A nationwide study has found that previously healthy children hospitalized with flu were significantly more likely to die if they were also infected with MRSA, or methicillin-resistant Staphylococcus aureus. The findings are important because MRSA, a severe type of staph infection, is a growing concern among healthy children.
MRSA “used to be seen only in hospitalized people or people who worked in health care facilities,” said Dr. Michael Cappello, a professor of pediatric infectious disease at Yale. “This is no longer the case.”
The study looked only at the most severe cases of flu in the United States during the 2009-10 H1N1 outbreak, children so sick they had to be hospitalized in intensive care. About 4,000 children end up in pediatric intensive care units each year because of flu, a small percentage of the millions of children who get flu each year.
“When you think about the whole population, and that pretty much everyone got the flu, for most it was a very mild illness,” said Dr. Adrienne G. Randolph, the lead author of the study and an associate professor of anesthesia at Harvard. Still, she said, “there is a risk for death, and vaccination is still the most effective prevention strategy.”
The researchers had data on 838 boys and girls under 21 admitted to 35 pediatric intensive care units across the country. Almost three-quarters of the children had one or more chronic health conditions, including asthma, immunosuppression or neurological, cardiovascular and gastrointestinal illnesses. The rest had no health problems before their hospitalization.
The median age of the children was 6 years, and 75 of them, or almost 9 percent, died. Among the deaths were 18 of the 251 children who were previously healthy.
After controlling for other factors, researchers found that being female, having a pre-existing neurologic condition or being immune-compromised increased the risk of death. Flu infections of the brain or heart and co-infection with MRSA were also predictors of mortality for all children. Almost 9 percent of the children studied were infected with Staphylococcus.
But in healthy children, only MRSA infection predicted death, and their relative risk of death was eight times as high as that of the uninfected. Of the previously healthy children who died, six were infected with MRSA and two with the more common strain of staph, S. aureus. The findings appear Monday in the journal Pediatrics.
“There’s a nice message here about vaccines: that even otherwise healthy children are still at risk, and they are at risk of death,” said Dr. Lisa Saiman, a professor of clinical pediatrics at Columbia. The Centers for Disease Control and Prevention recommends the flu vaccine for everyone over the age of 6 months, and stresses that pregnant women, children younger than 2 and people over 50 are at especially high risk of having serious flu-related complications.
“These findings provide further support for the recent recommendations by the C.D.C. to immunize all eligible people,” she said.
“Resistant organisms like MRSA are created in part by overuse of antibiotics, and treating mild infections like the common cold with antibiotics is creating more resistant organisms,” Dr. Randolph, the study author, added. “The message,” she said, is “get your kids vaccinated, and stop using all these antibiotics.”
For more on the growing threat from MRSA in children, and how to identify it, see the recent Well post “More Children Hospitalized With Skin Infections.”
