Health officials in British Columbia's Fraser Valley – trying to stem a serious whooping cough outbreak – want all adults to get vaccinated.
More than 155 cases have been reported in the valley east of Vancouver since December, but the medical officer of health says the number might be as high as 400-500.
The outbreak – the first in seven years – began just before Christmas in Hope and moved west to Chilliwack and Agassiz.
"We have an outbreak that's spreading and we're trying to make sure we get as much vaccine into the community as possible because that's what protects the children," Dr. Paul Van Buynder, Fraser Health's Chief Medical Health Officer told CTVNews.ca.
Whooping cough is a highly contagious bacterial infection that can be deadly in young children and babies because they have smaller airways. It's spread though the air when those infected cough and sneeze.
"This is a nasty disease for little babies," Dr. Van Buynder said. "If you get this when you're very young, there's a significant mortality."
The illness starts off like a common cold but develops into a persistent cough, which can last months. It gets its name from the distinctive noise – which sounds like an animal yelp – made after a coughing spell. The coughing may be so bad it makes a person gag or throw up. It can also cause convulsions.
Most little children catch the illness from an adult, Dr. Van Buynder said, which is why the B.C. immunization appeal is zeroing in on adults, especially those who are in close contact with children.
The whooping cough vaccine doesn't work well on babies. They need three doses of the vaccine delivered over six months to be fully protected.
None of the cases in the Fraser Valley outbreak has been fatal. An outbreak three years ago in Saskatchewan killed five children.
Another form of protection for babies is to vaccinate the mother during pregnancy, the medical health officer added. He suggested pregnant women discuss vaccination with their doctors.
Whooping cough outbreaks still flare across the continent because vaccinations administered in childhood wear off after about a decade. That's why all adults are urged to get booster shots, Dr. Van Buynder said.
