Health officials in Alberta are investigating an E. coli outbreak, but have yet to pinpoint the source of the bacteria.

Alberta Health Services is reporting 125 confirmed cases of E. coli in the province, but health officials are not sure if the cases are linked.

Most are concentrated in Calgary and Edmonton, where officials have confirmed 62 and 48 cases, respectively.

There were 13 confirmed cases of E. coli infection in the province at the same time last year.

Dr. Richard Musto told CTV Calgary that any time the province sees the number of E. coli cases exceed what is considered “normal”, an outbreak is declared.

“We’re looking for a common thread between the cases,” he said. “We still haven’t found it yet.”

This particular E. coli strain appears to be isolated in Alberta, suggesting it could be caused by locally-produced food items.

McMaster University microbiologist Herb Schellhorn said finding common food items consumed by everyone infected with E. coli is a challenging task.

“People can eat in restaurants or buy food from a variety of sources, and it can take a long time to identify a common element,” Schellhorn told CTV News Channel on Thursday.

According to Schellhorn, this particular strain of E. coli has a low infectious dose, meaning that it takes a “minute” amount of contamination to infect an individual.

He added that cattle serve as a “big reservoir” for the particular strain of the bacteria, pointing out that Alberta is home to a  large beef industry.

“About four per cent of cattle at any given time have the strain (of E. coli) and they can potentially, of course, contaminate water sources.” 

E. coli infections occur when an individual eats food or drinks water that is contaminated with human or animal feces, or through direct contact with a person who is sick, or animals that carry the bacteria.

To prevent the spread of E. coli, AHS recommends that individuals:

  • Wash hands often, especially after going to the washroom, preparing food, or touching raw meat
  • Cook beef to an internal temperature of at least 71C
  • Thoroughly wash vegetables and fruits before eating
  • Wash any tools or kitchen surfaces that have touched raw meat
  • Use only pasteurized milk, dairy and juice products
  • Use only treated or chlorinated drinking water