A respiratory illness that has hospitalized children in 12 states is quite likely on its way to becoming a nationwide problem. Doctors suspect the virus is the rare and highly contagious respiratory virus called enterovirus D68. And while the disease has not been officially named, the U.S. Centers for Disease Control and Prevention says the virus is related to the rhinovirus which causes the common cold.

The director of the Division of Viral Diseases at the CDC says cases have been reported in Alabama, Missouri, Kansas, Georgia, Illinois, Kentucky, Iowa, Colorado, Ohio, Oklahoma, North Carolina, and Utah. The illness appears similar to a severe cold, but it can be particularly dangerous to children with asthma because of how it affects the respiratory system. Hundreds of cases have been reported in children from six weeks old to 16 years old.

With children across the country returning to classes after summer break, the CDC is reminding parents of ways to keep their children healthy by recommending basic sanitary practices to avoid spreading the virus, including: washing hands, avoiding those who are sick, and covering the nose and mouth during sneezes or coughs.