It turns out that enterovirus D68, which sent about 500 children to Children’s Mercy Hospital last fall and sickened hundreds of others across North America, is no deadlier than other common cold germs.
A study published this week in the Canadian Medical Association Journal (CMAJ) says that while the virus was particularly aggressive and spread quickly, children with EV-D68 didn’t have a greater risk of death than kids who caught other viruses.
EV-D68 can cause difficulty breathing and mimic an asthma attack. Most affected patients will display symptoms of the common cold but some will develop more severe symptoms requiring medical attention.
At its peak about a year ago, Children’s Mercy was seeing 30 patients a day.
The CMAJ study compared 87 kids treated at McMaster Children’s Hospital in Ontario, Canada, with 87 kids who came down with other viruses at around the same time.
Its findings match up with those of Children’s Mercy researchers, who, in a paper published recently in the Journal of Clinical Virology, found that the mortality rate and the length of hospital stays were about the same for groups of kids with EV-D68 and groups of kids with other enteroviruses or rhinoviruses.
However, the Children’s Mercy study also found that children with a history of asthma or recurrent wheezing were more likely to be admitted to the ICU.
“Which is not incredibly surprising,” says Dr. Jennifer E. Schuster, an infectious disease specialist at Children’s Mercy lead author of the paper. “A lot of these respiratory viruses hit asthmatics the hardest.”
“And interestingly, older children were more likely to be admitted to the ICU, which goes against what we’ve seen in the past,” she says.
Why that’s so, she says, remains a mystery.
Schuster says the median age of kids in Children’s Mercy’s pediatric intensive care unit was 7 compared with 4 ½ for kids not in the PICU.
“Usually, what we’ve seen with other respiratory viruses, it’s infants and occasionally toddlers who require ICU care. But in the EV-D68 kids, it was school-age kids, which is really unusual,” she says.
One other unresolved mystery is the link, if any, between EV-D68 and a mysterious neurologic condition known as acute flaccid myelitis (AFM), which causes a sudden onset of weakness in one or more arms or legs.
Three patients at Children’s Mercy developed the condition between mid-September and October of last year – about the same time the hospital was seeing lots of EV-D68 patients.
“Timewise, there seems there is some sort of link,” Schuster says. “Unfortunately, proving that is much more difficult.”
Dan Margolies, editor of the Heartland Health Monitor team, is based at KCUR. You can reach him on Twitter @DanMargolies.