Hospitals across 10 states have reported a rising number of cases of a rare respiratory infection among children, following last week's alarm raised by medical facilities in Illinois and Missouri. Officials from the Children's Hospital Colorado said that they have so far treated more than 900 children since Aug. 18 and have admitted 86 children with the infection.

States including Colorado, North Carolina, Georgia, Ohio, Iowa, Illinois, Missouri, Kansas, Oklahoma and Kentucky have contacted the Centers for Disease Control and Prevention's viral diseases division for assistance in investigating the enterovirus. Mark Pallansch, director of CDC and a virologist, reportedly said that the number of detected cases could be the "tip of the iceberg." There is no specific treatment or medication yet to tackle the virus, suspected to be the enterovirus EV-D68.

“We're in the middle of looking into this," Pallansch told CNN on Sunday, adding: "We don't have all the answers yet."

While enteroviruses are common and usually reach a peak rate of infection during September, the EV-D68, which was first identified in the 1960s is rarer and has been known to be fatal in some cases, CNN reported. Symptoms include coughing and difficulty in breathing, as well as fever and wheezing in some cases.

Raju Meyappan, a pediatric critical-care physician at Denver’s Rocky Mountain Hospital for Children, said, according to Denver Post: "They seem to have an abrupt onset and extremely severe reaction to this virus," adding: "Keep the albuterol handy. But even with all the right therapy this can happen very, very rapidly."

At Children's Mercy Hospital in Kansas City, nearly 475 children have been treated for the infection and 60 have received intensive care. At Blessing Hospital in Quincy, Illinois, more than 70 children were reportedly admitted with the viral infection. Hospitals in these cities have barred the entry of healthy children into their facilities.