Daycare E. coli outbreak climbs to 310 cases, as AHS says hospitalized children 'stable'

Alberta Health Services says the number of those infected with E. coli following an outbreak linked to Calgary daycares continues to rise, nearly two weeks since the initial exposure to the bacteria is believed to have occurred. 

Speaking to the media on Wednesday afternoon, Dr. Tania Principe, a pediatric emergency physician at the Alberta Children's Hospital, said that 310 people have now tested positive for E. coli, up from the 264 cases reported Tuesday. 

Dr. Principe added that 21 patients remain in hospital. Of those, 20 patients, all of them children, are battling hemolytic uremic syndrome (HUS), a severe complication of shiga-toxin producing E. coli. Seven children are on dialysis. 

She said that all 21 hospitalized patients remain in stable condition. 

"Thankfully the kids are doing well and our aim is that they'll be coming off dialysis and not needing further care," said Principe.

"[Hospitalized patients] are getting regular blood work and we want to see improvement in that blood work to know that they're safe to go home."

Principe said that the jump in total case numbers this week was anticipated by AHS as more tests come back, and that some of these confirmed cases may be asymptomatic. 

"This increase in numbers we're seeing has more to do with when we're getting results from the lab on those tested previously. But actually, clinically in the [emergency department], we're seeing a significant decrease in the number of children presenting with illness," she said.

"If we're able to continue to contain that secondary spread, we should have been through really the largest hump now."

Dr. Francesco Rizzuti, the medical officer of health with Alberta Health Services Calgary zone, said that a food source of the outbreak has still not been found. 

Rizzuti said that samples from leftover foods and foods still in the freezer were gathered from the central kitchen shared by the affected daycares by public health inspectors.

• Cockroaches, previous violations at kitchen used by Calgary daycares as E. coli outbreak toll climbs to 264

"Anything that we could test, we have taken for testing and [they] are working through the lab process," said Rizzuti. 

"To my knowledge, all of these so far have been negative."

Rizzuti said he could not give a specific timeline as to when AHS's investigation into the source of the outbreak would be completed. 

"We are working as efficiently as we can, but also want to ensure that we are being robust and thorough in this investigation."

Principe noted that there have been 18 secondary transmissions of the infection, all within households of those who were initially exposed. 

"This is heartening and shows that our quick response and communication with families have helped to limit that spread."