Close to 2,600 area students are facing suspension from school early next year.
Lambton Public Health's Erin Courtney said they're sending out notices to parents with children in elementary school and high school. She said they need to update their child's immunization records or provide proof of exemption.
"It's a great number, we're down over 800 letters from last year," said Courtney. "We are hearing more from parents, whether it be they're dropping in or e-mailing them or calling in. Health care providers are also the parents to do that as well, to report to us, so we are seeing a decrease and it's great."
Courtney said letters are also being sent to just over 300 parents with children in a licensed daycare.
Lambton Public Health said the records include immunizations for diphtheria, tetanus, polio, mumps, rubella, measles, meningitis, whooping cough and chicken pox for children born in 2010 or later.
If an update is not provided by January 11, 2019, the child faces suspension as of March 4, 2019.