EUREKA moments in medical science arrive by different means. They can be the result of years of dogged research or a slice of good fortune. Often they are a combination of both. Scientists at Heriot-Watt University in Edinburgh are some way off crying "eureka!" in their research to find an antibiotic to counterMRSA, the socalled "superbug". But years of scientific leg-work and a chance discovery have come together to raise expectations that controlling hospital infections could become easier in future.

Researchers at the university have developed anti-MRSA antibiotics produced by bacteria discovered in seaweed in the Firth of Forth. They have learned that, in the laboratory, the bacteria produce the antibiotics only when kept on a particular brand of kitchen sponge-scourer apparently available in only one supermarket chain. The scientists have approached the chain to find out who manufactures the sponge so that they can identify what makes it the ideal home for the microbes, which yielded the antibiotic when grown on discs of the sponge in containers of meat broth.

It reads like the meal from hell but, if scientists get to the bottom of the mystery and the antibiotic successfully completes clinical trials in the years to come, it could spell the end for the superbug. That day, although a long way off, cannot come too soon. MRSA is resistant to conventional antibiotics. It is ruthless in exploiting weaknesses in hospital patients and in standards of hygiene. It, alone, kills some 450 people a year in Scotland.

It is possible that, in the near future, a strain of the MRSA family could emerge that is resistant to all antibiotics. That would be the stuff of nightmares. If the seaweed-based antibiotic fulfils its potential, we could sleep easier as MRSAwould have met its match. But it is a killer in the here and now, which means hospitals must take every step to make sure the weaknesses it exploits are kept to the absolute minimum.

The Scottish Executive has announced measures, supported by limited funding, to improve hygiene and cleanliness in hospitals. The incidence of MRSA suggests there is room for improvement to make hospitals as dirt-free and hygienic as possible, to minimise the risk of patients acquiring infections and speed, not reverse, their recovery. That must be the priority. It is something of a paradox, which we hope will be appreciated by hospitals, that the long-term solution could still lie in a cleaning sponge.