Pauline Cafferkey enters an isolation tent before boarding a RAF Hercules at Glasgow Airport on February 23Credit:Jeff J Mitchell/Getty Images A nurse who has repeatedly fallen seriously ill after contracting the Ebola virus two years ago has been taken to hospital again, under police escort.Pauline Cafferkey was said to be in a stable condition after she was hospitalised for the fourth time since contracting the deadly viral haemorrhagic fever while working for a charity in Sierra Leone.Doctors said the 40-year-old was undergoing routine monitoring at the infectious disease department of Glasgow’s Queen Elizabeth University Hospital. Last month, Ms Cafferkey was cleared of misconduct over her return to the UK with the virus.She was accused by the Nursing and Midwifery Council of allowing an incorrect temperature to be recorded in a “chaotic” screening centre in Heathrow on her return from Sierra Leone in late 2014.Ms Cafferkey said she would never have knowingly put anyone in danger and an independent panel found three charges against her were not proven and her fitness to practise was not affected.It ruled her judgement at the airport in December 2014 had been so impaired by the developing illness that she could not be found guilty of misconduct. Ms Cafferkey was discharged in January 2015, with doctors saying she had completely recovered and was not infectious in any way.However, she was readmitted to hospital twice – in October 2015 and February 2016 – after suffering complications linked to the disease, at one stage falling critically ill.Nicola Sturgeon, first minister, said: “Sending my very best wishes to Pauline Cafferkey. She has already suffered way too much – & all for trying to help others. Thoughts with her.” Officials declined to say if the disease had recurred, or whether she was suffering from other complications, but said there was no risk to the wider public.The nurse was infected with the virus while working as a volunteer for Save The Children during the outbreak that killed more than 11,000 people across Guinea, Liberia and Sierra Leone from 2014.On her return at the end of 2014, she was quickly struck down and was taken by military transport plane to the Royal Free Hospital in London. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.