WILMETTE (CBS/STMW) — An outbreak of whooping cough at a north suburban middle school in September and October appears to have ended with 13 cases reported.

No case of the highly contagious bacterial infection, known medically as pertussis, has been reported in any other District 39 school, Superintendent Ray Lechner said Wednesday.

Lechner said the first three cases were reported at Highcrest Middle School in September, and the district notified the Cook County Department of Public Health, as is required by law after three or more cases are identified. The other 10 cases were reported in October.

Parents of  Highcrest fifth-grade students who were at risk through exposure to the original cases were the first to get letters alerting them to the situation, Lechner said. When the district decided to hold a booster vaccination clinic, parents of fifth- and sixth-graders were told about the opportunity, he said.

Parents in other schools weren’t notified of the whooping cough cases, he said, because they were contained in those grade levels.

Cook County ran the free booster clinic and provided the vaccine, when the clinic was held Oct.27.

Highcrest nurse Pam Strunk said Thursday that the county clinic had provided 300 doses of pertussis vaccine, and that 84 students were vaccinated; 80 were fifth-graders, while four were in sixth grade.

Strunk said roughly 20 percent of the fifth-grade class took advantage of the clinic, “but we know that several families contacted their own pediatricians about vaccines,” she said.

Strunk and Lechner both said the cluster of cases at Highcrest could probably be traced to a change in vaccination reporting mandates.

Students’ families used to be alerted to the need for pertussis booster shots at the fifth-grade level. That requirement has been moved to the sixth grade, “and most of our sixth-graders have already had their booster shot,” Lechner said, “so there was just this window at the fifth-grade level.

No whooping cough case has been reported in nearby Kenilworth School District 38.

In Wilmette, CBS 2’s Suzanne Le Mignot reports, there have been six cases of whooping cough at Carleton Washburne School.

“The teachers were noticing a lot of students with a heavy cough, a constant cough and they were being sent to the nurse,” principal Cathy Rosen said. “She followed up immediately and noticed there was a pattern here.”

Dr. Kenneth Fox, a pediatrician, says because most kids get five doses before kindergarten, protection doesn’t last a lifetime. Most kids are susceptible again by middle school age.

“Vaccines are really safe, and this one in particular is very effective at preventing the illness,” Fox says. “We think they’re a good idea for kids. But they’re not 100 per cent effective.”

(Source: Sun-Times Media Wire © Chicago Sun-Times 2010. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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