MONTPELIER, Vt. (AP) -- The Vermont Health Department is urging adults to get a new vaccine for whooping cough and offering free vaccine clinics next week to prevent the spread of the contagious disease to children -- the most vulnerable -- as the state deals with an outbreak of the illness.

As of last week, 522 Vermonters -- a majority of them children ages 10-14 -- had been infected with whooping cough or pertussis this year. That's 10 times the amount reported this time last year, said Health Commissioner Dr. Harry Chen.

"These are epidemic numbers for our small state," said Chen, who said more cases of the disease are being reported daily from every county.

Vermont is not alone. Other states are seeing big numbers, he said.

A major concern is that 23 babies under age 1 who are too young to be fully protected by the vaccine and at the greatest risk of death from the disease have been infected in Vermont, Chen said. Six infants were hospitalized, he said.

"Despite our best collective efforts, whooping cough is spreading throughout the state. That's because it's a highly contagious bacterial infection that's easily spread from person to person from simple things like coughing, sneezing and even talking to one another," Chen said.