Two teams of experts are saying that a drug-resistant "superbug" previously only found in hospitals is becoming more common in the community and must be aggressively treated. They say that Staphylococcus aureus, or staph, infections that are resistant to methicillin and similar drugs can now be put into the category of flesh-eating bacteria and doctors need to be aware of this and exchange antibiotics at the first sign of trouble Scott Fridkin, a epidemiologist with the Centers for Disease Control and prevention, the leader of one study, says people need to be warned that if they have a staph infection that is not responding to treatment they should go back to their doctor. He says that staph causes a lot of skin infections and they are always difficult to treat but now there is a staph infection that is biologically different and resistant to first-line antibiotics. Staphylococcus aureus is usually harmless and very common, found on skin or in the noses of about 30 percent of people. It can cause stubborn problems such as boils and is often mistaken for a spider bite and until now, most of the infections caused by methicillin-resistant Staphylococcus aureus or MRSA have only shown up in hospitals. Fridkin says it appears that a surprisingly high 20 percent of such infections may have come from the community which was not the case a decade ago. Loren Miller of Harbor-UCLA Medical Center led the second study which found that some cases of flesh-eating bacteria are caused by methicillin-resistant staph and they found 14 such instances over a 15-month period, and four patients had no risk factors such as drug use, diabetes or hepatitis. Miller's team said doctors must change their attitudes toward cases of necrotizing fasciitis, the ìflesh-eatingî part of such a bacterial infection, and check to see if methicillin-resistant staph is to blame. Good hygiene, particularly hand washing, can prevent such infections. In hospitals, MRSA resists almost everything but an intravenous antibiotic called vancomycin. But so-called community-acquired MRSA can be treated with a range of antibiotics including doxycycline and cotrimoxazole, sold under the brand name Bactrim.