Measles

Infectious Diseases

To view current locations where measles exposures may have occurred please visit our measles exposure page.

Measles prevention

The best protection against measles is vaccination with two doses of a measles-containing vaccine, which are almost 100 percent effective at preventing infection.

  • Two doses of measles vaccine are given to children after their first birthday. Measles vaccine is given in combination with other vaccines.
    • The first dose is MMR (measles, mumps, rubella) vaccine, given at 12 months of age.
    • The second dose is MMVR (measles, mumps, rubella, varicella) vaccine, given between four to six years of age, preferably before school entry.
  • In light of recent measles outbreaks in Ontario and broader concerns about child and maternal immunizations, SickKids is pleased to offer the Immunization InfoLine, a free source of information for all things related to immunization. This service is available in any language, and anyone in Ontario can easily book an appointment online.
  • Some adults may have received only one dose of measles vaccine. A second dose of MMR vaccine is recommended for anyone born in 1970 or later.
  • Workers in healthcare, childcare, school, or post-secondary and military settings are strongly encouraged to have two doses of measles-containing vaccine or evidence of immunity.

Measles vaccine should not be given to pregnant women. Individuals with weakened immune systems are recommended to consult their health-care provider as they may not be able to receive measles-containing vaccines.

Important immunization information for travellers

Anyone who is not fully vaccinated against measles is at risk of being infected when travelling outside of Canada. To be fully vaccinated:

  • Adults 18 years of age and older who have previously received one dose of MMR should receive a second dose if they are health-care workers, post-secondary students, planning to travel to areas with increased measles transmission or based on health-care provider’s clinical judgement.
  • Children four years of age and older should have received two doses of a measles-containing vaccine.
  • Children are not routinely provided a second measles-containing vaccine until after their fourth birthday. However, if travelling to a high-risk area, those who have received one dose of measles-containing vaccine, and are 13 months to four years of age, could receive a second dose of measles-containing vaccine earlier than when it is routinely provided. A health-care provider can advise on the best approach for your child.
  • Infants are not routinely immunized for measles until after their first birthday. However, if travelling to a high-risk area, infants six to 12 months of age should receive a dose of measles-containing vaccine. Two additional doses of measles-containing vaccine are still required, one on or after the first birthday and the second between four to six years of age. A health-care provider can advise on the best approach for your child.

If needed, measles vaccination should be given at least two weeks before travelling. However, there are still benefits if given less than two weeks before departure.

Important information for children in elementary and secondary school with vaccine exemptions

If there is a case of measles at school, children with valid exemptions under the Immunization of School Pupils Act (ISPA) will be excluded from school if they do not have two valid doses of measles-containing vaccine (e.g., MMR or MMRV) past 12 months of age.

Children may return to school when they meet one of the following criteria:

  • Twenty one days have passed since their last exposure to measles and there are no further cases in the school.
  • A measles outbreak is declared over.
  • There is proof of lab confirmed immunity.
  • They have received their second dose of measles-containing vaccine.

If you have questions and would like to speak to a member of our immunization team, call your closest Southeast Public Health office:

Frequently asked questions

If you shared a room or airspace with someone who has measles for any length of time (and for up to two hours after the person left the space):

  • Check vaccination records to ensure protection from measles.
    • Immunity requires two doses of a measles vaccine or proof of immunity through a laboratory test. If you are unsure of your vaccination status:
      • Check your record (please note that public health may not have records for anyone born in 1985 or earlier).
      • Call your health-care provider.
      • Call your closest Southeast Public Health’s office:
    • Most individuals born before 1970 are generally presumed to have acquired immunity due to infection in their childhood, as high levels of measles were circulating before 1970.
  • If you are not vaccinated or have had only one dose of measles vaccine you should monitor for symptoms, isolate at home for 21 days following your exposure and seek vaccination through Southeast Public Health or primary care clinics.
    • Call before visiting a health-care setting and notify them of your recent measles exposure. This helps protect others and allows health-care providers to prepare for your visit.
    • Monitor for symptoms until 21 DAYS following your exposure date (even if you are vaccinated). Symptoms of measles start seven to 21 days after exposure and may include:
      • high fever, cough, runny nose
      • red, watery eyes (pink eye or conjunctivitis)
      • red blotchy rash
  • If you develop symptoms, stay home and do not go to work, school, daycare and public settings. Call your health-care provider before visiting to let them know you may have measles and need special precautions. You may also call your closest Southeast Public Health office:
  • Please contact Southeast Public Health immediately if you fall into any of the following categories:
    • Were with an infant under 12 months of age during exposure.
    • Are pregnant and unvaccinated or unsure of your immunity to measles.
    • Are immunocompromised.

You may be eligible for preventive treatment. Call Southeast Public Health:

  • Stay home. Don’t allow others to visit for at least four days after the rash starts.
  • Call your closest Southeast Public Health office:
  • Contact your health-care provider by phone. If you need to visit a health-care provider, call before you arrive. Tell the health care provider about your measles symptoms so other patients can be protected. Put on a mask before you enter.
  • If your health-care provider suspects you have measles, they should notify Southeast Public Health.

There is no treatment for measles. Supportive measures can help to relieve symptoms.

Measles is a very contagious viral infection that can cause serious disease. Over 90 percent of people who are not immune will become infected if they are exposed to the virus.

Measles can result in complications including ear infections, pneumonia, deafness, and brain damage. Rarely, death can occur.

Children less than five years of age, pregnant women, and people with weakened immune systems are at higher risk of complications from measles.

Measles is a virus that spreads easily through the air. It is passed in tiny droplets when an infected person coughs, sneezes, or breathes. It can survive in the air for up to two hours.

A person with measles can spread the infection to others four days before to four days after the rash starts.

The first symptoms of measles are:

  • fever, runny nose, and cough.
  • eyes that are red, runny, and sensitive to light.

Three to seven days later, a red, blotchy rash appears. The rash begins on the face, spreads over the body and then down the arms and legs.

Symptoms usually appear around 10 days after a person has been exposed to the virus but can start anywhere from seven to 21 days. The rash usually develops 14 days after exposure.

A health-care provider may suspect measles based on your symptoms. They may ask you about any contact or exposures to measles and may ask if you are immune to measles (through vaccination or previous infection). If your health-care provider suspects measles, they will collect samples for testing which can include:

  • a swab from your nose or throat
  • a urine test
  • a blood test

Any tests that show the measles virus are automatically reported to Public Health.

There are no specific treatments for measles infections. Your health-care provider may recommend medications to help you feel more comfortable, encourage you to drink plenty of fluids and rest. If your symptoms worsen, you may need to seek urgent medical care.

People with measles are contagious starting four days before their rash starts and stay contagious until four days after their rash starts. People with measles should self-isolate from all public places and avoid contact with others while they are contagious.