---
title: Ontario Health Agency Hid Cyberattack from Patients for Months
description: Ontario Health atHome delayed notifying up to 200,000 patients about a major cyberattack, only going public after pressure. Sensitive medical data was compromised in the breach.
canonical_url: https://codekeeper.co/ticker/ontario-health-agency-hid-cyberattack-from-patients
---

[Cyberattacks](https://codekeeper.co/ticker/tag/cyberattacks)

# Ontario Health Agency Hid Cyberattack from Patients for Months

Ontario Health atHome delayed notifying up to 200,000 patients about a major cyberattack, only going public after pressure. Sensitive medical data was compromised in the breach.

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By Content Team Jul 31, 2025

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Ontario Health atHome knew about a massive cyberattack affecting up to 200,000 patients as early as April 14 but didn't tell the public until June 27. The breach at vendor Ontario Medical Supply actually happened in March, compromising patient names, addresses, medical diagnoses, and prescription data. The agency waited six weeks to notify Ontario's privacy commissioner and only informed patients after Liberal MPP Adil Shamji forced their hand by revealing the incident publicly. Health Minister Sylvia Jones then ordered the agency to contact affected patients. Critics call the delay "deception" and "incompetence," warning the stolen data could enable identity theft and blackmail. Source: [Global News](https://globalnews.ca/news/11308121/ontario-health-athome-cyberattack-notified/)

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