difficult and costly to treat than drug-susceptible TB.
XDR-TB2, a subset of MDR-TB of highly drug-resistant strains that have significantly worse outcomes, has now been reported in more than 50 countries. XDR-TB develops as a result of mismanagement of MDR-TB. Today, only some 3% of these estimated cases of MDR-TB are being treated according to WHO standards, while many more MDR-TB patients are mismanaged by various public and private providers.
The global threat of MDR-TB and XDR-TB (M/XDR-TB) can be halted if TB control measures are urgently put in place across the whole health system as recommended under the Stop TB Strategy. If countries do not, they will face the prospect of a bigger M/XDR-TB epidemic.
"To allow this form of TB to become widespread would be a setback of epic proportions", WHO Director-General, Dr Margaret Chan, in her address to the 61st World Health Assembly.
Skyrocketing health costs
In 2009, US$1.2 billion will be required for the diagnosis and treatment of M/XDR-TB patients, with US$11 billion for the period 2010-2015, not including out of pocket costs to patients themselves.
These costs will place significant pressure on government health budgets and already challenged public health systems in developing, middle income countries and in-transition economies.
Countries must respond urgently or face the prospect of vastly heavier financial demands in the future.
The costs of inaction clearly outweigh the costs of action. A major scale up of our global response to prevent drug resistant TB simply cannot wait.
1 Multidrug-resistant tuberculosis (MDR-TB) is defined as resistance to the two most powerful first-line anti-TB drugs(isoniazid and rifampicin).
2 Extensively drug-resistant tuberculosis (XDR-TB) is defined as MDR-TB plus resistance to the most powerful second-line anti-TB drugs (any fluoroquinolone and any of the three injectable drugs: amikacin, capreomycin and kanamycin).
MDR-TB and XDR-TB is defined throughout this site as M/XDR-TB.