Health officials in Washington state are alerting residents to a sharp rise in cases of pertussis, also known as whooping cough, and medical experts are putting part of the blame on a lack of vaccinations.

"Part of it is vaccination rates are waning in pertussis and this is a natural cycle of the disease," said Dr. Scott Lindquist, the state Medical Epidemiologist at the Washington State Dept. of Health.

As of November 2, the CDC shows nearly 2,000 cases reported in the state. Some two dozen people have been hospitalized including at least 12 infants. There were only 51 cases reported at this time last year.

Dr. Beth Ebel, a UW professor of medicine and a pediatrician at Seattle's Harborview Medical Center, says that infants are especially susceptible to negative impacts of whooping cough because of their small airways.

"Whooping cough typically starts with cold symptoms and fever and a cough, but little kids can present very differently. They can present with difficulties breathing and basically apnea or turning blue, problems like that," said Dr. Ebel.

She says the complications for small children go far beyond a cough and can be very serious.

"Apnea, or basically problems remembering to breathe, and pneumonia and even seizures and brain infections are all part of what makes it such a scary, serious disease," she said.

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Whooping cough is spread through cough or sneeze droplets. Symptoms can seem like a common cold, beginning with a runny nose and a sore throat. But it can turn into a prolonged cough. Someone can be contagious with whooping cough for three weeks.

"If that cough is lasting more than what a usual virus lasts, a couple of days up to a week, then you should get tested for pertussis," said Dr. Linquist.

Nationally there are more than 22,000 cases of whooping cough, compared to just 4,800 at the same time last year. Cases used to be frequent until a vaccination was developed in the 1950s.

"Kids need to get vaccinated. These are effective vaccines. They work incredibly well. We can start giving that vaccine to little babies as soon as two months of age," said Dr. Ebel.

Dr. Ebel says as vaccination rates are down, she welcomes questions from parents who may have concerns about vaccines.

"Most all of the time when we have a conversation about the pertussis vaccine and these, longstanding, very effective vaccines, when families know this is one of the easiest, simplest things they can do to keep their kids safe, they are very on board with getting vaccinated and getting the family vaccinated," she said.

Dr. Ebel recommends pregnant moms get the vaccine in their last trimester for added protection for baby.

"This is fantastic because kids can't get this vaccine until they're two months old, but when mom gets that vaccine, she is making that antibody protection for the baby.

And that is hugely, hugely helpful," she said.

The CDC reports another respiratory illness is also on the rise. Walking pneumonia infections, especially among young children, began increasing in late spring, peaking in late August.

And the increase is coming as flu season is set to begin its peak period next month.

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