Infectious Disease Trends in Ontario

The Infectious Disease Trends in Ontario interactive tool provides 10 years of analyzed data on diseases of public health significance in Ontario. Data are collected by the public health units primarily from clinicians, laboratories and hospitals and then analyzed by PHO.

This tool can help with surveillance, as well as inform program planning and policy. Search, customize and export information from interactive maps, graphs and tables according to your needs. You can also sort the data by public health unit or local health integration network (LHIN), as well as demographics.

Case counts presented in this tool include only the confirmed classification for all diseases, except for the following diseases where both confirmed and probable cases are included in the total counts: amebiasis, Lyme disease, mumps, pertussis, invasive meningococcal disease (IMD), invasive Haemophilus influenzae (Hi) disease all types, and West Nile virus (WNV) illness. Case classifications are specified in the provincial surveillance case definitions outlined in Appendix 1 of the Infectious Diseases Protocol.

Due to the impact of the COVID-19 pandemic on the public health and health care sectors, there may be limitations with the 2019, 2020, 2021 and 2022 data presented in this tool. Trends should be interpreted with caution.

Previous Summaries

Factors Affecting Reportable Diseases in Ontario, 1991-2016

Interested in changes to reportable diseases status in Ontario? This report documents major changes to reportable disease status, case definitions, as well as outbreaks and changes to laboratory testing, which impacted reportable disease trends in Ontario from 1991 to 2016.