The Illinois Department of Health has exposed the personal information of 700,000 people over the years

The US State Department of Health in Illinois has confirmed that a security breach over the years exposed the personal information of more than 700,000 people in the state.

The Illinois Department of Human Services (IDHS) said notice on January 2 that an internal map page containing resident information, used by government officials to help allocate public resources, was inadvertently exposed from April 2021 to September 2025, when the security breach was discovered.

Officials said the leaked data included information on 672,616 Medicaid and Medicare Savings Program recipients. The data included their addresses, case numbers, and demographics – but not individual names.

The identified data also included names, addresses, case statistics, and other information about 32,401 individuals who received treatment from the Department of Rehabilitation Services.

IDHS said it could not determine if anyone had seen the publicly displayed maps during the four years they were available online.