Federal health authorities said Monday they were investigating whether an unusual and sometimes severe respiratory virus, first reported this summer in Kansas City and Chicago, may be infecting children in a dozen states throughout the South and Midwest.
Enterovirus D68 has been packing the emergency rooms of Children’s Mercy Hospital, filling the intensive care unit and forcing the hospital to open additional beds. The virus, which is likely spread by coughs and sneezes, can cause wheezing and difficulty breathing, particularly among children with asthma.
Children’s Mercy reported the surge in respiratory illnesses to the federal Centers for Disease Control and Prevention on Aug. 19. Four days later, the University of Chicago Medicine Comer Children’s Hospital notified the CDC of a similar increase in cases. CDC lab tests of specimens from the two hospitals confirmed that most of the illnesses were caused by enterovirus D68 (EV-D68).
In addition to Illinois, Missouri and Kansas, nine other states — Alabama, Colorado, Georgia, Iowa, Kentucky, Michigan, Oklahoma, Ohio and Utah — are reporting unusually large numbers of respiratory illnesses, the CDC said. Testing for EV-D68 in those states in underway. The virus has been confirmed in at least one, Iowa.
“This is a very dynamic situation,” said Anne Schuchat, the director of the CDC’s center for immunization and respiratory diseases. It is difficult to say how many cases there have been, how widespread the virus will become or how long it will be around, she said.
“This can be a scary thing for parents to hear about,” Schuchat said. Parents should seek medical attention for children having trouble breathing, but “most of the runny noses out there aren’t going to turn into this.”
So far, no deaths have been attributed to the virus, Schuchat said. “Of course, that may happen,” she said.
There are more than 100 types of enteroviruses. They cause millions of illnesses each year that range from mild respiratory symptoms to fever, rash and meningitis. Infections are most common in summer and fall. EV-D68 was first identified in 1962 in California. More recently, clusters of cases have been reported in Japan and the Philippines, but it has been uncommon in the U.S.
Since Aug. 15, Children’s Mercy has tested for the virus in 646 patients with serious respiratory complaints, such as coughs and difficulty breathing. In 498 of the cases, the tests were positive, indicating that the children were infected with an enterovirus or a rhinovirus, a frequent cause of colds. Specimens are being sent to the CDC for further testing.
“We do not truly know the scope of this outbreak yet, but our suspicion is 70 to 90 percent are enterovirus 68,” said Mary Anne Jackson, the chief of infectious diseases at Children’s Mercy.
Jackson based her estimate on the results from the first batch of 22 specimens the hospital sent to CDC. Nineteen —about 86 percent — were positive for EV-D68.
Jackson said an alert emergency-room physician at the hospital was the first to realize early last month that an unusually large number of children for this time of year were coming in with respiratory symptoms. The number of cases continued to grow, peaking during the last 10 days of August. On one day, Children’s Mercy emergency rooms saw about 700 patients, several hundred more than on a typical day.
While it is too soon to say how far EV-D68 may spread, at least in the Kansas City area, there are signs the virus may be waning. About 15 to 20 patients at Children’s Mercy are being tested each day now for enteroviruses, down from about 50 to 60 a couple of weeks ago, Jackson said.
“We definitely feel it’s leveling off,” she said. “But it’s not gone.”