A new study shows that Methicillin-resistant Staphylococcus aureus (MRSA) may trick and destroy immune system cells when they are vulnerable. The research, published in the journal Nature Medicine, found that some strains on MRSA secrete a compound called phenol-soluble modulin (PSM). This substance attracts immune system cells called neutrophils and then destroys them in a process called lysis.

"This elegant work helps reveal the complex strategy that S. aureus has developed to evade our normal immune defenses," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said in a statement.

"Understanding what makes the infections caused by these new strains so severe and developing new drugs to treat them are urgent public health priorities."

There are two main types of MRSA. The hospital-acquired MRSA, which is responsible for nosocomial infections, is much more dangerous because it is resistant to most antibiotics. The community-acquired MRSA usually is caused in the United States by a strain designated ST8:USA300. This type of infection is more virulent but a lot easier to treat, and in many cases antibiotics are not required.

"Here we describe a class of secreted staphylococcal peptides that have a remarkable ability to recruit, activate and subsequently lyse human neutrophils, thus eliminating the main cellular defense against S. aureus infection," the researchers wrote.

Paranoia was unleashed after this October researchers reported that MRSA was responsible for 94,000 hospitalizations and may have contributed to 19,000 deaths in 2005 in the United States. These figures were distorted by the media and interpreted as if the 19,000 deaths were caused by the MRSA, which is false. MRSA was found in 19,000 people who died, but the vast majority of those had other primary, lethal diseases.

There are antibiotics which kill of most nosocomial MRSA infections, but they are used only as a last resort as otherwise resistant strains would pop up everywhere. In fact, a MRSA dubbed vancomycin intermediate-resistant Staphylococcus aureus (VISA) has appeared, which is resistant to the powerful vancomycin antibiotic. In 2006, Merck reported in Nature that they discovered an entirely new type of antibiotic, called platensimycin, which is allegedly very successful against MRSA.