- 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.
Smallpox
Smallpox is a contagious disease caused by the variola virus. The disease was eliminated globally as a result of vaccination, with the last naturally occurring case occurring in 1977. Smallpox was transmitted from person-to-person through contact with smallpox sores and through coughing or sneezing.
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 smallpox by year
More information about smallpox
Merck Manual
Report to the Health Unit immediately by fax (705-482-0670) and phone at 705-474-1400 or toll free at 1-800-563-2808, ext. 5229 if smallpox 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.
After hours, weekends, and holidays, call 705-474-1400 then press 0 to speak with the Answering Service. The on-call CDC Public Health Nurse will get back to you as soon as possible.
Should one go to childcare, school, or work if they have smallpox?
Contact the Health Unit.
Exclusion is required, but the length is assessed on an individual case basis.
Smallpox is 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
Public Health Ontario: Smallpox
Merck Manual Professional Version: Smallpox
Infectious Disease Protocol, Appendix 1: Smallpox and other Orthopoaxviruses
Public Health Agency of Canada: Smallpox and Mpox Vaccines: Canadian Immunization Guide
Public Health Agency of Canada Pathogen Safety Data Sheets: Infectious Substances - Variola Virus
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: February 2025, by CDC