Two more hospitals have faced malware that froze their IT systems.
Prime Healthcare Services had its third hospital face malware in March when San Diego-based Alvarado Hospital Medical Center had an incident on March 31, according to the San Diego Union-Tribune.
Prime's Chino Valley Medical Center and Desert Valley Hospital also were affected by viruses but recovered their systems with minimal disruption and didn't to pay ransom.
Alvarado took "extraordinary steps to protect and expeditiously find a resolution to this disruption," according to a statement provided to the Union-Tribune, but offered few details except that patient and employee records had not been compromised.
Meanwhile, King's Daughters' Health in southeast Indiana proactively powered down all its computer systems after discovering that an employee's files had been infected with Locky ransomware virus, according to a WSCH radio report.
King's Daughters' Health officials told Indiana's WSCH radio that patient data were secure and had not been compromised. The hospital restarted its computer systems once it was safe to do so, according to information hospital officials provided to WSCH radio.
Ongoing staff education about evolving cyberthreats helped employees act quickly to contain the Locky virus once it was found, according to Linda Darnell, the hospital's senior director of IT.