TB bacteria
TB bacteria are fighting back against drugs

Drug resistant tuberculosis is posing a growing threat in the UK, probably fuelled by immigration, say experts. A Health Protection Agency team examined 28,620 TB infections in England, Wales and Northern Ireland between 1998 and 2005.

They found the proportion of cases resistant to any of the first-line drugs rose from 5.6% to 7.9%. The British Medical Journal study also found a small increase in cases of multi-drug resistant TB (MDR-TB).

However, although the number of people becoming infected with drug-resistant TB has almost doubled, from 170 in 1998 to 336 in 2005, they still make up a small proportion of the total number of TB infections.

The HPA researchers found a significant increase in resistance to one particular drug, isoniazid, outside London.

Many of these patients came from sub-Saharan Africa and the Indian subcontinent, where they may have developed immunity to the drug.

The researchers said measures to control outbreaks of TB among prisoners and drug users were not up to scratch.

They said the shortcomings of the current system were illustrated by the fact that an outbreak of drug resistant TB among prison inmates and drug users which began in London in 1999 was still producing new cases.

Detection key

The HPA team, led by Dr Michelle Kruijshaar, concluded: "The observed increases highlight the need for early case detection, rapid testing of susceptibility to drugs, and improved treatment completion."

Professor Stephen Spiro, of the British Lung Foundation, said: "GPs and clinicians, particularly those based in London, must be vigilant and make sure that people with symptoms suggestive of TB are referred promptly for further investigation to a TB clinic or for an X-ray and that people with the disease are offered support to make sure they complete their treatment."

It had been hoped that antibiotic drugs had largely neutered the impact of TB.

But a report by the World Health Organization in February revealed that globally MDR-TB have hit the highest levels ever recorded.

The WHO survey also found cases of extensively drug resistant TB which is virtually untreatable in 45 countries.

Professor Peter Davies, lead clinician for the National Multi-Drug Resistant Tuberculosis Service (MDRTB Service), warned individual doctors had very little experience in managing drug resistant cases.

The MDRTB Service provides a rapid reaction force of experts who can offer immediate advice and management help when TB outbreaks occur.

Doctor Mario Raviglione, director of Stop TB, part of the World Health Organisation, warned the drugs needed to treat a patient with MDR-TB cost 100 times those needed to treat a standard TB case.

He said: "The study underlines once again that TB care and control measures must be seriously implemented to cure people and prevent drug resistance.

"The study also proves that no country, no matter how rich and developed, will ever achieve elimination of TB until TB is under control globally.

James Lewis, of the London School of Hygiene and Tropical Medicine, said there was clearly no room for complacency about MDR-TB.

However, he said: "Given the population size of England, Wales and Northern Ireland, multi-drug resistant TB is still rare and remains the exception."