Drug-resistant superbugs, a legacy of Sars

Doctors and scientists are fighting the emergence of drug-resistant superbugs after heavy use of strong antibiotics during and after the 2003 Sars outbreak.

University of Hong Kong microbiologist Ho Pak-leung, who helped conduct a pilot antibiotics audit scheme with Queen Mary Hospital, said: 'Some doctors used second-line antibiotics as first defence on patients, especially on those with lung infections, in order to shorten their stay in hospitals. There is a peak on the use of strong antibiotics in Hong Kong hospitals during and after the Sars outbreak.'

Professor Ho learned that several public hospitals had noticed the emergence of bacteria that could not be killed by carbapenem, the strongest type of antibiotic. One hospital has recorded more than 100 cases.

He said patients infected by carbapenem-resistant bacteria could only be treated by other methods such as surgery and use of drugs that are still on clinical trial.

At Queen Mary Hospital, for example, the use of carbapenem in 2003 rose by 71 per cent compared with 2001.

The hospital launched a pilot scheme in January last year to better control the use of antibiotics. The scheme audits the use of 22 so-called 'big gun' antibiotics - including carbapenem - by the intensive care unit.

Intensive care units are high-risk areas where drug-resistant bacteria can be found, as more than 70 per cent of ICU patients require antibiotic treatment.

Under the programme, ICU doctors have to give reasons for using antibiotics. The prescriptions will then be audited by pharmacists and microbiologists.

The hospital's consultant physician in intensive care, Chan Wai-ming, said the use of the big gun antibiotics at the ICU had dropped by 20 per cent in 2005 from a peak in 2003. The use of carbapenem, in particular, was cut by about half.

Infectious-disease specialist and former legislator Lo Wing-lok said the increasing emergence of antibiotic-resistant bacteria in hospitals was a global trend that was set to continue.

But he added that the outbreak of severe acute respiratory syndrome, during which strong drugs were widely used for a relatively short period, was not the only cause of the problem and that the long-term use of strong drugs was the core issue.

'The situation will be getting more and more serious,' he said. 'It takes a long time and large investments to develop new drugs, but their lifespans are getting shorter and shorter.'

Additional reporting by Benjamin Wong