Drug-resistant tuberculosis on the rise, UN health agency says
Rates of multi-drug-resistant tuberculosis – which takes longer to treat and requires more expensive drugs that have potentially serious side effects – are at an all-time high, according to a new report by the United Nations World Health Organization (WHO).
The study, entitled “Anti-Tuberculosis Drub Resistance in the World,” is the largest ever on the scale of drub resistance and is based on information collected between 2002 and 2006 on 90,000 TB patients in 81 countries.
The agency estimates that there are nearly half a million new cases of multi-drug-resistant TB, known as MDR-TB, annually worldwide, accounting for 5 per cent of the 9 million new cases every year.
“TB drug assistance needs a frontal assault,” said Mario Raviglione, Director of WHO's Stop TB Department. “If countries and the international community fail to address it aggressively now we will lose this battle.”
The highest rate of MDR-TB was found in Azerbaijan's capital Baku, where nearly one quarter of all new TB cases were reported to be multi-drug-resistant. WHO said that this type of TB is also widespread in Moldova; Donetsk, Ukraine; Tomsk Oblast, Russia; Tashkent, Uzbekistan; and China.
The report also spotted ties between HIV infection and MDR-TB, with surveys in Latvia and Donetsk, Ukraine, noting that the rate of MDR-TB is twice as high among tuberculosis patients living with HIV than it is among those without HIV.
For the first time, the worldwide survey included analysis of extensively drug-resistant tuberculosis, or XDR-TB, which is virtually untreatable. It has been recorded in 45 countries, but because few countries are currently equipped to diagnose it, limited data were available for inclusion in the current WHO study.
The agency reported notable successes, such as Estonia and Latvia, which were deemed MDR-TB 'hotspots' more than a dozen years ago but whose rates are now stabilizing.
However, given that only six countries in Africa – the continent with the highest incidence of TB globally – were able to submit data for the report, WHO pointed out that the magnitude of the respiratory disease in some parts of the world remains unknown.
“It is likely there are outbreaks of drug resistance going unnoticed and undetected,” said WHO tuberculosis expert Abigail Wright, the report's principal author.