Reassurance a tough sell after fatal staph infections

Gerberding tries to allay fears about CA-MRSA

In the aftermath of highly publicized cases of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) that claimed the lives of at least three school children and rattled parents nationwide, Julie Gerberding, MD, MPH, director of the Centers for Disease Control and Prevention, recently sat before concerned members of Congress, urging calm and common sense against a "preventable" infection.

It was a tough sell, one made all the harder by recent prevalence surveys and incidence studies that suggest that MRSA is endemic in hospitals and increasing in the community to the somber tune of more than 18,000 overall deaths a year. Though unflappable as usual, Gerberding faced the difficult balancing act of allaying fears without minimizing the threat of CA-MRSA in the wake of the fatal infections. She emphasized there is no need to shut down entire schools if a student gets CA-MRSA, but recommended targeted environmental cleaning, avoiding sharing of objects such as towels, frequent hand washing, and mindful care and covering of wounds.

"We believe there's a lot we can do in the community. We have to get back to basics," she told the House Committee on Oversight and Government Reform at a Nov. 7 hearing. "We estimate that about 200 children [annually] will get a serious MRSA infection, [but] even those who get the bloodstream form of this — the vast majority of them will be treated and survive. So we are not talking about thousands and thousands of kids but we are talking about some children, and we have to take each one of these children to heart and try to do the prevention steps that will help."

The predominant USA300 strain spreading in the community usually causes only minor, treatable skin and soft-tissue infections, she added. "Serious invasive disease, like we are hearing about in the news this week, is fortunately extremely rare, but it is tragic and it is preventable," Gerberding said. "When you look at it overall, it does represent a serious threat. Generally these infections occur in healthy people, so you don't have to be debilitated or have a chronic disease. They tend to sometimes occur in athletes that share athletic equipment and are injured with turf burns, cuts, and scrapes."

Despite the message of reassurance, committee chairman Henry Waxman (D-CA) was troubled by the aforementioned mortality study and its additional findings that there are some 94,000 invasive MRSA infections annually.1 "When you hear a figure like that, it sounds pretty serious," he said. "It's not the kind of thing you are describing as being routine."

Gerberding said the majority of the infections in the study were health care-associated — not the community infections the hearing was called to address. In that regard, she noted that hospitals are showing dramatic results in reducing MRSA infections by emphasizing measures such as prompt removal of catheters before they can seed a bloodstream infection.

"We have proven beyond the shadow of a doubt that you can drive staph infections down to a minimum — particularly the invasive ones caused by catheters that infect the bloodstream," Gerberding said. ". . . In fact, we have some evidence that probably the number of these [MRSA] infections in hospitals is going down because of the emphasis on improving safety in hospitals and preventing some of the underlying causes of these infections. [But] this study sent an alarm. It is a big problem we need to address aggressively, but the piece of it [that is CA-MRSA] is a small proportion of that 94,000 [infections]."

Though her general message reflected her role as a public health leader charged with reassuring a panicky public, Gerberding did not minimize the tremendous challenges posed by a ubiquitous, resourceful microorganism. "This problem [of CA-MRSA] is not as new as it seems from the news," she said. "It is a problem that actually has been going on for more than a decade. But we are grateful for this chance to shine this bright light on it and think through what else we can do to help prevent such tragic deaths."

Comparing bug to bug

And what is revealed by that bright light? Something that is everywhere and everywhere unwelcome, Staph aureus, the "cockroach of bacteria," as she called it. "I know this organism and it is a bad bug," Gerberding said. ". . .They are survivors, they last a long time on surfaces; it is just about impossible to get rid of them."

Reminding the panel that staph has been showing the ability to resist antibiotics since the penicillin era, Gerberding said, "these organisms evolve resistance much faster than we can evolve immunity or new drugs to combat them. They will always be one step ahead of our drug store. If we use the antibiotics, we eventually lose their effectiveness and so the overarching lesson here is that we have got to be more prudent in our use of antibiotics and only use them when they are absolutely essential."

Gerberding said currently some 1 million people in the United States are carriers of MRSA. "In 2001-2002, only a small proportion of our population was carrying the methicillin-resistant Staph," she said. "And it's only gone up to be about 1.5% [colonized]. But that is an increase, and it's a statistically important increase and it represents more than a million people. So we do have this organism colonizing people's noses everywhere around our country every day."

That million goes up to 100 million if you include the number of people who at any given time are colonized with some strain of staph. "Staph aureus is everywhere. We have gone across the United States and screened people's noses for staph. About a third of the people in our country at any given time have Staph aureus in their nose. So if you look to the right and look to the left [to the person next to you], one of the three of you have a good chance of being a carrier of Staph aureus at least at this moment in time. It is an everywhere organism and it is not the kind of thing we are going to completely eliminate," Gerberding said.

Returning to the recent fatal infections in children, Gerberding urged the committee to support efforts to hire more school nurses. "In our country today," she says, "only about a third of schools have a full-time school nurse. . . . Our schools simply don't have the access to the health professionals they need to recognize the prevention tools and take the steps necessary to protect our children from this or any other health threat that could be emerging."

Reference

  1. Klevens RM, Morrian MA, Nadle J. Invasive methicillin-resistant Staphylococcus aureus infections in the United States. JAMA 2007; 298:1,763-1,771.