Confirmed cases of E. coli rise in northern Ontario

More confirmed cases of E. coli were linked to aHarvey's restaurant in North Bay, Ont., on Tuesday.

The number of confirmed cases rose to 35, health officials said, up seven from Monday.

Health officials also said they know of a total of 158 suspected and confirmed cases of E. coli O157:H7 in the outbreak,involving eight health units in Ontario.

This E. colioutbreak was likely caused by human error rather than undercooked hamburger meat, saidRick Holley, a professor of food sciences at the University ofManitobawhohas worked with Agriculture Canada.

Since the outbreakwas isolated to just one Harvey's location in North Bay on Oct. 12, Holleybelieves the problem arose in-house, such as a surface that was improperly cleaned, ormishandling of meat or produce.

"If this were a case of uniformly contaminated raw material, you would expect to find that there would be some other outbreaks developing from other Harvey's stores in their chain," said Holley. "This is a locally generated problem."

Almost all of the patients, who range in age from a baby to the very elderly, are now recovering at home.

"We are doing everything we can to look for the specific source of the E. coli," saidDr. Catherine Whiting, medical officer of health for the North Bay Parry Sound District Health Unit.

"However, in the majority of these types of outbreaks, despite everyones best efforts, the specific source is never found."

The numbers of those becoming ill due to E. coli is slowing, which indicates the outbreak has peaked and is beginning to decline, the North Bay health unit said.