Thirty out of approximately 1,000 former endoscopy and dental surgery patients of the High Prairie Health Complex have tested positive for hepatitis B, hepatitis C or HIV, health officials in High Prairie told CBC News on Wednesday.

The tests were ordered last fall after it was revealed single-use syringes had been reused at the health complex to inject medication into intravenous lines for years.

Final numbers are not in yet, and the statistics could simply be a reflection of the prevalence of these infections in the general population, according to Alberta's acting chief medical officer of health, Dr. Gerry Predy.

"These infections they're looking for ... hepatitis B and C and HIV, are relatively common. So if you're going to test hundreds of people, you will get some positives," he said.

The number of people who tested positive for each disease has not been released.

In November, the health region announced it would offer blood tests to 1,381 former patients who may have been at risk of infection.

It is still not clear whether those who tested positive were infected because of a health-care procedure, and Predy said determining that may be difficult.

"Once they find somebody who got an infection, they will ... look at that person's experience, risk factors and see if there might be any other explanations," he said.

"It's a pretty involved process to do all these analyses."

A preliminary report on the individuals who have been tested is expected by the end of the month, Predy said.

Health officials have insisted the risk of infection from the reuse of the single-use syringes is very low.

However, the practice was stopped in High Prairie as soon as it was discovered.