Doctors are alarmed about soaring hospitalization rates of kids and teens in at least a dozen states across the Midwest and West. The culprit is a severe respiratory illness that’s sweeping those areas of the country just as the school season gears up, The New York Times reports.

The illness is caused by human enterovirus 68. Its symptoms mimic a very bad cold, such as fever, coughing and wheezing, with young asthma sufferers at particular risk of infection.

One pediatric clinic in Kansas City treated more than 300 children in recent weeks, and doctors placed about 15 percent of these kids in intensive care because of severe respiratory symptoms. Another hospital in Aurora, Denver, treated more than 1,400 potential cases since late August. And the largest hospital in Columbus, Ohio, says ER cases for the “respiratory syndrome” have gone up more than 25 percent over the past week.

“We’re at a stage where it’s difficult to say just how big this is, how long it will go on, and how widespread it will be,” said Anne Schuchat MD, the director of the Centers for Disease Control and Prevention’s (CDC) National Center for Immunization and Respiratory Diseases.

Currently, there is no vaccine or antiviral treatment to cure the disease.

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