The B.C. Centre for Disease Control says 29 people in B.C. have come down with measles in recent weeks. (CBC)

Unvaccinated students are being sent home from school because of the growing measles outbreak in Vancouver, and that has at least one parent concerned that the policy is unfair.

In recent weeks, eight students in six Vancouver schools have come down with measles, according to Vancouver Coastal Health medical health officer Dr. John Carsley.

When measles is reported in a school, health officials check that all other children and staff have had vaccinations. Those who haven't can be given one if it's detected quickly, said Carsely.

But if they can't get a vaccination in time, unvaccinated children will be sent home for 21 days, he said.

Daughter sent home for three weeks

That's the situation Tania Conley found her daughter in. Even though her daughter isn't sick, the Grade 7 student was sent home for three weeks because a case of measles was detected in her classroom.

Conley said she did not vaccinate her daughter because she had concerns she might have an allergic reaction to the egg products in the vaccine, but she was planning to have her vaccinated when she got older.

"I think every parent, whatever decision they make, it's always because they love their kids, and they want to do what's best. It's not a right or wrong issue," said Conley.

But Conley said the length of the quarantine is too long because she believes measles is only infectious for up to 14 days.

She is also particularly concerned because her daughter had been looking forward to taking part in an upcoming student exchange.

"The timing is just horrible, because it is right when the children are involved in a student exchange with a group of students form Quebec. Our kids had gone to Quebec in February, now it's their turn to host them in B.C.," said Conley.

Risk to others is clear-cut

But the Vancouver Coastal Health authority says the issue is clear-cut: measles normally has an incubation period of two weeks, but it can have an incubation of up to 20 days.

Because even vaccinated children can get sick, a three-week quarantine is necessary to protect all the students, said Carsley

"The policy here in B.C. is very conservative because we want to be sure that somebody who might fall sick, falls sick, and doesn't come back to school if they are sick, and perpetuate the outbreak," said Carsley.

"Usually nobody gets infected because there aren't that many people that can get measles anymore. Occasionally there will be other cases. This is the first time certainly that we have had any sustained transmission for several years in B.C.," he said.

Conley vaccinated her child on Monday, hoping the school would then allow her to attend class this week.

But the district said the vaccination came too late and Conley's daughter will just have to stay home.

Outbreak continues to spread

A total of 29 people across B.C. have been diagnosed with measles since the outbreak began last month, with 10 cases in the Fraser Valley, 14 cases in Metro Vancouver, four cases in the Interior and one case on Vancouver Island.

"It's very unusual because of our vaccination programs. Measles has pretty well disappeared as a disease in North America entirely," said Carsley.

Most children are immunized when they receive two dose of a combined measles, mumps rubella vaccine. But for unvaccinated children, the contagion rate is close to 100 per cent, and they don't have to be in same room as an infected person to catch the disease, he said.

Measles starts with a runny nose and fever, turns into a rash, and can lead to ear infections, pneumonia and even inflammation of the brain. But there's a very high health risk for measles, say health officials. One in 1,000 will get encephalitis, or risk permanent brain damage, and one in 3,000 will die.