Use of the strongest antibiotic has almost doubled in public hospitals in the past four years as drug resistance grows. The antibiotic, vancomycin, is the last line of defence against bacterial infections. Microbiologists warned that the emergence of the first superbug to be resistant to the drug - vancomycin-resistant Staphylococcus aureus (VRSA) - in Hong Kong meant the problem had reached a 'very dangerous' stage. In the 1994-95 financial year, public hospitals prescribed 68 doses of vancomycin. The figure jumped to 88 in 1995-96 and 116 in 1996-97. Last year, it was 125. 'Although more patients are being treated at public hospitals, the increase in the use of vancomycin is still alarming. I can say it is a very high level,' a microbiologist warned. 'It is a vicious circle - the increasing use of vancomycin has produced more superbugs, but when drug resistance is getting worse, doctors are inclined to use more vancomycin,' he said. Only public hospitals and clinics have statistics on the use of antibiotics. A Hospital Authority taskforce will hold an urgent meeting tomorrow to discuss how to combat VRSA. One of the proposals is to introduce a screening test at 10 public hospitals to detect a possible spread. However, a Department of Health consultant in community medicine, Dr Mak Kwok-hang, said the chances of VRSA spreading were slim. 'VRSA is more a hospital problem than a community one. Hospital patients generally need more antibiotic treatments and the hospital setting is more vulnerable to cross-infection.' Dr Mak said that the department's 63 clinics had been testing patients' specimens for bacteria and drug resistance patterns. Relevant information was reported regularly to the World Health Organisation. Lilian Lau Sau-han, spokeswoman for the Patients' Rights Association, said drug education given by private doctors was inadequate. 'Many private doctors do not tell patients they are taking antibiotics or fail to remind them to take the full course of drugs,' she said.