TORONTO -- A clinical trial of the made-in-Canada Ebola vaccine will be conducted in Halifax, Health Canada and the Public Health Agency of Canada announced Friday.

The location of the trial is likely to come as a serious disappointment to Ebola researchers at Canada's National Microbiology Laboratory in Winnipeg, where the vaccine was created. At least some wanted to volunteer to help test the vaccine.

"That's a bit of a sore point," a source familiar with the discussions said about the decision. The person spoke on condition of anonymity.

Like others in their field, scientists in the Winnipeg lab's Ebola research program have been waiting for years for a chance to be vaccinated against the deadly viruses with which they work. They had hoped the clinical trial would be performed in Winnipeg.

But the Public Health Agency of Canada suggested the Winnipeg lab staff could not take part in the trial because they may have an emotional investment in the vaccine. The agency added, though, that the researchers will be able to volunteer for future trials of the vaccine.

"Phase 1 clinical trials require, for the purposes of scientific credibility, that the participants not have a vested interest, one way or the other, regarding the outcome of the trial," the agency said in an email from Stephane Shank, chief of media relations.

"Notwithstanding the above, plans are in place to provide Winnipeg employees with the opportunity to participate in future clinical trials, for which they would be eligible. Once plans for these have been confirmed, we will be announcing them."

The contract to do the work was given to a research consortium set up to do vaccine trials as a part of a rapid public health response, called the Canadian Immunization Research Network. It was first established -- under a different name -- to do clinical trials of H1N1 flu vaccine during the 2009 pandemic.

The network is funded by the public health agency and the Canadian Institutes of Health Research, which have allocated $300,000 for this clinical trial.

The network itself proposed to do the trial in Halifax, one of 10 trial sites in the network, and one of its most experienced, said Dr. Scott Halperin, lead investigator for the immunization research network.

"The most important reason for not doing it in Winnipeg is we did it at the site that had the most experience in Phase I studies," said Halperin, who is also director of Dalhousie University's Canadian Center for Vaccinology, where the trial will be conducted.

The trial protocol specifically excludes people who work with filoviruses -- the virus family to which Ebola belongs -- so even if the trial had taken place in Winnipeg the National lab's Ebola researchers would not have been able to enrol, he said.

Halperin said that in Phase I trials -- designed to establish that something is safe to give to people and to determine the size of a dose -- it is important volunteers do not have what is called a therapeutic misapprehension. "People should not go into the study thinking they're going to get benefit."

But surely scientists are well versed in issues of informed consent? Wouldn't they understand this? "Intellectually, but not necessarily emotionally," Halperin replied.

He also noted that the doses being tested in the Halifax study might not be protective; the trial will test low doses to see if they work.

The lower the dose per person, the farther the existing supplies of vaccine will stretch. But if a researcher was randomly assigned to get the lowest dose and it was not protective, the person wouldn't then be able to go into another trial to try to get a more effective dose.

"To me, somebody who's at risk is much better waiting until after a Phase 1 study into a Phase 2 study where you're really confirming the dose and you've already narrowed things down," Halperin said.

The trial will begin recruiting 40 volunteers between the ages of 18 and 65 next week. Ten each will receive one of three different doses and the remainder will get an injection of saline as a placebo.

The volunteers will each be paid $1,125 (plus parking fees) to take part. Subjects will need to attend the clinic on multiple occasions and the stipend per visit varies depending on how long it lasts, Halperin explained.

The aim is to see if a low dose of vaccine will trigger a protective response. Canada has donated between 800 and 1,000 vials of the vaccine to the World Health Agency. But it won't be clear how many people could be immunized with the donated vaccine until trials like this one show what is needed to make an effective dose.

"If our lowest dose works, that means rather than 1,000 doses, it's one million doses. So those numbers can go up dramatically if it's effective (at a low dose)," Halperin said.

Several other trials with this vaccine have already started or will start soon, in Bethesda, Md., Geneva, Switzerland, Hamburg, Germany as well as at sites in Gabon and Kenya. In at least some of these places, people who are potentially taking part in the Ebola containment response are being allowed to volunteer.

The vaccine has been licenced to NewLink Genetics, a small biotech company based in Ames, Iowa.