Quebec's measles outbreak has expanded to include 11 confirmed cases, according to a Wednesday update from the province's health authority. This development marks a concerning escalation in the ongoing public health situation.
Hospital Exposure and Timeline
At least one person with measles visited the emergency department of Montreal Children's Hospital on Monday and Tuesday, as confirmed by Quebec's measles tracker website. The specific exposure times have been identified as:
- January 19, 2026, from 1 a.m. to 8:28 a.m.
- January 19, 2026, from 11 p.m. to 11:59 p.m.
- January 20, 2026, from midnight to 4:44 a.m.
Anyone who is not immune to the virus and was present at the Children's Hospital emergency department during these periods is considered to have been exposed to measles.
Outbreak Details and Geographic Spread
As of January 21, 2026, at 9 a.m., nine confirmed cases of measles have been reported in connection with the ongoing outbreak affecting multiple regions including Lanaudière, the Laurentians, Laval, and Montreal. Additionally, two confirmed cases of measles unrelated to the ongoing outbreak have been reported.
Quebec has been grappling with this measles outbreak since early December, occurring shortly after Canada lost its status as a measles-free country more than 25 years after eradicating the virus. Prior to December, the province had maintained a measles-free status since April.
Isolation Recommendations for Exposed Individuals
The Quebec Health Ministry has issued specific guidance for those who may have been exposed to measles. If you are not protected against measles, it is recommended that you isolate yourself at home from the fifth day following your first exposure to measles until the 14th day, inclusive, after your last exposure.
In practical terms, this means that individuals exposed on January 19 would need to monitor for symptoms and potentially isolate until February 9. The ministry emphasizes that vaccination remains the most effective method of protection against the measles virus.
Defining Immunity to Measles
According to health authorities, those considered immune to measles include:
- People born before 1970
- Individuals with a medical certificate confirming they had measles before January 1, 1996
- People with serology demonstrating the presence of antibodies against measles
- Those who have been vaccinated against the virus
The ministry states that if you're immune to measles, it is very unlikely you will contract the disease. However, even for those considered immune who were exposed to the virus, authorities recommend monitoring for symptoms as a precautionary measure.
Recent Developments and Context
Last week, a case unrelated to the ongoing outbreak was confirmed on a flight from Madrid to Montreal. The infected individual visited various locations around Greater Montreal, highlighting the potential for wider community transmission.
This outbreak represents a significant public health challenge for Quebec, particularly given Canada's recent loss of measles-free status after maintaining that designation for over a quarter century. Health officials continue to emphasize the importance of vaccination as the primary defense against measles transmission and complications.
