Drug resistant tuberculosis has hit the highest levels ever recorded, according to a report on the disease from the World Health Organisation (WHO). In a survey of over 90,000 TB patients in 81 countries, the WHO found that levels of multi-drug resistant (MDR) TB were far higher then expected.
The survey also found cases of extensively drug resistant TB which is virtually untreatable in 45 countries. The findings have taken the organisation by surprise.
MDR-TB is resistant to at least the two most powerful anti-TB drugs, isoniazid and rifampicin.
As a result patients do not respond to the standard six month treatment and have to take more expensive - and more toxic - drugs for up to two years. It is especially prevalent in the former Soviet Union: in Azerbaijan's capital, Baku, almost a quarter of all new TB cases are multi-drug resistant.
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http://news.bbc.co.uk/2/hi/health/7265464.stm