MONTREAL - The number of confirmed measles cases in Quebec has jumped to 119 and health authorities northeast of Montreal are bracing for even more.
All of them are epidemiologically related and involve unvaccinated children and adults in the Lanaudiere region.
The cases are centred around one religious group from the region, La Mission de L'Esprit-Saint, a member said Wednesday.
While health officials have not identified the group, Emmanuel Francoeur, the director of the spiritual movement's musical school, told The Canadian Press the majority of cases come from his community.
Authorities have said the cases are part of one chain of transmission that started when a person with the order became infected at Disneyland in California and returned to the province.
It isn't the first time measles has hit the community. A Health Canada report notes the group was struck by 22 cases in 1994. While they refused immunization, they did co-operate by limiting social contact to minimize the spread, much like this time.
"The majority of these cases, the crisis is over and they've returned to good health," Francoeur said in a phone interview.
Officials said Wednesday two people contracted pneumonia and a dozen people are hospitalized.
One of the 119 cases was a child who attended a local elementary school while contagious just before spring break.
Officials have identified 51 staff and 114 students as not being adequately vaccinated among nearly 700 people across three pavilions at the Ecole integree St-Pierre.
"The level of contact is varied — not all students had the same level of contact with the single case," Dr. Joane Desilets told a news conference in Joliette.
All staff and students will have their vaccination records checked, information will be offered to parents and shots will be available Thursday.
"They will have the choice to accept or refuse vaccination," Dr. Muriel Lafarge, head of the local health authority, told the same news conference. "But if the person refuses, they will be taken out of school for two weeks.''
The 14-day period would follow the last reported case, Lafarge said.
Desilets said the increase was not unexpected given the group in question includes about 20 families, each with between seven and 10 children.
"These people were all unvaccinated and all came from very large families and all developed the illness," she said. "That is why we have the large number of cases we have today."
Desilets says more cases are likely to come. Although infected families co-operated and stayed home, they may have come into contact with unknowing infected patients.
Francoeur said it's unfair to describe the religious group as being anti-vaccination but he didn't deny that many count themselves among the 10 per cent of the Quebec population who aren't vaccinated.
"The reason we're all together is not to mount a revolution against vaccination," he said. "It depends on the person — we are a group of about five or six hundred people and some are vaccinated among the group and others are not."
Dr. Gaston De Serres, a medical epidemiologist at the Institut national de sante publique du Quebec, said measles is very contagious and spreads quickly in a setting where people are not immunized.
"The first cases occurred in large families who initially had one or two cases and now all the siblings are infected," De Serres said. "Still, we have a limited number of families that are affected and all the cases are within that religious group and there's no spillover into the rest of the population."
This year, there have also been 18 cases of measles confirmed in Ontario, all in the Toronto and Niagara regions, and one in Manitoba.
The Quebec cases are all linked to the Disneyland outbreak, which as of March 6 had sparked 142 infections in seven states, according to the U.S. Centers for Disease Control.
Measles is highly contagious and causes fever, a distinctive red rash and a runny nose. While most people who become infected will only experience an unpleasant illness, the disease can have more serious complications in some cases, particularly in young children.
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