Number of mumps cases in Manitoba doubles; outbreak expected to continue for months

The number of mumps cases in Manitoba has more than doubled since the outbreak started in late 2016, and the outbreak is gaining speed rather than slowing down.

Outbreak of mumps that started late last year is gaining speed rather than slowing down, health officials say

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The number of mumps cases in Manitoba has more than doubled since the outbreak started in late 2016, and the outbreak is gaining speed rather than slowing down.

Between December 2016 and February 2017, 78 cases of mumps were reported in Manitoba. That brings the total number of cases since the outbreak began to 139.

Normally, Manitoba sees five cases of mumps per year.

"The good news about this is we've actually had very few [cases] where there have been serious outcomes," said Dr. Richard Rusk, Manitoba Health's medical officer assigned to vaccines. "We haven't ended up with people in ICU."

The province has seen hospitalizations, though, and it may see more as the outbreak is expected to last into late spring.

The province is working to slow down the outbreak by investigating each case and the people who came in contact with the infected individual. They're also trying to get the word out about vaccines.

"Pretty much [we] use our own real weapon that we do have, and that's ensuring that we get everyone up to date with their vaccine," said Rusk.

Mumps causes swelling of the glands and an extremely sore throat, and can lead to complications. The most severe outcomes are infertility, due to swelling of the testicles, or meningitis, which can be fatal.

The latest outbreak started with a sports team at the University of Manitoba, and has primarily affected athletes.

Now, a hockey team in Brandon and a rural Manitoba hockey team have also dealt with cases of the mumps.

"They'll end up sharing water bottles. They'll end up taking a hit and their saliva is spread around," said Rusk.

The province is working with Sport Manitoba in efforts to curb the spread.

Part of the problem is the low number of people who are vaccinated against the mumps. In Manitoba, about 70 per cent of people are vaccinated, and the vaccine is only about 85 per cent effective after 10 years.

In fact, some of the individuals contracting the virus were vaccinated as children.

The province isn't advising anyone who has already had the vaccine to be vaccinated again, but Rusk said that could change.

"We ask that every single time we meet, but there isn't good evidence that [getting vaccinated twice] will change the direction of the outbreak, that it will reduce numbers of cases and that sort of stuff," said Rusk.

He said if there are more severe outcomes for patients in Manitoba, the province may consider changing that advice.

"We would be way more aggressive with our messaging. In that sort of setting, we would consider a third vaccination or focusing on specific populations at higher risk. We'd ramp up our typical public health approaches," said Rusk.