Ten kids have shown up with a mystifying muscle weakness that may be related to an outbreak of enterovirus D68, doctors said Monday.
They said more than 4,000 children with bad respiratory illness have arrived at clinics run by Children’s Hospital Colorado since Aug. 18 — more than 10 percent above the usual rate. And they’re hearing from hospitals across the country in the same situation.
“Now we know the virus has really spread throughout the nation from coast to coast," said Dr. Christine Nyquist of Children’s.
“Roughly one in four of the patients presenting to the Children’s Colorado emergency departments has had respiratory distress,” the hospital added in a statement. It’s been hard to keep up with the volume, spokeswoman Elizabeth Whitehead said.
The Centers for Disease Control and Prevention says it’s investigating the cases of muscle weakness and has asked other doctors across the country to be on the lookout for similar symptoms. Four out of eight children showing up with the symptoms, which affect the arms, neck and sometimes muscles used in swallowing, tested positive for EV-D68. That doesn’t mean the virus caused the symptoms, and that’s what CDC wants to know.
Other viruses can also cause paralysis or muscle weakness and in the latest cases, none of the children has been actually paralyzed. Most have gone home, the Children’s doctors told a news conference.
“If this symptom is caused by EVD, it’s a very rare complication,” said Dr. Sam Dominguez of Children’s.
The doctors stress that although the virus is a distant relative of polio, well known for causing paralysis, there is no suspicion that polio is involved here and they said all the affected children had been fully immunized against polio. EV-D68 causes almost exclusively respiratory symptoms.
It’s also not clear how or why the virus would cause such symptoms. The hospital tested the spinal fluid of the 10 children and has found no evidence of any virus in there. It may attack nerves elsewhere, but that’s just a theory.
Usually, children most at risk from EV-D68 or other common cold viruses have asthma. But Nyquist says some of the children sickened in this outbreak did not have asthma, or any other condition.
“The largest majority of kids will have a runny nose."
The CDC says it has confirmed 443 cases of EV-D68 in 40 states and Washington, D.C. But that’s just the tip of the iceberg. Only the CDC and a few health departments can perform the specialized test needed to confirm enterovirus infection. Most on-the-spot tests just show a vague large category of viruses that include rhinoviruses or enteroviruses, and once doctors know a certain virus is circulating they stop testing, anyway.
Parents shouldn’t panic, the doctors stressed. “The largest majority of kids will have a runny nose,” Nyquist said. EV-D68 is one of hundreds of viruses that cause the common cold. “We just treat the symptoms,” Dominguez said.
There’s no antiviral drug that specifically treats EV-D68, although there are drugs for influenza and respiratory syncytial virus or RSV.