The recent publication of the genome sequence of the bacterium Stenotrophomonas maltophilia was accompanied by a press statement that described this organism as a “newly emerging superbug.”1 2 This was followed by a flurry of headlines in the United Kingdom informing the public of problems related to S maltophilia, such as the apparent “rising death toll fear in hospitals” (Daily Mirror) and the concern of doctors that “no antibiotics can stop it” (the Sun). Suddenly, the public had a new superbug (or even “mega-bug”, as it was referred to in the Sun) to worry about.

So, what must a bacterium do to earn “superbug” status? One prerequisite is resistance to multiple antibiotics and the associated difficulty in treating infections. Using this criterion, S maltophilia is a strong candidate because it is inherently resistant to a wide range of antibiotics …