Health

Home Invasion

MRSA infects 94,000 Americans a year, and the superbug is no longer confined to hospitals. Here's what you need to know to protect yourself and your kids.

By: Jessica Snyder Sachs
Published: 10/2008   [ Updated: Oct 20, 2008 - 6:41:24 AM ]

It started one morning last June, when 14-year-old Max Yardley felt a little tenderness in his elbow. The arm looked fine, so Max's dad, Rockie, an explosives specialist with the Edmond, Oklahoma, police department, figured the problem was soreness left over from the lifeguard training Max had just completed. But that night, Max woke up his parents at 3 a.m. The pain had become excruciating. "This is a kid who doesn't normally complain," says Yardley. "He'd been sick all of five days in his life." The Yardleys raced to the emergency room.

Over the next 24 hours, Max's temperature soared to triple digits and his blood pressure plummeted. When doctors ran the usual laboratory tests, it came back positive for methicillin-resistant Staphylococcus aureus, or MRSA. A bacterial infection had infected the bone of Max's upper arm and was racing through his body, shredding up his lungs, liver, and spleen. "One morning we had a perfectly healthy boy. Twenty-four hours later, the doctors were struggling to keep him alive long enough for the antibiotics to start working," recalls Yardley, who, as a former paramedic, understood enough about his son's vital signs to call the family's priest.

Unknown just 15 years ago, community MRSA (hospital MRSA's virulent sister) now accounts for more than half the serious staph infections showing up in the nation's emergency rooms. Some children's hospitals see it in more than 75 percent of the staph-infected children they treat. "Once it arrives in a community, it just seems to take over," says Sheldon Kaplan, MD, chief of infectious diseases at Texas Children's Hospital, in Houston. Pediatric specialists fear that the superbug, which already accounts for 19,000 deaths in the United States each year, could soon become commonplace across the country.

The vast majority of community MRSA cases are skin and soft-tissue infections, Dr. Kaplan explains. But around 5 percent involve potentially deadly pneumonias and internal infections such as Max's. When this bug enters the bloodstream, it can cause severe and sometimes fatal disease, and many of those who survive bloodstream infections sustain severe organ damage, require limb amputation, or both. "A child's growing bones remain particularly vulnerable," says Dr. Kaplan, "because they are open to bacteria circulating in the bloodstream." Max was one of the lucky ones. After a week on a respirator, he emerged without permanent organ damage. After another two weeks on intravenous antibiotics, he finally went home to complete his recovery and was symptom free after another seven weeks on antibiotics.

Each year, more and more kids aren't so fortunate. MRSA deaths among previously healthy kids began cropping up in the 1990s. "At first we assumed these children had some connection to a health-care setting in which MRSA infections had been confined," explains epidemiologist Jeffrey Hageman, a MRSA expert with the Centers for Disease Control and Prevention, "but it eventually became clear that something else was going on." Antibiotic use outside of hospitals may have bred strains of MRSA distinct from those in medical centers. And although community MRSA isn't resistant to as many kinds of antibiotics as is hospital MRSA, what it lacks in multidrug resistance it appears to make up for in virulence.

Medical experts are just working out how staph in general, and MRSA in particular, wreaks its damage. But new studies suggest that community MRSA strains have the ability to kill the kinds of immune cells that would normally eliminate such microbial invaders. This stubborn persistence, in turn, tends to trigger septic shock, a kind of immune-system meltdown in which body-wide inflammation leads to organ failure, massive blood clotting, and plummeting blood pressure.

Community MRSA has an aggressive tendency to enter through even the smallest of cuts and abrasions. For this reason, it often spreads in locker rooms and gyms, and between members of sports and dance teams, who have frequent skin contact with both other participants' skin and shared surfaces such as athletic equipment and benches, explains Hageman. If you have a child in school or day care, chances are you've received some version of the panic-but-don't-panic note, as in "Dear parents: A confirmed case of MRSA infection has been brought to our attention. Please be assured we are taking appropriate measures." Some schools go so far as to shut their doors for a massive, one-time disinfection--a move that may be as ineffectual as it is overdramatic. A less overblown but diligent effort is key, say health experts.