A group of 39 Japanese high school students and their two chaperones have been quarantined at the Fairmont Vancouver Airport Hotel after one of the students was found to have the symptoms of measles.

They were about to board a flight at Vancouver International Airport on their way home when they were detained.

The students were part of a larger group from Japan that was isolated at a Banff hotel earlier this week after another teen came down with a suspected case of the disease after arriving in B.C. from Tokyo.

They returned to Vancouver for their flight home on Thursday when they were screened again, and another suspected case was found.

B.C. Provincial Health Officer Dr. Perry Kendall said those in the group who did not have immunity to the disease were detained.

"So in order not to expose other people in the plane on the 12-hour flight to possible measles exposure, Dr. David Butler-Jones took action under the Quarantine Act to isolate the case and quarantine the contacts."

Risk to B.C. not high

Kendall said the risk of measles spreading in B.C. is quite low because most British Columbians have either been vaccinated or have naturally acquired immunity to the disease.

"Not 100 per cent, but high enough that we have a good level of what is called 'herd immunity.' The few cases of measles that we've had imported into British Columbia have resulted in very small numbers of secondary cases.

"However if you are going to Tokyo, and you weren't sure about your MMR [measles, mumps, rubella] status it would be a good idea to check with your physician or to check your records to be sure that you've had two doses."

Kendall says there are about 700 reported cases of measles in the Tokyo area right now. He also noted that it is not standard in Japan for children to get a second MMR booster shot. 
 
Measles is a very contagious disease that is spread by airborne droplets when an infected person coughs or sneezes. The virus can survive for several hours in those droplets.

Symptoms of red measles, the most severe type, include a high fever; a harsh, dry cough; a runny nose; and red, puffy eyes that are sensitive to light. For part of the time, the patient has a rash.

It can take seven to 18 days after exposure for the disease to develop. There is no cure or treatment. Complications can lead to deafness, blindness or disability.