Hundreds of children in more than 10 US states have been sickened by a severe respiratory illness that public health officials say may be caused by an uncommon virus similar to the germ that causes the common cold.
Nearly 500 children have been treated at one hospital alone -- Children's Mercy in Kansas City, Missouri -- and some required intensive care, according to authorities.
The suspected germ, enterovirus 68, is an uncommon strain of a very common family of viruses that typically hit from summertime through autumn.
The virus can cause mild coldlike symptoms including runny noses, coughing and wheezing but Mark Pallansch, director of the viral diseases division at the federal Centres for Disease Control and Prevention, said this summer's cases are unusually severe and include serious breathing problems.
"It's not highly unusual but we're trying to understand what happened this year in terms of these noticeable and much larger clusters of severe respiratory disease," Pallansch said yesterday.
The virus typically causes illness lasting about a week and most children recover with no lasting problems.
Authorities in Illinois and Colorado said their states are among those with suspected or confirmed cases. A CDC spokesman said the agency also is testing to see if the virus caused respiratory illnesses reported in children in Alabama, Georgia, Iowa, Kansas, Kentucky, Ohio, Oklahoma and Utah.
The CDC's Dr Anne Schuchat said at a news briefing yesterday that there are other viruses making kids sick.
"Most of the runny noses out there are not going to be turning into this," she said.
Children with asthma and other health problems are especially at risk for the entervirus, but reported cases include children without asthma who have developed asthmalike breathing problems, Pallansch said. He said no deaths have been reported in the outbreak.
Dr Mary Anne Jackson, director of infectious diseases at Children's Mercy, said local cases began appearing in mid-August and they appear to have peaked in her area.
Schuchat, said the strain involved also appeared in the United States last year and in specimens from other countries.
She said the CDC learned it had reappeared in this country last month when authorities in Chicago and Kansas City notified the agency about severe illnesses in children who had to be hospitalised.
