Two rural hospitals in Listowel and Wingham, Ont., have regained access to their computer systems after a ransomware attack last month.

The Listowel Wingham Hospitals Alliance says it has investigated and is confident there was no unauthorized access to anyone's personal information, personal health information or other sensitive information.

"No contact was made with the hackers. No ransom amount was requested, nor did we pay a ransom," the alliance said.

The situation was dubbed Code Grey because that's the term used to describe the loss or failure of hospital infrastructure, the alliance said. It began on Sept. 25 when administration discovered a "cyber security incident."

The alliance said it had to temporarily lock down its computer systems, which also impacted connection to regional and provincial information systems.

The emergency departments in both Listowel and Wingham remained open and operational, but local doctors offices were also impacted and some patients experienced a delay in care, the alliance said. Medical staff had to use paper documents and some offices didn't have access to patient files or lists.

As well, two days of chemotherapy treatment at the Wingham hospital were delayed, a some patients had diagnostic testing or specialist appointments deferred.

As of Friday, the hospitals alliance said the system is back online "in a manner that continues to protect the security and integrity of information."

The alliance said the community has been "incredibly understanding" during the month it took to get the situation sorted and showed "extraordinary patience."

Hospital staff and physicians were also "exceptionally resilient and innovative" during the past month, the alliance said.

The hospitals' ransomware attack came just days after similar cyberattacks at the city of Woodstock and the Woodstock Police Service.

Stratford was hit by a ransomware attack in April and paid around $75,000 in Bitcoin to restore access to its information systems. The city has submitted a cyber-insurance claim to offset the costs of the attack and expects to pay a $15,000 deductible.