Montreal's health authority says a person infected with measles visited the airport and seven businesses in Pointe-aux-Trembles and the Mercier-Hochelaga-Maisonneuve borough last month.

Now the health agency is warning the population about possible exposure to the highly contagious virus during the five-day period.

The agency says a woman who was infected arrived on an Air Canada flight from Moncton on Sept. 20, and spent some time over the noon hour in the arrivals area at Trudeau airport.

The list includes a supermarket in the borough of Mercier-Hochelaga-Maisonneuve as well as a restaurant, convenience stores, a Canadian Tire and a hotel in Pointe-aux-Trembles.

The agency has a complete list on its website.

Symptoms include fever, cough, runny or stuffy nose, red and watery eyes and tiny white spots in the mouth.

AVIS À LA POPULATION | Exposition possible à la <a href="https://twitter.com/hashtag/Rougeole?src=hash&ref_src=twsrc%5Etfw">#Rougeole</a> dans des lieux publics de l’Est de <a href="https://twitter.com/hashtag/Montr%C3%A9al?src=hash&ref_src=twsrc%5Etfw">#Montréal</a> et à l’Aéroport international Pierre-Elliott-Trudeau de Montréal<br>➡️<a href="https://t.co/CBTWVzKiU0">https://t.co/CBTWVzKiU0</a> <a href="https://t.co/aWjM15uN3h">pic.twitter.com/aWjM15uN3h</a> —@santemontreal

People are considered protected if they already had a medically confirmed case of measles or have been inoculated.

Those not vaccinated should do so through their doctor or the CLSC, public health says.

People are being told to call Info-Santé by dialling 811 with health concerns, and, if necessary, they will be referred to the nearest place where they can go for evaluation and treatment.

"This vaccine is free, safe and very effective," public health says.