After a big surge in mumps cases this year, Vancouver Coastal Health is urging young adults to check their vaccination records and make sure they're protected.
The health authority has recorded 13 cases in the last month alone, and a total of 80 since February. That compares to 86 in all of 2016 and an average annual rate of 32 cases between 2011 and 2015.
"It tends to be young adults who've received only one dose of mumps vaccine as part of their routine childhood vaccinations and who tend to be going out into congregate settings, whether that's working at Whistler or going into residence at university," Réka Gustafson, a VCH medical health officer, told CBC News.
People who were born between 1970 and 1995 have generally received just one dose of the measles, mumps, rubella (MMR) vaccine, Gustafson explained.
"That's what we believed was needed for lifelong protection. We now know that, in fact, you need two doses of vaccine for lifelong protection, and, as of 1996, all children have received two doses," she said.
Canucks sidelined by mumps
The average mumps patient in the current outbreak is about 25 years old, and most cases have been in Vancouver. Earlier this year, several young players with the Vancouver Canucks were sidelined by the illness.
The mumps virus spreads through saliva or mucus, and a person can become infected even if they're standing two metres from a sick person, according to VCH. The infection causes fever and swelling of the salivary glands.
The MMR vaccine is available for free in most clinics and family doctors' offices in B.C. People born between 1957 and 1969 who have received just one dose already have sufficient protection, according to VCH.
With files from Dan Burritt