To date, four Canadians have returned from travels testing positive for the Zika virus and the pressure is on to develop a vaccine in case the mosquito-borne virus develops into a global emergency, says Dr. Gary Kobinger, chief of special pathogens with the National Microbiology Laboratory in Winnipeg.

It's still not clear how much of a risk Zika virus poses to humans, according to public health experts. The virus has been around for decades and until recently wasn't considered serious. Only a minority of those infected experienced symptoms and most are mild, a skin rash and fever. People generally recover from Zika virus within a week.

ebola microbiology lab

The National Microbiology Laboratory in Winnipeg has partnered with researchers in the United States to develop a Zika virus vaccine. (John Woods/Canadian Press)

Last year, Brazil officials began linking Zika and a surge in birth defects known as microcephaly — or abnormally small heads. According to the Public Health Agency of Canada, "although there is mounting evidence to warrant concern, the investigation is ongoing to confirm whether Zika virus may be the cause of these microcephaly cases."

As researchers focus efforts on investigating a link between birth defects and Zika, the World Health Organization predicts the number of people infected with the virus could rise rapidly this year and may reach four million by 2017.

Dr. Kobinger, who will become the director of the Centre for Research in Infectious Diseases at Laval University in Quebec City in June, is hoping to develop a safe and effective vaccine before that happens.

He spoke with Up to Speed's Ismaila Alfa.

Ismaila Alfa: How concerned should Canadians be about Zika virus?

Dr. Kobinger: It's really an infectious disease that's of low risk to Canadians. It's a virus that is transmitted by mosquitoes primarily and the type of mosquitoes that carry the virus is not found in Canada.

Why do we know so little about this virus and this effect that it may or may not be having on babies?

It's a virus that's been circulating for over 60 years. Mainly from Africa to Asia and then it crossed east and appeared in the Americas. It's not linked to a very severe disease right out. It's one of those viruses that people have been working on but in a more limited fashion, unfortunately.

Now you are working on the vaccine for the virus. How long has the National Microbiology lab been working on the vaccine?

Only quite recently. We have been collaborating with a fantastic team in the U.S. at the University of Pennsylvania lab led by David Weiner. He's done vaccine development for dengue virus and West Nile and these are very closely related. A few months ago we got in touch and he told me about Zika. Since then we've been focusing on this. We've developed this group and we work so well together that we move fast.

How far along are you in developing this vaccine?

I'm amazed. This vaccine is already in clinical production. We hope that all the testing, as in the past, will be acceptable to regulators like Health Canada and the FDA and we'll be able to start enrolling volunteers, with their approval, and start a stage one clinical trial by mid or late-summer. That's a goal of course, we don't know if we can achieve it, but I think we can.

When could this vaccine be usable in humans?

Maybe by the fall. At least in 2016. It doesn't mean the vaccine is all of a sudden available for the entire population. The goal is to do our best but to be ready if there's an emergency. When we faced the (Ebola) outbreak in West Africa, we had a clinical lab but we didn't have human data for safety data. Now we want those safety data before we face a real emergency.

This interview was edited for length and clarity.