Health officials in Vancouver, Canada, have identified two new cases of measles linked to a March flight from Beijing carrying two infected passengers, CBC News reported Thursday. One of the cases was a Carver Christian High School student in Burnaby, just east of Vancouver, who was on the same flight as the travelers who tested positive for the highly contagious virus shortly after arriving in British Columbia. Information about the second case has not been released. However, it was confirmed that the person had also traveled on the Air China flight on March 21.

"It's one of those illnesses that can start a bit more suddenly,” Michelle Murti of Fraser Health told CBC. “People may just have a bit of fever, cough and runny nose, and not until a few days later does that typical measles rash come out.” The care group opened an immunization clinic at Carver Christian Thursday “as a precaution” and encouraged students and staff to get two doses of the measles vaccine, considered the most effective defense against the virus, which causes fever, rash and, in severe cases, hearing loss, brain damage or even death.

Last month, health officials in Vancouver alerted Air China Flight CA991 passengers that they may have been exposed to measles after two travelers were found to be infected with the virus. Neither of the passengers, both high school students, was fully immunized against the virus. They were likely exposed to measles around the same time, possibly while in China, health experts said.

Large measles epidemics were common in Canada prior to the immunization campaigns of the 1960s. The number of measles cases in the country today has dropped by more than 99 percent compared with 50 years ago, according to the public health group Immunize Canada.