— OKLAHOMA CITY (AP) – The demand for whooping cough vaccinations has sharply increased, Oklahoma health officials said Friday, spurred on by word of a possible epidemic of the highly contagious disease, as well as a 2011 state law mandating immunizations for public school students.

Nearly 18,000 cases have been reported nationwide – more than twice the number seen at this point last year, the Centers for Disease Control and Prevention said Thursday. At this pace, there could be the highest number of cases since 1959, when 40,000 illnesses were reported.

In Oklahoma, however, there have been just 28 confirmed cases and no deaths this year. That’s down from 38 at this time last year, when there were a total of 69 cases of whooping cough, or pertussis, said Bobbie Nubine, the chief of immunization services at the Oklahoma Department of Health.

But that hasn’t kept people from seeking vaccinations for tuberculosis, diphtheria and pertussis, or Tdap.

“We’re out of vaccine in Altus, we ran out here. Word got around and we ran out here,” said Karen Weaver, the director of six county health agencies in western Oklahoma.

“In Beckham County, in July, we provided about 386 doses. We usually have about 40, 50 doses,” Weaver said.

She attributed the increase in vaccinations to media reports, both in traditional news sources and on social media, about the large number of whooping cough cases in other states, particularly Washington and Wisconsin, which have each reported more than 3,000 cases.

“Several people have told me they’ve seen it on Facebook,” Weaver said.

Nubine said immunizations are recommended for children at 2, 4 and 6 months of age and are required before they enter kindergarten in Oklahoma. A state law approved last year requires public school students to receive a booster shot of Tdap.

“We have a mandated requirement for seventh-graders, to enter Oklahoma schools you have to have a booster starting with 2011-2012 school year,” Nubine said.

At the Oklahoma City-County Health Department, there was no shortage of the vaccine, but a large demand for it, said spokeswoman Vicki Monks.

“Our waiting room is packed, but that’s kind of normal in the back-to-school rush,” she said. “A lot of parents realize right now, just before school starts, ‘Oops, I’ve got to get this done.’ “

Health officials have called on adults, especially pregnant women and those who spend time around children, to get a booster shot as soon as possible.

“It is a vaccine-preventable disease,” Nubine said. “If you’re an adult and you have a cough you don’t want to be around any children.”