With the continued rise of whooping cough locally and around the state, public health officials have a simple message for kids and adults: Get immunized.
As of July 31, 450 cases had been reported in Montana for the first half of the year, compared with 549 cases in all of 2012.
Richard Opper, director of the state Department of Public Health and Human Services, has urged parents to make sure their children’s immunizations are current.
“School will be back in session soon, which means kids will be around each other for longer periods of time and germs can spread more easily,” Opper said. “A majority of cases this year involved school-age children who were not up to date on their pertussis vaccination.”
Yellowstone County this year ranks third in the state for whooping cough, with 36 cases as of July 29. But statistics don’t paint the whole picture, said John Felton, CEO and president of RiverStone Health and Yellowstone County health officer.
“The bigger numbers we’re seeing now are a fraction of the total prevalence of the disease,” Felton said Wednesday.
That’s because adults tend to experience milder cases of whooping cough, or pertussis, with coldlike symptoms and a lingering cough. The patient may not see a doctor, or the doctor might not order a definitive test because of the cost, and the case is not reported.
The time between exposure to whooping cough and when symptoms develop can vary from a week to 21 days, said Kim Bailey, communicable disease public health nurse with RiverStone. And people can be contagious for another 21 days.
So it’s easy to spread the illness from one person to the next.
“If somebody’s diagnosed, those people need to be on medication for five days before they can return to work, day care or school,” Bailey said.
The problem, said Dr. Jason Price, a RiverStone physician, is that whooping cough hits the most vulnerable patients, babies, the hardest.
In 2012, the Centers for Disease Control and Prevention (CDC) reported 41,000 lab-confirmed cases, Price said.
“There were 18 deaths, so people do die of pertussis, and almost all of those were kids under 3,” he said.
Babies can experience symptoms that include coughing, apnea, in which they stop breathing, and low oxygen levels. In severe cases, they are hospitalized on oxygen.
Reasons for the resurgence in the disease may not be fully known, Price said. But they likely include better diagnosis, better tests and the fact that the effects of immunization begin to wane soon after they’re given and are gone completely after probably 10 years.
“If you get a series (of vaccinations) as a kid, by the time you’re 15, 20, 30, 40, 50 and have grandkids, you may not have any immunization at all,” he said.
Before an immunization to whooping cough was developed, nearly all patients with pertussis were children, with only 10 percent adults, Price said. Now, the number of patients is split almost evenly between children and adults.
“So we have a reservoir of adults who don’t have immunizations and, with kids who are not immunized, adults can pass it onto the kids,” he said.
Typically, children get a series of five immunizations from the time they are 2 months until they are in middle school. The vaccine protects against pertussis, diphtheria and tetanus.
But because the protection against pertussis gradually lessens and then goes away, adults need to get a booster shot. The protection is as much for the infants, who are not fully protected, as it is for the adults, Bailey said.
As of this year, the CDC is now recommending that every pregnant woman gets what’s called a Tdap booster, Price said, which protects against pertussis. In that way, the antibodies from the mother can be passed on to the baby.
“It’s not 100 percent, but then newborns and infants have some protection,” he said.
The booster is given to a mother for each pregnancy, Price said. The Tdap booster, which came out in 2005 and only recently became available to adults, is available without a doctor’s appointment at RiverStone Health.