Health Professionals Update – Vol. 18, No. 15
From:
Monica Hau, MD, MSc, CCFP, FRCPC
Associate Medical Officer of Health
In this issue:
- Update: Measles immunization letters to Peel students
- Chief Medical Officer of Health measles memo and FAQ
Key messages:
- Peel Public Health is sending measles immunization letters to students in grades 3 to 11 who have not provided updated immunization records.
- Due to increased demand, please maintain a one-month supply of measles vaccines.
- Please review the June 11, 2025 memo and FAQ from the Chief Medical Officer of Health on measles outbreak preparedness and response.
Update: Measles immunization letters to Peel students
Ontario continues to see a rise in measles cases. Since the multi-jurisdictional Ontario outbreak started in October 2024, Ontario has reported 2,083 connected measles cases, mostly in Southwestern Ontario (current as of June 10, 2025). Peel Region is not connected to the outbreak but has had a rise in travel related measles cases. Since 2025, Peel has had 8 confirmed measles cases. Typically, Peel has had 1-2 cases per year.
Under the Immunization of School Pupils Act (ISPA), measles vaccine records or valid exemptions for students must be reported to Peel Public Health (PPH). Beginning in late June 2025, PPH will be sending letters to Peel students in grades 3 to 11 who are not up to date with their measles vaccinations, according to Peel's records.
Parents/students will be instructed to either update their vaccine record (if they have had two doses of measles vaccine) or visit their primary care clinic or walk-in clinic to get vaccinated.
If a student brings you a letter:
1. Check the student’s immunization records:
- If the measles vaccines were already given, provide the parent/guardian with the vaccine date, product, and lot number.
- If not, administer the vaccine.
2. Remind parents to report the child’s immunizations online or by calling 905-799-7700 or 1-888-919-7800 (toll-free).
NOTE: Vaccines received outside Ontario are valid if there is written proof of vaccination at ages and intervals matching Ontario’s immunization schedule. Records must be in English or translated by the health professional, patient, or patient’s relative.
Preparing for letters - ordering measles vaccines
Increased demand for MMR/MMRV vaccines is expected over the summer months. Please maintain a one-month supply and place orders as needed.
Chief Medical Officer of Health measles memo and FAQ
On June 11, 2025, Dr. Kieran Moore, the Ontario Chief Medical Offer of Health, shared a memo to Ontario healthcare providers on measles outbreak preparedness and response. Ensuring high measles vaccine coverage is a key component of preventing and responding to measles outbreaks. Please review the memo and frequently asked questions and answers document for more information.
Contact us
The Health Professionals Update (HPU) is distributed to physician offices in Peel region via fax or email. Share this update with other health professionals in your clinic.
More information
Public Health Ontario (PHO) resources:
- Measles in Ontario (Epidemiological Summary)
- Routine and Outbreak-related Measles Immunization Schedules
- Measles: Information for Health Care Providers
Review past HPUs: https://peelregion.ca/business/health-professionals/health-professionals-updates
Recent measles HPUs:
- Health Professionals Update – Vol. 18, No. 13
- Health Professionals Update – Vol. 18, No. 11
- Health Professionals Update – Vol. 18, No. 7
- Health Professionals Update - Vol. 18, No. 6
Subscribe to HPU emails
For questions about this update, email healthprofessionals@peelregion.ca