Cook County Health and Hospitals System, the covered entity (CE), reported that its business associate (BA) experienced a ransomware attack that compromised the protected health information (PHI) of 1,248,546 individuals. The PHI involved included names, addresses, dates of birth, Social Security numbers, diagnoses, and other treatment information. The CE notified HHS, affected individuals, and the media. In response to the breach, the CE terminated its business relationship with the BA.
