HEALTH bosses have praised the skills of its IT staff for helping save Bolton from the largest cyber attack in NHS history.

The Bolton NHS Foundation Trust avoided coming to a standstill earlier this month when computers hackers caused worldwide chaos.

Forty hospital trust became infected by a “ransomware” attack demanding payment to regain access to vital medical records on May 12.

While Bolton was not affected, the trust put additional IT security measures and restrictions in as a precaution.

Fortunately no appointments or operations had been cancelled due to the attack.

At Thursdays meeting of trust board members, chairman David Wakefield praised the IT department and the work of chief technology officer Brett Walmsley.

He said: "We asked the cyber attack. That was only down to the professionalism and due diligence of our IT team.

"I may have been one of the biggest critics of our IT team in the past but on Thursday I thought thank heavens these guys are on top of their game!

"Brett has been highlighted as the key expert and this has been recognised across Greater Manchester. He has mow been asked to share his expertise with NHS organisations around the region."

Hospitals and GP surgeries in England and Scotland were among at least 16 health service organisations hit by a ransomware attack, using malware called Wanna Decryptor – with reports potentially dozens more were affected.

Operations and appointments were cancelled and ambulances diverted at up to 40 hospital trusts.

Staff were forced to revert to pen and paper and use their own mobiles after the attack affected key systems, including telephones.

Pictures posted on social media showed screens of NHS computers with images demanding payment of 300 US dollars worth of the online currency Bitcoin, threatening to delete files within seven days.

It is believes more than 300,000 computers were infected in more than 90 countries including Russia, Taiwan, Ukraine and India.

NHS Digital worked with the National Cyber Security Centre, the Department of Health and NHS England to support affected organisations and [rptect patient safety.

Within a week Microsoft issued a patch on to protect users from the ransomware while a cybersecurity researcher also appears to have accidentally discovered a a way of preventing it spreading by registering a domain name used by the malware.

Wanna Decryptor is a piece of malicious software that encrypts files on a user’s computer, blocking them from view and threatening to delete them unless a payment is made.

The virus is usually covertly installed on to computers by being hidden within innocent-looking emails containing links, which users are tricked into opening.