Less hype and more research needed into new 'superbug,' say experts

Recent tabloid hype over the "newly emerging superbug", Stenotrophomonas maltophilia, is misplaced, say experts in this week's issue of the BMJ. Headlines about S maltophilia including "no antibiotics can stop it" and "rising death toll in hospitals" are unfounded, write Georgia Duckworth and Alan Johnson, from the Health Protection Agency's Centre for Infections in London. In fact, they say, S maltophilia infections are relatively rare compared to infections caused by other species of viruses and bacteria such as Staphylococcus aureus (MRSA).

Despite recent concerns, S maltophilia accounts for less than 1% of all bloodstream infections in England and Wales. Data from the Health Protection Agency in 2007 shows that in England, 4918 cases of bloodstream infection were caused by MRSA compared with 671 by S maltophilia, while Clostridium difficle caused over 50 000 cases of gastrointestinal infections.

Indeed, S maltophilia infections are uncommon in previously healthy patients, are not easily spread, and are usually treatable, say the authors, in contrast to MRSA and C difficile which can be difficult to treat and have epidemic potential.

The authors suggest that the organism is, in reality, more deserving of the 'opportunist' rather than the 'superbug' label.

They point out that because it is relatively uncommon and treatable, it is unlikely that large scale interventions will be aimed specifically at S maltophilia, but interventions such as improved hospital hygiene and antibiotic stewardship will help prevent its spread and the emergence of multi-resistance.

"We hope that this new knowledge of the organism's biology will help allay these [recent] concerns by being used to improve diagnostic tests, identify new drug targets, or even develop a vaccine", conclude the authors.

Source: BMJ-British Medical Journal