Officials in Canada are investigating a major paediatric outbreak of E. coli that appears to originate in a kitchen that makes meals for nursery children.

Alberta’s chief medical officer, Dr Mark Joffe, told reporters on Tuesday the kitchen was inspected after a surge in children visiting emergency rooms.

Doctors swiftly “linked” the cases to “one centralised kitchen”, he said.

Officials have not yet determined the exact source of the outbreak, which has so far sickened 264 children.

The kitchen is operated by a company called Fueling Brains, which provides food to daycare centres around the city of Calgary – where the outbreak is taking place – as well as the city of Saskatoon.

At least six children are undergoing dialysis after suffering kidney failure. More than two dozen others have been diagnosed with haemolytic uraemic syndrome, a disease that harms the kidneys. The children are under the age of five.

The number of patients continues to rise, officials say.

The kitchen thought to be the origin of the outbreak provides food to all 11 of the affected daycares, according to the Calgary Herald.

All of the centres were shuttered by emergency officials, but six have been allowed to re-open. Officials say it is safe for children to return to the facilities.

An inspection of the kitchen was conducted by Alberta Health Services on 5 September, one day after officials declared an E. coli outbreak.

The health inspectors’ report noted several critical violations, including a pest infection and issues with how food was being handled and transported.

“Two live adult cockroaches were observed on the sides of stainless steel equipment around the dishwashing area,” the report says.

It adds that traps set up near two sinks “had at least 20 cockroaches on the sticky pads each” and that a “sewer gas smell” was detected in the kitchen.

Food was also being transported without proper cold storage and sanitising liquid was being improperly mixed, resulting in an ineffective disinfectant solution.

“Food was not being handled in a manner that makes it safe to eat,” health inspectors wrote in the report.

The kitchen is closed and “will only reopen once we are absolutely satisfied that it is safe,” Dr Joffe said.

In a statement send to CBC News on Tuesday, Fueling Brains said it quickly took action after being notified of the outbreak.

“While the kitchen remains closed, all food will be sourced by external providers,” reads the statement by company vice president Kent Hehr.

It adds that the company has been communicating with parents and staff.

“Throughout this process, we have remained transparent, co-operative, and have taken immediate action wherever possible.”

E. coli is a bacteria infection which can be found in the gut and faeces of many animals, especially cattle.

Symptoms include diarrhoea, stomach cramps and sometimes fever. About half of those infected will have bloody diarrhoea.

These symptoms are usually noticeable three to four days after they have been infected, but can start at any time between one and 14 days afterwards and can last for up to two weeks.

A small number of people who become infected go on to develop a condition called haemolytic uraemic syndrome which can lead to kidney failure and death.

Source: NHS