May 1, 2014 5:29 pm

Is the measles vaccine effective? What health officials say

CALGARY- As Albertans rush to get immunized against the measles outbreak, there are concerns about just how effective the vaccine is.

Of the 22 cases recorded in the province this year, at least four involved people who had been immunized.

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“What we’re seeing now, is even in fully vaccinated populations you end up with infections,” says Larry Solomon, research director with the Consumer Policy Institute in Toronto.

The U.S Centre for Disease Control reported 649 cases of measles between 2005 and 2011, and found 53 cases involved those who’d gotten one dose of vaccine. Another 31 people had been fully immunized.

Officials maintain the MMR vaccine is 99 per cent effective with two doses, but studies have found up to 10 per cent of the population still won’t be immune.

“In some cases, they’re getting some antibodies that protect them for a while, in other cases there is no protection at all,” Solomon explains.

The vaccine is proving effective in Quebec, where there hasn’t been a single recorded case this year. That’s a big change from 2011, when 800 children fell ill, prompting the government to strengthen its immunization policies.  70, 000 children will vaccinated during an aggressive campaign that year that required students be vaccinated before they could return to school.

“What they basically did was they created a group that was now protected,” says Dr. Mitch Shuylman from Montreal’s McGill University Health Centre. “Now you come into 2014, even if the virus were to be introduced into the community there are so few children who could give it a place to grow, that you wouldn’t have a chance for an outbreak to spread.”

Drop in clinics will reopen in Calgary on Saturday.


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