BURLINGTON — Vermont health officials are urging adults to get a new vaccine for whooping cough as the state deals with an outbreak of the disease.

More than 500 people have been affected by whooping cough or pertussis this year. That’s 10 times the amount reported by the end of 2011.

More than 20 babies younger than a year have had the disease and six infants have had to be hospitalized.

The Health Department is recommending that anyone over 19 get a Tdap vaccine, which is a booster against tetanus, diphtheria and pertussis, to help prevent the spread of the disease.

The Health Department will be holding free vaccination clinics next Wednesday at its 12 local district offices around the state for Vermonters who can’t get to their doctor for a shot.