A key reason why a powerful strain of drug-resistant staph infections known as MRSA has proven so deadly is because it produces a compound that causes immune cells to explode, a new study in Nature concludes. The finding helps explain why MRSA, usually found in hospitals in patients with weakened immune systems, has also recently caused fatal infections in otherwise healthy people.
Both what's called "hospital-associated" and "community-associated" MRSA contain genes for the peptides, researchers found, but they were much more common in the latter. "Specifically identifying a factor which seemingly makes CA-MRSA more pathogenic than HA-MRSA is a real find," said one biologist. The information will be critical as researchers develop new vaccines and treatments. (Read more MRSA stories.)