Lambton Public Health is still waiting to hear back from about 550 secondary students.
Supervisor Erin Courtney says if they don't update their immunization records, the kids will be suspended from school.
"They won't be allowed entrance into school on February 16 if they're not up to date or we don't have records," says Courtney. "We still are accepting records of if you child needs a vaccine please call, we still have a lot of openings for clinics."
All children, 18 years and younger, require the vaccines against diphtheria, tetanus, polio, mumps, rubella, measels, meningitis, whooping cough and chicken pox.