Flu prevention is important for everyone, but here’s another reason to make sure to get vaccinated: in a study of childhood flu deaths from the 2009 H1N1 pandemic, researchers found that otherwise healthy kids can succumb to the virus, particularly if they’ve already got an increasingly common bacterial infection.
The infection, methicillin-resistant Staphylococcus aureus (MRSA), sent previously healthy kids to the hospital and increased their risk of death from flu to eight times that of MRSA-free children, according to research published Monday in Pediatrics. MRSA, which is becoming increasingly resistant to antibiotics, can cause skin infections, invade surgical wounds and wreak havoc internally.
“There’s more risk for MRSA to become invasive in the presence of flu or other viruses,” said lead researcher Dr. Adrienne Randolph of the Division of Critical Care Medicine at Children’s Hospital Boston in a statement. “These deaths in co-infected children are a warning sign.”
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The flu virus suppresses even robust immune systems, making the body more vulnerable to infection. And in children, who typically withstand exposure to massive quantities of bacteria, a dip in immunity may be the difference between a manageable bacterial colony and an invasive bacterial disease.
Randolph and her team examined the medical records of 838 children whose average age was 6; they were all admitted to intensive-care units with H1N1 flu virus during the 2009-2010 flu pandemic. Of the 75 children who died, most had at least one preexisting condition such as asthma or weakened immune systems that further compromised their ability to fight the flu. But researchers were particularly curious what contributed to the critical illnesses faced by the 251 children who were considered otherwise healthy.
They found that MRSA and its more common cousin, S. aureus, was to blame: it upped the risk of death for previously healthy kids who contracted H1N1, which is alarming because MRSA infections — though rare — are on the rise. A recent study found that more than 2% of all 2008 pediatric hospital admissions were due to MRSA — up from only .2% in 1999.
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“There’s a nice message here about vaccines: that even otherwise healthy children are still at risk, and they are at risk of death,” Dr. Lisa Saiman, a professor of clinical pediatrics at Columbia University, told The New York Times. “These findings provide further support for the recent recommendations by the C.D.C. to immunize all eligible people.”
Everyone older than 6 months should get vaccinated, recommends the Centers for Disease Control and Prevention (this year’s seasonal vaccine also guards against 2009 H1N1, which hasn’t mutated significantly since then). Roll up your sleeve — no excuses.
Meredith Melnick is a reporter at TIME. Find her on Twitter at @MeredithCM. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.