A passenger with the infectious virus, who was contagious, reportedly took a flight from Las Vegas to Montreal last week.

Montreal's Public Health authority says the MUHC has done an "absolutely rigorous and exemplary handling of the situation," after a hospital employee showed up to work while contagious with measles. 

Santé Montréal said a patient with a confirmed case of measles travelled by air from Minsk, Belarus, to Montreal on Jan. 27.