An increase in the incidents of whooping cough has Tompkins County residents concerned. 

Nine of the 21 confirmed cases reported through the county's health department this year came in November alone. 

Doctors say unvaccinated adults are often carriers that spread the bacteria to children.

"The adults may have mild symptoms which will look like cold symptoms and they may have the minimal cough and it'll go away,” said Syed Shah, a physician with Guthrie Medical Group.  “But during those mild symptoms that they might have and they would recover easily, they could pass on that bacteria to the younger folks."

Experts say people experiencing a persistent cough after their cold subsides, should see their doctor as soon as possible.