An Ontario man is preparing to file a lawsuit against a Kitchener, Ont., clinic after he says he contracted hepatitis C following a colonoscopy in December 2013.

Jack Goss claims he became infected after a multi-dose vial of anesthetic was used on him, despite recommendations against the practice.

Goss underwent a colonoscopy at the Tri-City Colonoscopy Clinic on Dec. 24, 2013 to check for signs of colon cancer. He was relieved when the test came back clear.

But the bad news came a year later: A blood test found he was infected with hepatitis C, a virus that the local public health department says he likely got during the colonoscopy exam.

"I was really stressed out and I was shocked, and I was also a little angry that this could happen," Goss said. "I went in worried about colon cancer, I never thought I could get hep C from a colonoscopy."

A public health report confirms that the 48-year-old is among four patients who sought a colonoscopy at the Tri-City clinic and then contracted the chronic liver disease.

The report hypothesizes that the staff at the clinic may have used one multi-use vial of the anesthetic propofol on five different patients. Staff may also have reused the same syringe, unaware that the first patient carried hepatitis C.

Both the syringe and the vial may have become infected by tiny amounts of blood, passing on the virus to the four patients who followed.

Public Health Ontario guidelines from this year recommend the use of single-dose vials over multi-dose ones, as multi-dose vials "increase the risk of transmission of blood-borne pathogens and bacterial contamination."

The guidelines stress that when administering medications or vaccines, all needles and syringes used should be for single-patient use only.

In a statement to Â鶹ӰÊÓ, Tri-City Colonoscopy said it was working with the Region of Waterloo Public Health Office (RWPHO) to investigate the matter.

"The Tri-City Colonoscopy Clinic was troubled to learn that an infectious event may have occurred at its facility on December 24, 2013," the statement said.

"The Clinic understands that all patients who may have been affected have been contacted directly by RWPHO, which confirmed that it has no evidence of a risk to patients seen at the Clinic on any day other than December 24, 2013."

The clinic said RWPHO has assessed the clinic's infection prevention and control practices, and found they meet the recommended standards.

The statement also said the clinic has implemented advice from the office on how to "further strengthen" its infection prevention and control practices.

Outbreaks are preventable

Lawyer Rose Leto, who was retained by Goss, said the lapse at the clinic is disturbing.

"It's shocking and it's scary that simple sterility is not always being maintained in the clinics and in medical settings," she said. "It promotes fear that you could go in for a colonoscopy and walk out with hepatitis C. It's quite shocking."

But infectious disease specialist Dr. Michael Gardam, from Toronto's University Health Network, said that these types of outbreaks aren't rare. At least 50 have been reported across the U.S., with several in Canada -- including three in Toronto -- since 2011.

"This isn't the first outbreak associated with hepatitis C in that setting, and it won't be the last," .

He said while it is difficult to pinpoint exactly how contamination occurs in these situations, it is often linked back to the anesthetic and a contaminated syringe or multi-dose vial.

"The concepts are all the same: essentially these mutli-dose items are being used between patients without being properly discarded or cleaned appropriately," he said.

Gardam noted that these types of infections are "absolutely" preventable, and the error tends to stem from health-care providers seeing high numbers of patients, while facing pressure not to waste drugs.

"The only real way to stop this is to tell people that safety is the absolute No. 1 priority; if we waste drug, we waste drug. And you need to be given the time to make sure you're not making errors," he said.

Currently, in the U.S., there is .

As for the four patients who have contracted hepatitis C, they will likely have to be treated with costly medications as their disease progresses. 

While new treatments are very effective at eliminating the virus, they can cost up to $1,000 a day for up to eight weeks. There is currently a petition circulating to have Ontario cover the cost of the treatments.

With files from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip