Province warns of measles spread as northern Alberta community deals with outbreak

Health officials are warning the public about a measles outbreak in northern Alberta that now includes six confirmed cases and they're worried about the potential for the virus to spread.

An outbreak in the northern Alberta community of John D'Or Prairie, which is part of the Little Red River Cree Nation, is being investigated.

The outbreak includes the first reported cases of measles in Alberta this year, according to the latest data.

According to the province, all six confirmed cases in the outbreak are members of the same household.

A letter posted Thursday from Indigenous Services Canada to Little Red River Cree Nation's Facebook page, which also includes information on where to get vaccinated, said an additional probable case of the disease in a second household is being looked into.

Little Red River Cree Nation said there have been no documented transmissions of measles as of Thursday in the John D'Or Health Centre and it's likely the initial infection was acquired outside of the community. 

Little Red River Cree Nation Chief Conroy Sewepagaham says all six confirmed cases are fully recovered, however, the risk of the virus remains.

Measles is highly contagious and spreads easily through the air, leaving health officials concerned about the potential for onward transmission.

"Measles is not just a mild childhood illness — it is a serious, highly infectious disease that can have devastating consequences," Dr. Mark Joffe, Alberta's chief medical officer of health, said in a statement.

Sewepagaham says mobile vaccination clinics are already making trips around the community to offer immunization shots, and will continue to do so into next week.

He adds out of an abundance of caution, all schools, early learning centres and daycares across the community will be closed from March 17 to 21 in an effort to bolster vaccine uptake in the community.

"Just to give the parents a week to bring up those vaccination rates," he said.

According to the province, 90 per cent of people who are not immune to measles and who come in contact with the virus, will become infected.

The health impacts can be serious and — in some cases — deadly.

Alberta Health says one in 10 people with measles will develop lung or middle ear infections, one in 1,000 will get encephalitis (swelling of the brain which can result in brain damage) and between one and three out of every 1,000 people will die.

Craig Jenne, a professor in the department of microbiology, immunology and infectious diseases at the University of Calgary, says as measles cases break out in other jurisdictions in Canada and the U.S., it's important that the province continues to monitor local infections.

"[Measles] can have very negative outcomes, we have seen that, unfortunately already in the Ontario outbreak where we've lost one child, and in the U.S. outbreak, where we've lost both a child and an adult," Jenne said.

"This is a dangerous virus."

He said that because measles is extremely infectious and difficult to contain, it requires about 95 per cent of people in the community to be fully vaccinated to achieve herd immunity.

However, childhood vaccination rates have dropped in recent years. According to provincial data, in 2023, 69.3 per cent of Alberta children were fully vaccinated with two doses of the measles vaccine by the age of two. In several parts of the province, the immunization rate was well below 50 per cent.

"[That's] not remotely close to the levels we need," Jenne said.

"If measles is introduced into those parts of the province or other provinces — this is not an Alberta-only effect — that is where measles can spread quite rapidly."

Measles can linger in the air for hours after an infected person leaves a room, Jenne said. As few as one to two individual virus particles can cause an infection.

Cora Constantinescu, a pediatric infectious diseases specialist and associate professor with the Cumming School of Medicine at the University of Calgary, says she worries it's just a matter of time until the disease appears in other parts of Alberta.

"We know people like to travel. We know that spring break is approaching," she said.

"It's just a matter of time before we're going to see local cases coming from these outbreaks that right now might seem far away but really are not."

Constantinescu said measles can be contagious before symptoms begin to appear, and the best defence against the disease is to be vaccinated against it.

"In Alberta, we offer [vaccinations] at 12 months and at 18 months of age, if you are fully immunized and your child is fully immunized, this is not something you need to worry or panic about," she said.

Provincial health officials are also urging vaccination.

"No one should have to endure the consequences of a disease we can prevent," Joffe said in the statement.