EDMONTON -- Health officials in Edmonton are warning passengers who arrived in the city on a flight from Vancouver this month that they may have been exposed to measles.

The warning further extends to anyone who was in Edmonton International Airport during the hours immediately after the Air Canada plane landed on April 9.

Alberta Health Services issued a news release Saturday stating that passengers and crew on Air Canada Flight 248, which departed Vancouver at 8:30 p.m. and arrived in Edmonton at 9:35 p.m. may have been exposed.

It says anyone who was at the airport from the time the plane arrived up until 2 a.m. the following morning could also be at risk of contracting the illness.

Dr. Marcia Johnson, a medical officer health in the Edmonton zone, said the passenger was a child with measles who arrived in Vancouver from the Philippines.

"Measles is extremely contagious. It spreads through the air. You just have to be walking through an air space where a person with measles has walked through within two hours and you can be exposed to measles," Johnson told reporters on Saturday.

"Every single measles case that develops is a spark to expose other people."

Johnson said Alberta officials have contacted affected agencies in B.C. to alert them about the case.

Vancouver Coastal Health wasn't able to immediately say on Saturday afternoon whether a similar warning has been issued there.

A spokesperson for Vancouver International Airport said no warning has been issued by the airport, noting that such a warning would be prompted by provincial health officials.

Johnson said she didn't know how many passengers were on the Vancouver-to-Edmonton flight. Efforts may be made to obtain a passenger list and contact those people directly, she said, but she noted such efforts could take time and health officials wanted to issue their warning as quickly as possible.

Alberta Health Services said people on the plane or in the terminal who have not had measles before, or who have not received two doses of the measles vaccine, should be on the lookout for symptoms.

It also said anyone who experiences symptoms should stay home and call the province's health advice line before visiting a doctor or health care facility.

Johnson said she couldn't release information about the age of the child, or if the child was a resident or a visitor to Canada.

She said the child didn't require hospitalization and is now recovering at home.

Measles is a respiratory disease caused by a virus, involving a red whole body rash.

British Columbia is currently in the grips of a large outbreak, with at least 375 cases so far, while Alberta has confirmed 15 cases so far in 2014.

Health officials in Manitoba confirmed two new cases of the disease on Thursday, bringing the total number of cases there to seven.

On Friday, officials expanded the list of businesses on a Winnipeg street where people may have been exposed to measles, and said people who attended a bull-riding event at the MTS Centre last Wednesday may have been exposed.

Most people who get the measles survive, but between one and three cases out of every 1,000 can be fatal.

Johnson said the Philippines is also in the midst of a measles outbreak.

She said it usually takes 10 to 12 days from exposure to measles before symptoms occur. That means anyone on the plane or at the airport who may have contracted measles from the infected child would only just be experiencing symptoms now, she said. So far, she said no one else is known to have contracted measles from the child.

People who have been immunized or have had measles before cannot spread it to anyone else, Johnson said.

Earlier this month, Alberta health officials asked more than 100 Calgary students to stay home for the next two weeks because they have not been vaccinated for measles.

Johnson said measles cases this year are a result of lower immunization rates and worldwide outbreaks.

"In this day and age these diseases are global. And thus you really have to protect yourself with vaccines against diseases even though they might be relatively rare here. They're just a plane ride away," Johnson said.

"From a public health perspective we feel kind of sad because this is preventable. It is completely preventable."

Johnson said it was fortunate that the child passed through the terminal at a time when it wasn't particularly crowded.

"In some ways it's kind of good that it was so late at night and early in the morning. I don't know if you've ever gone to the airport for a 6 o'clock flight but it's really busy at that time," she said.