ATLANTA (AP) -- A federal advisory panel wants all U.S. adults to get vaccinated against whooping cough.
The panel voted Wednesday to expand its recommendation to include all those 65 and older who haven't gotten a whooping cough shot as an adult.
Children have been vaccinated against whooping cough since the 1940s, but a vaccine for adolescents and adults was not licensed until 2005.
Since then, the Advisory Committee on Immunization Practices has gradually added groups of adults to its recommendations, including 2010 advice that it be given to elderly people who spend a lot of time around infants.
Wednesday's recommendation means now all adults should get at least one dose.
"They've been moving up to this in baby steps," said Dr. William Schaffner, a Vanderbilt University vaccines expert.
Whooping cough, or pertussis, is a highly contagious bacterial disease that in rare cases can be fatal. It leads to severe coughing that causes children to make a distinctive whooping sound as they gasp for breath.
Recommendations from the panel are usually adopted by the government, which sends the guidance out to doctors.
Contributing to the push to vaccinate more adults was a California whooping cough epidemic in 2010 that infected 9,000. Ten babies died after exposure to infected adults or older children.
There's little data on how many elderly people have gotten the vaccine. Only about 8 percent of adults under 65 have been vaccinated, but about 70 percent of adolescents have.
Health officials believe whooping cough is underreported in older adults, perhaps because in older people the illness can be hard to distinguish from other coughing ailments.
A goal of the recommendation is to prevent teens and adults from spreading the disease to infants, although there's not good evidence this "herd immunity" approach has worked so far. Vaccination for children is included in a series of shots, beginning at 2 months.
The adult vaccine combines protection against tetanus, diphtheria and whooping cough. One version of the vaccine, made by GlaxoSmithKline, was licensed for use in the elderly last year. The committee said another version, made by Sanofi Pasteur, can also be given. Both cost about $35 a dose.
The shot is as safe as a regular tetanus booster. Estimates range widely for how effective the vaccine is at preventing whooping cough in older adults, or how much its protection wanes years afterward.