Geneva, Feb 4, IRNA -- The highest levels of multi-drug-resistant tuberculosis (MDR-TB) ever recorded have been revealed in a study published this month in the Bulletin of the World Health Organization.

A new global overview of TB drug resistance shows record levels of this serious public health threat, with some countries reporting MDR-TB in more than 65% of patients who have been previously treated for TB.

IRNA reporter in Geneva said that the study is the most comprehensive analysis available of all types of TB drug resistance using current global data.

Cases of MDR-TB have been reported in 80 countries, in some instances in almost 30% of all newly diagnosed cases. High rates of drug resistance were reported in Belarus, Estonia, the Russian Federation and Tajikistan.

“Surveillance of resistance to drugs is the cornerstone of TB control,” says Dr Matteo Zignol, from the Stop TB Department at the World Health Organization.

“Following 15 years of intensive efforts, we now have high quality data for two-thirds of countries in the world. At the same time, we don’t know the full extent of the problem because we lack data from many countries, in particular India and most of Africa where the TB burden is high.”

On the positive side, Zignol says China has introduced a nationwide TB survey that “represents a critical step towards addressing this problem in one of the world’s largest TB control programmes”.

“The number of TB patients diagnosed and treated for MDR-TB is increasing worldwide but much remains to be done,” says Zignol. “In 2010, only 16% of MDR-TB patients were given appropriate treatment.”

The World Health Organization supports national TB control programmes worldwide in setting up drug resistance surveillance so they can respond promptly to outbreaks of drug-resistant TB.

Mismanagement of TB treatment is the primary cause of multidrug resistance. Most cases of TB are cured by a strictly followed, six-month drug regimen that is provided to patients with support and supervision. Inappropriate or incorrect use of antimicrobial drugs, use of ineffective formulations or drugs of suboptimal quality can cause drug resistance.