An Edmonton elementary school student with diphtheria has exposed a small group of people to the potentially life-threatening bacterial infection.

Alberta Health Services confirmed the case on Friday and is contacting individuals who may have had close contact with the student.

"At this time, no other cases have been identified and the risk to the public remains extremely low," spokesperson Kerry Williamson wrote in an email to CBC News Monday.

"AHS encourages parents and guardians to ensure they and their children are up to date on their immunizations."

Seven students in affected classroom

Lisa Connolly, whose son attends Evansdale Elementary School in north Edmonton, said an unknown telephone number flashed onto her phone Saturday.

She accepted the call, confused when a man identified himself as an AHS worker.

Lisa Connolly says her son, Jessy Connolly, is not allowed to be near other children until AHS can confirm he did not catch diphtheria from a classmate. (Lisa Connolly)

Confusion turned to shock as he explained a student in her son's Grade 5 special-education class had been diagnosed with diphtheria.

Her 10-year-old son, Jessy, is immunized but Connolly said she learned there is a small chance he could still become sick.

"I started crying and was angry," she said. "Diphtheria is serious.

"It's not a cold, it's not a cough, it's not a rash — it's a life-threatening disease that we shouldn't have our children exposed to in this day and age."

There are seven students in her son's class, Connolly said. She was told AHS needed to test the children for diphtheria as a precaution.

Within hours of the call, another AHS worker arrived at Connolly's home in the Kensington neighbourhood.

"She got out of her vehicle and put on a special suit," Connolly recalled.

The woman also pulled on gloves and a protective face mask before approaching the house.

"It's scary because you're watching this person put all their stuff on," Connolly said. "If it's not so serious, why are you putting all this stuff on?"

After swabbing Jessy's nose and throat, the woman checked under his clothing for sores.

Until Jessy's test results come back clear, his mother said he is not allowed to be near other children. In the meantime, AHS staff are calling every day to ask if he has developed symptoms.

'I just had a fear of him dying'

After the AHS worker left, Connolly said she researched diphtheria online. What she found terrified her.

"Even though my child is vaccinated, I just had a fear of him dying and nothing I could do about it," Connolly said.

Diphtheria causes inflammation in the upper respiratory tract and can lead to heart and neurological issues.

Symptoms include fever, sore throat, loss of appetite and a swollen neck.

In severe cases, the neck swells so extremely it can lead to life-threatening complications, which is why the disease is also known as "The Strangler."

The infection is spread through direct contact and respiratory secretions.

Connolly runs an at-home daycare and estimates she will lose a week's income after suspending the business to protect her clients' children.

She is calling on other parents to immunize their children and wants the province to make vaccinations mandatory in Alberta.

"You need to know what I'm going through — the fear I am feeling and my child is feeling," Connolly said.

"We're not an underdeveloped country, we shouldn't be seeing this anywhere in the world but especially in a country like Canada."

'An abundance of caution'

In a statement from the Edmonton Public School Board, spokesperson Carrie Rosa said the affected school is working closely with AHS.

Custodial staff will disinfect any rooms that may have been contaminated "out of an abundance of caution," Rosa said.

Parents were notified of the situation in a letter on Monday.