PORTLAND, Ore. – Eighteen people at Lincoln High School have been diagnosed as likely suffering from whooping cough, according to the Multnomah County Health Department.

The 18 cases are either “suspected, presumed, or confirmed,” Portland Public Schools spokesman Dave Northfield said in an email to KGW. Northfield said not many cases are confirmed because parents don’t typically have lab work done, but interviews by school nurses and Multnomah County Health officials led to the conclusion that 18 people have likely come down with the illness.

Northfield said the first case arose in April and a letter was sent to parents at that time from the health department.

There is just one more week of school left at Lincoln. The last day is Thursday, June 15.

Whooping cough, also known as pertussis, is a highly contagious respiratory disease, according to the Centers for Disease Control and Prevention. The CDC says whooping cough is generally treated with antibiotics, although some cases can lead to hospitalization.

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