Alberta Health Services is warning the public that a person with infectious, lab-confirmed measles has been in public settings in Sherwood Park, Nisku and Edmonton this month.

In a health advisory issued Monday, AHS provided a list of locations the adult with measles attended, along with the dates.

They include a shopping mall, restaurant, construction company, drug store and two hospital emergency departments.

Other people who were in the same places during those dates and times may have been exposed to measles, an extremely contagious disease which is spread easily through the air. There is no treatment for the potentially fatal disease, which can cause seizures and brain damage.

It can be prevented through immunization.

AHS Medical Officer of Health Dr. Chris Sikora said the infected individual likely contracted measles while travelling.

"It highlights and serves as a reminder that communicable disease — measles is one of these — is a simple plane ride away," he said. "We have to take that time to consider where are we going, what are the activities we want to do there, and is there an ability to protect ourselves with either immunizations or other medications to help ensure that ourselves and the people that we travel with remain healthy."

These are the dates and exposure locations:

May 9: Sherwood Park Mall, 2020 Sherwood Dr., Sherwood Park; 3 p.m. to 5:45 p.m.

May 10: Sherwood Park Mall, 2020 Sherwood Dr., Sherwood Park; 3 p.m. to 5:45 p.m.

May 11: Sherwood Park Mall, 2020 Sherwood Dr., Sherwood Park; 2 p.m. to 4:30 p.m.

May 11: Smilie's Village restaurant, 981 Fir Street, Sherwood Park; 6 p.m. to 10 p.m.

May 15: Shoppers Drug Mart, #500 2020 Sherwood Dr., Sherwood Park; 9 p.m. to 11:30 p.m.

May 16: Carmacks Construction 701 25 Ave., Nisku; 4 p.m. to 6 p.m.

May 16: Strathcona County Health Centre emergency department, 2 Brower Drive, Sherwood Park; 8 p.m. until May 17, 5:30 p.m.

May 17: University of Alberta Hospital emergency department, 8440 112th St., Edmonton; 4 p.m. to 8 p.m.

People who many have been exposed to measles during this period, May 9 to May 17, are no longer eligible for a preventative vaccine, as it's effective only up to three days after exposure, Sikora said.

They are encouraged to review their immunization history and arrange vaccination if they have not received two doses of the free MMR (measles, mumps and rubella) vaccine.

"It is a serious disease. It's something that is vaccine preventable," Sikora said.

"If people are susceptible or people haven't been adequately protected against measles, they may actually contract the disease unfortunately quite efficiently."

AHS said anyone with questions should call Health Link at 811 before visiting a healthcare facility or provider.

We have been seeing both in some North American pockets, but worldwide, increased numbers of measles. - Chris Sikora, AHS Medical Officer of Health

People who were in the Shoppers Drug Mart on May 15, Carmacks Construction on May 16, the Strathcona County Health Centre emergency department on May 16 and May 17, and the U of A Hospital emergency department on May 17 and who are pregnant, under one year of age, or who have a weakened immune system due to disease or medication are encouraged to contact Health Link at 811 for further assessment.

These individuals may be eligible for prophylactic medication to prevent measles, Sikora said.

People should monitor for symptoms for three weeks following the potential exposure date. Symptoms include:

Fever of 38.3 C or higher; and

cough, runny nose and/or red eyes; and

a red blotchy rash that appears three to seven days after fever starts, beginning behind the ears and on the face and spreading down the body and then to the arms and legs.

Sikora said this is the third measles case in Alberta this year. Last year, there were eight cases. In 2017, there were two, he said.

"We have been seeing both in some North American pockets, but worldwide, increased numbers of measles," he said.

Albertans uncertain of their own or their child's immunization history can call Health Link at 811 to discuss.