— A confirmed case of pertussis, more commonly known as whooping cough, has made its way into Zionsville schools.

the case was found in a juvenile student at Zionsville Community High School.

according to Bob Bostwick, Zionsville Community Schools executive director of human resources and operations, the case was confirmed Wednesday, Jan. 16, from a physician who reported it to the Boone County Health Department.

“we took steps to immediately notify parents of all medically fragile students and any students who have not received the pertussis vaccination due to medical or religious grounds,” Bostwick said. “we also heightened our efforts to disinfect common areas. It is important for parents and school personnel to be as vigilant and proactive as possible in combating all communicable health conditions.”

A letter was sent home with students on Feb. 16 that let parents know a case was identified in the school and exposure to some students may have occurred either in the classroom or on the bus.

Indianahas a state law that requires students starting school to provide proof that they are up to date on their immunizations for whooping cough as well as polio, diphtheria, tetanus, measles, mumps, rubella, hepatitis B and chickenpox, or show evidence they’ve had chickenpox.

A new state law also required by January vaccinations against meningitis, a second chickenpox shot and an updated shot inoculating children against whooping cough, diphtheria and tetanus.

Exemptions are granted only for religious or medical reasons.

Cindy Murphy, head of the nursing and vital records division of the Boone County Health Department, said the immunization to protect against pertussis is not 100 percent effective.

“It is possible for students to get whooping cough even though they have been vaccinated,” Murphy said. “Unfortunately, we are seeing cases in folks updated with their immunizations, although it’s not common.”

the infected Zionsville student had been vaccinated.

Murphy said the vaccine is still being studied by the Centers for Disease Control to see why there are still cases of pertussis even with vaccinations.

“we encourage people to get vaccinated, but it’s not giving people the 100 percent protection we wish it could,” she said.

according to the Indiana State Department of Health, symptoms usually begin in 7 to 10 days following exposure, which can be spread by contact with nose or throat secretions from an infected person; symptoms last four to 21 days the first symptoms of pertussis are those of the common cold with a mild cough. after a week or two, the cough becomes more severe and may occur more frequently during sleep.

As the cough gets worse, it usually includes a series of coughs, such as coughing fits or spasms. People with pertussis may have vomiting following the coughing spell and have difficulty catching their breath, which may cause a whooping sound. However, adolescents, adults and very young infants may not develop the whoop. Generally, there is no fever with pertussis.

State health officials say Indiana is on track for the highest number of pertussis infections since 1986, mirroring a national trend in the escalation of the highly contagious respiratory disease.

Health experts say the rise in reported cases may be due in part to better diagnostic testing.

But they also point to the number of children who may not have been vaccinated against the disease as well as the number of teenagers and adults who failed to get the booster shots designed to keep their immunity from waning.

“Infants are the most vulnerable and they can die from the disease,” said Dr. John Christenson, director of pediatric infectious disease at Riley Hospital for Children in Indianapolis. “But teenagers and adults serve as the vectors for the disease, transmitting it to infants who have no immunity.”

Statehouse bureau chief Maureen Hayden contributed to this story