Hundreds of children got an unscheduled day off school this week after 659 elementary students in the Windsor, Ont., area were suspended for having incomplete immunization records.

The Windsor-Essex County Health Unit ordered the suspensions Thursday after reviewing health records of children at several boards in the community. The suspensions affected those born between 2008 and 2011 and could last up to 20 days.

The mass suspensions meant that parents and children were lined up outside the health unit on Thursday morning looking to get their missing shots or delivery the proper paperwork.

“It’s very busy. Lots of people coming to bring in their children’s records, to have their kids immunized, faxes from physicians we’re receiving,” Judy Allen, manager of the health unit’s Healthy Schools team, told CTV Windsor.

“It’s been a line out the door pretty much all morning.”

Some parents said they were surprised to learn that their kids were suspended, because they had all the necessary shots years ago.

“She is immunized,” said one mother of her daughter. “She’s fully up to date on all her immunizations. But apparently they didn’t have the records. So they didn’t give us the opportunity to provide that record prior to suspension.”

The health unit said letters were sent out in April and again in June warning parents about their children’s incomplete records. On Sept. 1, the board sent out another round of approximately 2,300 letters alerting parents of the imminent suspension on Sept. 28.

One mother said she didn’t think twice when she got the notice. “I honestly didn’t think anything of it because (the health unit had) my records when I registered my son. So where did these records go?”

The health unit said that many parents don’t realize that, when their child is immunized at the doctor’s office, physicians aren’t required to provide those records to the health unit, which keeps track of the information and can ask boards to issue suspensions.

“It’s very common for parents to think that physicians automatically give us the records, and that’s not the case,” Allen said.

The health unit said it’s up to parents of suspended children to contact them online, in person or by phone. After immunization records are updated, a letter will be issued to the student allowing them back into class.

Students must be immunized against meningococcal, measles, mumps, rubella, diphtheria, tetanus, pertussis, polio and varicella to attend school.

If parents don’t want to immunize their children, they must receive a formal exemption from health authorities.

As for the suspended kids, their responses were mixed about getting a surprise day off.

“I feel awkward about it because, well, I’m not sick,” one girl said.

Another student shrugged off the question and smiled, saying she felt “not that bad.”

With files from CTV Windsor