MEBANE, N.C. - State health officials have confirmed a case of whooping cough at Eastern Alamance High School.

Alamance Burlington school officials learned of the case Friday afternoon and are working together to get students' parents up to speed.

"We're able to make contact with those individuals that were in those classrooms as well as those who may have been exposed to the student while riding the school bus," said Eric Nickens, Alamance County Health Dept. spokesman.

Nickens estimates as many as 100 children may have been exposed to the sick student in the last few weeks, either in the classroom or on a school bus shared with Woodlawn middle school students. The last day of school was Wednesday and employees are cleaning classrooms to disinfect.

"We've actually wiped down in the buses, so we have taken some precautions there too," said Caron Myers, Alamance Burlington Schools System spokeswoman.

The confirmed Alamance case comes as Guilford County's Health Dept. is offering free TDAP (Tetanus, Diphtheria and Pertussis) vaccination shots. The vaccine protects children from whooping cough and is mandatory for all rising sixth graders.

"It's very important that teenagers and adults get the immunization, the booster especially if there are infants and toddlers in the home because you don't know who you are exposing," said Vonda Pabon, Guilford Health Dept. nurse manager.

Myers said families of students who attend Woodlawn Middle and Eastern Alamance High schools should watch their children's health for the next few weeks.

Here is a brief explainer on whooping cough (pertussis) from the Centers from Disease Control and Prevention Web site.

Pertussis can cause serious illness in children and adults. The disease starts like the common cold, with runny nose or congestion, sneezing, and maybe mild cough or fever. But after 1–2 weeks, severe coughing begins. Children with the disease cough violently and rapidly, over and over, until the air is gone from their lungs and they're forced to inhale with a loud "whooping" sound. Pertussis is worse for very young children; more than half of infants less than 1 year of age who get the disease must be hospitalized. About 1 in 10 children with pertussis get pneumonia (lung infection), and about 1 in 50 will have convulsions.

Myers said the child with whooping cough was up to date on his vaccinations, including TDAP.

Read more about Pertussus from the CDC.gov Web site.