- Case counts (2016-2025), population estimates (2016-2023), & population projections (2024-2025): Public Health Ontario.
- Query: Case counts of reportable diseases by public health unit and year. Toronto, ON: Ontario Agency for Health Protection and Promotion; extracted on March 9, 2026.
Encephalitis
Encephalitis is acute inflammation of the brain, typically with spinal cord involvement, caused by a virus, bacteria, fungi, or protozoa. Encephalitis is usually a primary viral infection or it can be caused by an immune reaction (complication of certain viral infections or vaccinations).
Local Information
2025 Statistics
Incidence rate is the number of new cases of disease divided by the number of persons at risk for the disease during a particular time period.
Cases:
0*
Incidence rate per 100,000 in 2025: 0
*Includes confirmed cases in 2025.
Incidence rate per 100,000 of encephalitis by year
More Information about encephalitis
MSD Manual
Report to the Health Unit within one business day by fax (705-482-0670) or phone at 705-474-1400 or toll free at 1-800-563-2808, ext. 5229 if encephalitis is suspected or confirmed as per Ontario Regulation 135/18 and amendments under the Health Protection and Promotion Act, R.S.O., c.H.7.
Should one go to childcare, school, or work if they have encephalitis?
Contact the Health Unit. Exclusion depends on the causative agent.
Follow the direction of your healthcare provider, public health case manager, or occupational health at your workplace.
Note: Exclusion guidelines may differ for healthcare workers.
Some types of encephalitis are preventable by vaccination. Check your vaccination records or call the Vaccine Preventable Diseases program at 705-474-1400 or toll free at 1-800-563-2808, ext. 5252 to book a vaccination appointment or to obtain additional information.
Healthcare provider information
Infection prevention and control
Additional Precautions
Routine practices are recommended for hospitalized cases and additional precautions would depend on the causative organism.
Indications and limitations will be based on clinical presentation and be test specific due to the variability of the etiological organism. This should be discussed with the laboratory. For further information about human diagnostic testing, refer to the Public Health Ontario Laboratories.
Merck Manual - Professional Version
Ministry of Health - Ontario Public Health Standards
Contact our Communicable Disease Control (CDC) program at 705-474-1400 or toll free at 1-800-563-2808, ext. 5229, or by email to cdc@healthunit.ca for more information.
Last updated: Apr 2026, by CDC