COLUMBIA -- A drop in S.C. childhood immunizations and a recent spike in cases of whooping cough statewide -- a potentially fatal disease -- has public health officials and lawmakers working to ensure children are vaccinated against that disease.

Starting in the fall, the state will require all rising seventh graders to prove they have received a vaccine for pertussis, or whooping cough, on or after their seventh birthday. The vaccine also includes immunizations for tetanus and diphtheria.

Whooping cough is a highly contagious, potentially fatal respiratory disease that is most severe in infants. It can prevent an infant from breathing or eating, and can cause brain damage, pneumonia and other serious conditions.

The disease often is transmitted to infants from adolescents and adults who carry it, said Leanne Bailey, director of S.C. Department of Health and Environmental Control's immunization division. Ensuring adolescents are immunized is an effort to curb future cases, especially among infants, Bailey said.

Legislators are concerned about falling vaccination rates.

"If we stay on this course, some diseases we thought were near eradication could resurface," said state Sen. Brad Hutto, D-Orangeburg, a member of the Joint Citizens and Legislative Committee on Children, made up of legislators, citizens, and public health and education officials.

Legislators are moving to make mandatory an immunization-reporting system that health care providers now participate in on a voluntary basis. When the program begins, the state will have more reliable data about how many children are getting immunizations, Bailey said.

The registry also will help doctors diagnose patients more accurately and quickly, said Anna-Kathryn Rye, director of the Division of Pediatric Infectious Diseases at the University of South Carolina. Asking parents about their children's vaccine status is not always accurate because, "most of the time, parents have no idea," she said.