Measles Exposure in Canada: What to Do Now, Updated November 8, 2026

Information checked: November 8, 2026, at 20:04 UTC.

If you think you have been exposed to measles, contact your local public health unit or a health care provider immediately—even if you feel well. If you are unvaccinated or have never had measles, isolate while you seek guidance. Preventive treatment is time-sensitive: for eligible people, a measles vaccine can help within 72 hours of exposure, while immunoglobulin may help within six days.

Canada’s Public Health Agency announced on October 19 that a multi-jurisdictional outbreak was over, but said travel-related cases are expected to continue. An exposure alert or a possible contact still deserves prompt attention; it does not mean that measles is spreading in every Canadian community. Read the Public Health Agency of Canada announcement.

Destaques

• Call public health or a health care provider promptly and tell them when and where the exposure may have happened.
• Do not wait for a rash: preventive options work within limited time windows and depend on your circumstances.
• If symptoms develop, isolate and call before visiting a clinic or emergency department.
• Have your vaccination records ready, but do not delay the call while searching for them.

What should you do first after a possible measles exposure?

Move away from others if you are unvaccinated or have not had measles, and call your local public health unit or health care provider immediately. If you are unsure about your immunity, call for advice rather than assuming you are protected. Public health can assess the exposure and tell you whether you need to stay home, receive preventive treatment, or take other precautions.

When you call, share the date and location of the possible exposure, any symptoms, and what you know about your measles vaccination or previous infection. Mention immediately if the exposed person is an infant, is pregnant, or has a weakened immune system. These details affect the advice and treatment offered.

Check your province or territory’s public health website for its local contact information and exposure notices. An exposure notice may identify a place and time when someone with measles was present. Compare those details with your own movements, but do not wait for a public notice if a health professional or another reliable source has already alerted you to a possible exposure.

Can a vaccine or other treatment help after exposure?

Sometimes. The Canadian Immunization Guide recommends assessment and prompt post-exposure prevention for people who are not expected to be immune. The choice depends on factors including age, vaccination history, pregnancy, immune status, and the time since exposure.

• Within 72 hours: A measles-containing vaccine can prevent measles after exposure in eligible people when given as soon as possible within this window.
• Within six days: Immunoglobulin, a preparation containing protective antibodies, may prevent measles or make it less severe for eligible people. It is especially relevant to certain infants, pregnant people, and people with weakened immune systems.

These are deadlines for assessment and treatment, not reasons to wait. A clinician or public health professional must decide which option is appropriate. Immunoglobulin provides short-term protection and can affect the timing of a later vaccine. Prevention after exposure does not guarantee that infection will be avoided.

If more than 72 hours have passed, still call. Some people may qualify for immunoglobulin within six days, and starting or completing vaccination can help protect against future exposures even when a vaccine is no longer known to prevent disease from this particular exposure. An early dose given to an infant before their first birthday does not replace the two doses recommended after 12 months of age for long-term protection.

Do you need to isolate after a measles exposure?

That depends on your immunity, symptoms, and public health advice. Federal guidance says people who believe they were exposed and have not been vaccinated or had measles should isolate and contact a health care provider or local public health department immediately. Public health may also direct susceptible contacts to stay home from school, childcare, work, travel, or gatherings for a specified period.

Follow the instructions given for your situation, including when you can return to normal activities. If you have documentation of two doses of a measles-containing vaccine, share it with the person assessing you. Two doses offer strong protection, but report symptoms or concerns even if you are vaccinated. If your records are missing, public health or your provider can help assess what to do next.

What if you develop symptoms or need medical care?

Isolate at home away from others and contact a health care provider immediately. Early symptoms can include fever, cough, runny nose, and red eyes; a rash may follow. You do not need to wait for the rash to appear before calling.

Before going to a clinic, hospital, or other health care facility, call ahead and say that you may have measles. Staff can arrange precautions to protect other patients and workers. Canada’s measles care guidance also recommends wearing a well-fitting respirator such as an N95; if one is unavailable, wear a well-fitting medical mask. If you need emergency assistance, call 911 and tell the dispatcher about the possible measles exposure.

Measles spreads through the air, and a person can transmit it before a rash appears. That is why advance notice and following public health instructions matter even when an exposure seemed brief. A provider can advise how to reduce exposure to other household members and arrange testing if needed.

What happens next in Canada?

Public health officials investigate cases and contacts, while provinces and territories lead local responses. The federal agency said the outbreak that began in October 2024 ended after more than two months without a reported case linked to it. Its end did not automatically restore Canada’s measles elimination status, and it does not rule out future imported cases or local outbreaks.

For an individual, the next step is to keep the instructions from the professional who assessed the exposure and report any new symptoms promptly. For current local alerts, use your provincial, territorial, or local public health authority; circumstances and directions can differ by location.

Frequently asked questions

Should I call if I have had two measles vaccine doses?

Yes. Two doses provide strong protection, but a health care provider or public health unit can assess your specific exposure and advise you, especially if you develop symptoms or have a weakened immune system.

What if I cannot find my vaccination record?

Call anyway and explain what you know. A provider or public health unit can help assess your history and may suggest ways to retrieve records or arrange appropriate vaccination.

Can I go to work or school while I feel well?

Ask public health or your provider. Whether you need to stay home depends on your immunity and the exposure; feeling well alone does not settle the question.