Public urged to update vaccines after mumps, measles cases reported

TORONTO -- Public health officials and infectious disease experts are urging Canadians to check that their vaccinations are up to date as clusters of mumps are investigated in Ontario and Alberta, and measles cases are probed in Nova Scotia.

The viral infections are both covered by the measles-mumps-rubella (MMR) or measles-mumps-rubella-varicella (MMRV) vaccines. Experts say people need to ensure they've had the vaccines and some may need to get an additional shot to bolster their immunity.

"If you stop vaccinating then you start to be susceptible to these sorts of outbreaks," said Earl Brown, an immunology expert and professor emeritus with the University of Ottawa. "A vaccines is one of the best tools in health care."

In Toronto, public health officials said Friday that there were 17 confirmed cases of mumps in the city, all involving people between 18 and 35 years of age who had frequented west-end bars.

A Toronto Public Health spokeswoman said 60 per cent of those cases were not immunized or under-immunized. Lenore Bromley noted, however, that the risk to the general public was low.

In Alberta, officials said there were up to four potential cases of mumps in Edmonton, which typically sees zero to two cases each year. And a hockey team based in Medicine Hat, Alta. had seven players and a coach with mumps, Alberta Health Services said.

The mumps virus is found in saliva and respiratory droplets, and is spread from person to person through coughing, sneezing, and coming into contact with a person's saliva by sharing drinks or utensils, or by kissing.

Meanwhile, in Nova Scotia, seven cases of measles were confirmed by health officials this week.

Public health officials said it's important that people check their immunization records to ensure their vaccinations for mumps and measles are up to date.

Dr. Sarah Wilson, a medical epidemiologist with Public Health Ontario, said mumps cases that are reported typically involved people between the ages of 18 and 34.

She explained that many individuals in that age group may have only received one dose of mumps-containing vaccines as children, making them more susceptible to the virus.

That same group is more likely to engage in behaviours and activities in which mumps spreads easily, like playing on sports teams where water bottles might be shared, living in dormitories in close conditions and sharing drinks and food in bars, she said.

"These situations provide really rich opportunities for the mumps virus, if it's introduced, to spread easily in a population that might not be up to date with respect to mumps vaccine," said Wilson. "I think those are some of the potential explanation for why we're seeing more mumps these days, in particular in this age group."

Young adults should speak to their health-care provider and update their vaccinations if needed, Wilson said, adding that they could also take preventative measures, like ensuring they don't share drinks, once mumps is known to be circulating in an area.

Wilson explained that even those who get two doses of the vaccine can still sometimes end up with mumps -- as seen in 40 per cent of the Toronto cases -- as the vaccine is considered about 88 per cent effective at that point.

But while there are questions about how long immunity provided by two doses of the vaccine can last, Wilson emphasized that just getting the two shots is important

"The more important message is to make sure people in this age group ensure that they're protected with the two doses of mumps-containing vaccine," she said. "The risk of infection is much, much, much greater if you've only received just one, and certainly increased further if you've received zero doses."

Complications from mumps can include encephalitis, meningitis, painful swelling of the testicles or the ovaries, pancreatitis and hearing loss. Pregnant women who become infected with mumps during the first three months of pregnancy are at risk of miscarriage.

In Nova Scotia, the province's medical officer of health said all current cases of measles also involved young adults.

Dr. Trevor Arnason says the risk to the general public is low and said the cases were an opportunity for people to get their vaccines up to date.

Measles symptoms can include fever, cough, runny nose, red eyes, sleepiness, irritability, small white spots on the inside of the mouth and throat, and a blotchy rash on the face that spreads down the body.