Health Canada has asked Novartis, the maker of 20 per cent of the country’s flu vaccines, to halt distribution of two brands while they consult with European agencies about an odd finding.

Several European countries, including Italy, Germany and Switzerland, recently recalled the vaccines after seeing particles in them. The manufacturer had also reported during the summer that clumps of particles were discovered in the manufacturing process.

“It is a precautionary approach because the Europeans found something…these clumps or small particles not from outside but within the vaccine,” Dr. Paul Gully with Health Canada, said in an interview from Vancouver.

“They have obviously seen something so we are in the process of talking to them about what they saw and why we are doing what we are doing and I think in the meantime…it is prudent for us to do the same thing.”

The temporary halt of distribution involves two products – Agriflu and Fluad. The vaccines are produced in pre-filled syringes.

“We are at the beginning of the season...they are in the process of being distributed,” Gully said.

According to Health Canada, particles in vaccine vials are not uncommon and have no known impact on safety and effectiveness.

However, the agency said it issued its request to Novartis as a precautionary measure until a full review of the situation is completed.

"I don't think this means we have a big problem with the vaccine. It's a short-term pause to test things out,” Dr. Neil Rau, an infectious disease specialist, told CTV News.

"You worry that a story like this will make people think there is something dangerous about the flu vaccine, and that is definitely not the case. This is an abundance of caution.”

In a statement, Novartis maintains the vaccines are "safe" and that use in Europe so far has shown "no unexpected adverse events.”

European health officials expect to have their investigation complete in a couple of days.

“We want to get the info to health care providers and Canadians as soon as possible so we can then say there is no problem, no issue,” Gully said, stressing that Canadians should not avoid getting the flu shot.

“Please go forward and get immunized because any possible risk for the vaccine is infinitesimal and is far outweighed by getting the flu and what can be a really nasty disease,” he said.

 The Public Health Agency of Canada is also recommending that health care workers in possession of Novartis vaccines refrain from using them until the review is complete.