APPLETON, Wis. (AP) -- The Appleton Area School District is telling parents there are several confirmed cases of whooping cough in district schools.

A letter posted on the district's website says there have been several cases of pertussis at four schools: Classical, Kaleidoscope, North High School and West High School. Ferber Elementary also has been added.

Assistant Superintendent Ben Vogel tells The Post-Crescent the district is letting parents know what they can do so the illness doesn't spread further.

Whooping cough spreads through the air with face-to-face contact with a sick person.

The district's letter warns that pertussis symptoms are difficult to differentiate from a common cold, and parents should contact a physician if a child develops pertussis symptoms.

Appleton schools are not in session due to the holiday, but classes resume Tuesday.

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