NHS England has issued a warning about potential "delays" as the health service attempts to recover from Friday's worldwide IT outage. Despite this, patients with appointments scheduled for this week have been advised to "should continue to attend unless told not to".

This follows a cautionary statement from the British Medical Association (BMA) on Sunday, stating that normal GP services "cannot be resumed immediately" due to the "considerable backlog" caused by the outage. The doctors' trade union emphasised that GPs would require time to catch up on the work lost over the weekend and urged NHS England to communicate this clearly to patients.

The BMA also revealed that its GP committee is in ongoing discussions with NHS England and EMIS, the patient record system supplier, to establish a more robust IT backup system to prevent a recurrence of such a "disaster". The global disruption was triggered by a faulty update rolled out by cybersecurity firm CrowdStrike, which resulted in numerous services going offline worldwide on Friday, leading to flight and train cancellations and severely impacting some healthcare systems.

CrowdStrike's CEO, George Kurtz, announced that a fix had been deployed for the bug in the update, which affected devices running the Microsoft Windows operating system. However, he warned it would take "some time" for systems to be fully restored.

In England, several GP surgeries reported being unable to book appointments or access patient records on Friday when their EMIS system went down, reports the Manchester Evening News.

An NHS spokesperson reassured: "Systems are now back online, and patients with an NHS appointment this week should continue to attend unless told not to. Thanks to the hard work of NHS staff throughout this incident we are hoping to keep further disruption to a minimum, however there still may be some delays as services recover, particularly with GPs needing to rebook appointments, so please bear with us."

"It's important that patients attend appointments as normal unless told otherwise. You can contact your GP in the usual way, or use your local pharmacy, NHS 111 online or call 111 for urgent health advice."

Offering a chilling glimpse into the magnitude of the problem, Dr David Wrigley, deputy chairman of GPC England, the representative body for GPs at the BMA exclaimed: "Friday was one of the toughest single days in recent times for GPs across England. Without a clinical IT system many were forced to return to pen and paper to be able to serve their patients."

"While GPs and their teams worked hard to look after as many as they could, without access to the information they needed much of the work has had to be shifted into the coming week. GPs have been pulling out all the stops this weekend to deal with the effects of Friday's catastrophic loss of service and, as their IT systems come back online, we thank them and their staff for their hard work under exceptionally trying circumstances."

"We also thank patients for bearing with general practice in this unprecedented situation."

Dr Wrigley has voiced his concerns, stating: "The temporary loss of the EMIS patient record system has meant a considerable backlog. Even if we could guarantee it could be fully fixed on Monday, GPs would still need time to catch up from lost work over the weekend, and NHSE (National Health Service England) should make clear to patients that normal service cannot be resumed immediately."

He further stressed the importance of ongoing discussions for improvement: "The BMA's GP committee will continue our dialogue with both EMIS and NHSE, both to make sure that the coming week can be used to recover as quickly as possible and to urgently work on securing a better system of IT back-up so that this disaster is not repeated in future."