Christmas Day shambles at NHS helpline as '17-year-olds with barely any training left to answer phones' Whistleblower claims patients were left waiting for 20 minutes Young, inexperienced call centre staff struggled to cope with flood of calls The worker fears people with serious conditions were kept waiting Patients who rang the under-fire NHS 111 helpline over Christmas faced 20 minute waits while inexperienced operators - some just teenagers - struggled to cope with the sheer volume of calls, it was claimed today. There are fears that people with serious conditions 'slipped through the net' as call centres were deluged with patients over the festive season, it has been reported. A shortfall in staff meant operators aged just 17 with no relevant qualifications and just a month or two of training were expected to deal with potentially serious medical enquiries, it is alleged. An NHS whistleblower says 111 call centre staff (not pictured) were forced to leave patients waiting for 20 minutes as demand for the service soared over Christmas. The call centre operators in West Yorkshire raised colour-coded cards when they couldn't cope or did not know what to do, says a whistleblower, speaking to the Sunday Mirror. The worker said it was impossible for staff to answer the calls in time because of a spike in calls as demand for the service rises significantly over Christmas because of poor weather and uncertainty over the availability of medical services. Many callers simply hung up in frustration and headed to hospital anyway - placing pressure on medical services that NHS 111 was set up to alleviate. Some of the call centre staff were 17-year-olds with no relevant qualifications, it has been reported She added that the lack of clinical staff and on-duty GPs over Christmas also placed a strain on the service - some of those who stayed on the line faced a wait of more than 24 hours for a call back from a doctor. 'I was sat there in my headphones and and the screen in front of me was lit up like a Christmas tree with all the callers trying to get through,' she said. You wonder how many people with serious conditions slipped through the net. Long waits may have caused the caller's condition to deteriorate, she added, and new staff were not experienced enough to make judgement calls on what could be serious medical complaints. NHS 111 was rolled out this spring to give patients round-the-clock medical advice over the phone. The Government launched the helpline to replace GP out-of-hours numbers and the NHS Direct helpline. But the study concluded that in its first year, NHS 111 â€˜did not deliver the expected system benefits of reducing calls to the 999 ambulance service or shifting patients to urgent rather than emergency careâ€™. It is manned by call centre workers with just six weeks' training - who according to experts have been sending patients to A&E and calling out ambulances unnecessarily. Concerns have also been raised that patients who are not put through to a doctor or nurse hang up in frustration and end up going to casualty anyway. She added: 'Anyone with a bit of experience could tell the difference between, say indigestion or a heart attack. But these young kids didn't have that.' Paramedics were also hampered by rules which state that they could only leave a patient when a doctor allowed them to. As a result, jobs that normally take 20 minutes dragged on for more than an hour as medical staff waited for the green light from a GP. A statement from NHS England said it is 'closely monitoring the NHS 111 service'. It added: 'We can assure the public the service has held up well over the majority of the country over the very busy Christmas period and continues to do so in this period between Christmas and new year. The service has been able to meet the 95 per cent standard of calls answered promptly (within 60 seconds). This is thanks to the careful planning and extra staff brought in by the providers of the service. Yorkshire Ambulance Service, which operates the call centre the whistleblower works at, was not available for comment. Last month it was reported that NHS 111 helpline could be putting even more pressure on A&E units - despite being set up to reduce the number of patients turning up at casualty. A government-commissioned study found that in some areas the helpline led to an extra 400 patients and an additional 600 ambulance call-outs every month. Research by academics at the University of Sheffield, published in the British Medical Journal, looked at four areas where the helpline was introduced in 2011 and compared the number of patients going to A&E and ambulance call-outs a year later. They found in Nottingham, it led to an extra 400 patients showing up in A&E every month â€" an increase of 6 per cent â€" while there was a 5 per cent rise in Luton, which worked out as an additional 200 patients a month. The study also found that in Durham and Darlington nearly 1,000 extra patients turned up in urgent care centres every month, an increase of 8 per cent compared to the previous year. Professor Sir Bruce Keogh, the medical director of NHS England, said he intends to beef-up the NHS 111 helpline by hiring more doctors and nurses. He also announced a major shake-up of A&E departments, introducing the idea of a two-tier system. This would see about half of A&Es dealing with heart attacks, strokes and serious injuries with the remainder treating less critical patients. The plans will also see GPs offering more same-day appointments and opening their surgeries at evenings and weekends to reduce the need for patients to go to A&E. But the idea has already run into controversy, with critics saying the new system will only end up confusing patients. Labourâ€™s health spokesman Andy Burnham said: â€˜2013 has been the worst year in a decade in A&E. It is a crisis of David Cameronâ€™s own making. â€˜It is clear that his decision to scrap NHS Direct and replace nurses with call handlers has added to the pressure on A&E.â€™