Five additional health systems were notified that hundreds of thousands of patients may have had their information compromised in the ransomware attack on Health Alliance Plan and Blue Cross Blue Shield of Michigan, Detroit Free Press reports.
In addition to HAP and BCBS, Grand Blanc, Mich.-based McLaren Healthcare, Three Rivers (Mich.) Health, North Ottawa Community Health System in Grand Haven, Mich., Warren (Pa.) General Hospital and UPMC Kane were affected by the data breach.
Collectively, the total number of patients affected by the breach is estimated to be in the hundreds of thousands, Wolverine Solutions Group President Darryl English told Detroit Free Press.
WSG, the medical billing vendor for the healthcare organizations, experienced a ransomware attack Sept. 23, which left the company locked out of its servers and workstations. The attack may have exposed individuals' names, addresses, dates of birth, member identification numbers, healthcare provider names, patient identification numbers and claim information.
WSG's ongoing investigation determined the affected records were encrypted. The company is sending letters to notify individuals who may have been affected by the incident and is also providing them free identity protection and credit monitoring services throughout the next year.