HIGH PRAIRIE, Alta. - Up to 2,700 patients, including children, need to be tested for HIV and hepatitis because a handful of nurses in a northern Alberta hospital injected drugs with used syringes for nearly two decades.

Health officials said the risk of infection was low, but it was enough to put people in the community on edge.

"People are very frightened and rightfully so," said Pearl Calahasen, the government member for the area who said has been getting dozens of calls from people who may need to be tested.

"I think when people's lives are threatened in any way, shape or form that fear sets in."

Health officials revealed Monday that a handful of nurses at the High Prairie Health Complex were routinely injecting drugs into patient's intravenous lines with the same syringe.

Blood tests were being arranged for 1,300 patients who had endoscopy procedures over four years dating back to March 2004.

As many as 1,400 patients who had dental surgeries at the same hospital dating back to 1990 also needed to be tested, said Dr. Albert de Villiers, the region's medical health officer.

"We are assuming at this point that a large number of them will be children because it's more children that get dental surgery," he told a news conference Monday.

He said no infections have been found and the risk is very low, but "it is not an acceptable practice that we have identified and that's why we stopped the practice."

Infections disease experts in the U.S. have found cases of serious infections linked to using syringes on more than one patient.

Since 2001, the Center for Disease Control in the U.S. has identified several hepatitis C outbreaks associated with syringe reuse and other lapses in recommended infection control practices.

The problem in High Prairie was discovered earlier this month by a manager who observed a nurse using a used syringe. De Villiers said it took three weeks to sort out which patients may have been infected and whether blood testing was required.

Patients will be contacted by phone and registered mail for testing, which will be co-ordinated by Alberta Health.

"It might be tricky to track down all the patients," said de Villiers. "We will try our best."

The injections were performed by both registered nurses and licensed practical nurses, who both receive training on safe injection practices, said a spokesman for the health region.

Phil Hassen, chief executive officer of the Canadian Patient Safety Institute in Edmonton, said it's too early to say whether it was incompetence on the part of nurses.

"Why did the nurses do what they did?" Hassen asked in an interview. "So often there are a series of things that contribute to this."

"We need to be sure we know what the problem is. We need to fix this thing and we need to learn from it, so it never happens again."

But Margaret Hadley, president of the College and Association of Registered Nurses of Alberta, said there's an onus on registered nurses to be aware of infection control standards and to ensure that they're being followed.

"Part of that behaviour is expecting them to question any policy or procedures that are inconsistent with (patient safety)."

Robin Laughlin, a physician who does most of the endoscopies in the town and has worked in the region for 35 years, said he was surprised and disappointment by the news.

Laughlin said he doesn't know why the syringes were reused or what happened to quality control. "That's obviously one of the questions that has to be answered."

In endoscopy, a fibreglass scope is inserted into a patient's bowel or stomach and beams back video images to scan for cancers, colitis and digestive problems. Prior to the procedure, the patient is sedated by a syringe inserted into the intravenous line.

Intravenous lines sometimes have blood seeping into them from a vein and a syringe could come in contact with the blood and possibly spread an infection.

Alberta's Quality Health Council is investigating, but hospital staff were reportedly reluctant to answer questions.

"We're talking about a group of staff isolated in one department in the facility," said Tim Guest, a vice-president for the local health region. "It's not widespread in the entire facility. (It's) a very small number of employees -- less than five."

Health Minister Ron Liepert said he suspects human error is the root cause, but said the investigation will not focus on laying blame.

"We have a health system that is made up of hundreds of thousands of people. They're all human beings. There will be mistakes that will be made," said Liepert.

"As soon as we start pointing fingers or wanting to lay blame, people are not going to want to co-operate."

Liepert took heat in the legislature Monday from Calahasen, a former cabinet minister, who questioned whether her family and friends will lose faith in patient safety.

"Can they still trust the health-care system even when these kinds of things continuously happen?" she demanded of Liepert. "How long will it take to track all these patients down to test them so they can be sure they're not infected?"

Heather Smith, president of the Alberta Union of Nurses, said she's anxious to learn specific details about what was being done, why it was being done and for how long.

"Who was involved in establishing that protocol or that practice?" asked Smith, whose union represents 24,000 registered nurses. "Was this being driven in any part by a need to minimize costs by reusing the syringes?"

The Alberta Union of Provincial Employees cautioned that unsound practices should not be blamed on front-line workers.

"We do not think it would be in any way appropriate for blame in this case to be assigned to working people who are doing their best in very difficult circumstances," union president Doug Knight said in a release.

Knight said health-care employees have been "raising warning flags" for years about understaffing, overwork and cost-cutting policies that pose a risk to patients and hospital staff.

High Prairie, located on the west end of Lesser Slave Lake, has a population of 3,000, but administers to 17,000 in its service area. It is a regional centre serving a mixed farming, forestry and oil and gas community.

This is the second case involving poor sterilization procedures at an Alberta hospital in recent years.

In early 2007, poor sterilization techniques and the outbreak of a superbug forced 3,000 patients from St. Joseph's Hospital in Vegreville east of Edmonton to be tested for infection.

The 25-bed hospital was closed for several weeks after instruments were recirculated with flecks of blood and dead tissue on them.

A class-action lawsuit has since been filed, claiming the hospital failed to ensure the instruments were properly cleaned.

The opposition parties said Premier Ed Stelmach's government has failed to enforce heightened standards for infection prevention promised after the Vegreville outbreak.

"Imagine one of these blood-borne infections infecting someone," said Liberal legislature member David Swann.

"These are life-threatening illnesses. It's totally unacceptable. "

"This government spends more money to educate drug addicts about not reusing syringes than they do for health professionals," said NDP Leader Brian Mason.

"This is simply appalling and could happen again".