Cork `bug detectives' develop quick test for dangerous hospital bacterium

A CORK research group has developed a rapid test for the potentially fatal antibiotic-resistant bacterium, MRSA, which could lead to improved treatments for patients.

MRSA is a common bacteria occurring in hospitals, where it threatens the lives of post-operative patients, the very young and old and those receiving intensive cancer therapy. It is carried on the skin and in nasal passages and is easily transferred from person to person. It has also developed a strong resistance to all but one main antibiotic group, which makes it very difficult to treat.

MRSA (methicillin-resistant staphylococcus aureus) "has been showing up in hospitals since the 1970s", according to Dr Seamus Fanning of the department of biological science at Cork RTC. Dr Fanning developed the test with Dr Bartley Cryan, consultant microbiologist at Cork University Hospital, and two student researchers, Ms Lesley Cotter and Ms Mairead Daly.

Its importance lies in how quickly the test can deliver results, said Dr Fanning. Existing tests rely on bacterial cultures and can take two days or more before a clear identification of MRSA. The new test can confirm an MRSA infection in about five hours and can also provide a genetic finger-print which helps to identify which strain of MRSA has caused the illness.

"We are trying to act as bug detectives," Dr Fanning said. The test is still under development but it can already pinpoint some of the more common MRSA strains.

The speed of the test is important in a clinical sense, Dr Cryan stated. MRSA must be identified quickly "to be able to control the source of infection and to control the spread of infection".

Single source outbreaks could be caused by a medical worker who is carrying the bacteria or by being spread by hand from one surface to another, for example in a kitchen. The test helps in locating these common "reservoirs of infection" Dr Fanning said.

The test identifies three components of the bacterium's own genetic material, which provide a "failsafe tag" confirming MRSA is present.

The MRSA test builds on research carried out on a rapid test for another bacterium, enterotoxigenic - E coli. "You are using the same technology, just changing the goal posts," Dr Fanning said.

The earlier work has already been published in the Journal of Clinical Microbiology and the British Journal of Biomedical Science.