Montreal public health officials have issued a warning after a new case of measles was identified in a child who visited Montreal–Trudeau International Airport and a hospital emergency department while infectious.
According to Quebec public health authorities, the child was present in the international arrivals area of Montreal–Trudeau International Airport on Friday, October 9, and at the emergency department of CHU Sainte-Justine on Saturday, October 10. People who visited these locations during the specified periods may have been exposed to the highly contagious virus. The airport exposure occurred between 6:26 p.m. and 9:56 p.m. on October 9. At CHU Sainte-Justine, the possible exposure period was between 6 a.m. and 11:52 a.m. on October 10. Health officials have advised people who were present at either location during those hours to monitor themselves for symptoms. Those potentially exposed at the airport should watch for symptoms until October 30, while people who may have been exposed at the hospital should continue monitoring their health until October 31. The dates reflect the public health authority’s recommended monitoring periods following the reported exposure. Measles is a highly contagious viral disease that spreads through the air when an infected person breathes, coughs or sneezes. The virus can remain in the air for a period after an infected person has left an area, making exposure possible even without direct contact. Early symptoms typically include fever, cough, a runny nose and red or watery eyes. A rash usually develops several days later, often beginning on the face before spreading to other parts of the body. Symptoms can appear days after exposure, which is why health authorities are urging potentially affected individuals to remain alert. Although many people recover, measles can lead to serious complications, including pneumonia and inflammation of the brain. Infants, pregnant people who are not immune and individuals with weakened immune systems face a greater risk of severe illness. Public health officials are advising people who may have been exposed to check their measles vaccination status. Individuals who are not considered protected may need vaccination or other preventive treatment, depending on their circumstances and how recently the exposure occurred. Anyone who believes they may have been exposed should contact a healthcare professional or public health service promptly for advice. People who develop symptoms and suspect measles should contact a healthcare provider before visiting a clinic or hospital in person. Calling ahead allows healthcare staff to take precautions and reduce the risk of exposing other patients and staff to the virus. The new case comes amid continued measles activity in Canada. Federal surveillance data reported 1,121 cases across the country as of September 26, 2026. Canada lost its measles elimination status in November 2025 after the virus continued to circulate for more than a year.
Quebec’s most recent major measles outbreak ended in August, after 28 cases were reported. However, health officials continue to investigate individual cases and identify locations where further transmission may have occurred. Authorities are also reminding the public that vaccination remains the most effective way to prevent measles. People who are unsure whether they are adequately immunized should consult their vaccination records or contact a healthcare professional. Public health officials are continuing to monitor the situation and may update the list of exposure locations as more information becomes available. Residents and travellers who visited the airport or hospital during the specified times are encouraged to follow the official guidance and seek medical advice if they are concerned about possible exposure.