Queen Elizabeth II was left feeling "very tired and exhausted" when she had Covid-19.The 95-year-old tested positive for coronavirus in February and Buckingham Palace officials said she experienced "mild cold-like symptoms" and was able to carry out light duties while she self-isolated at her Windsor Castle residence. Her Majesty referenced her encounter with Covid-19 as she took part in a virtual visit to The Royal London Hospital on Wednesday to mark the official opening of its Queen Elizabeth Unit. "It does leave one very tired and exhausted, doesn't it? This horrible pandemic. It's not a nice result," she said in video footage released by Buckingham Palace on Sunday. The Queen made the comments as she spoke to former Covid-19 patient Asef Hussain and his wife Shamina. Asef became severely ill after contracting the virus and his brother and father died from Covid-19 while he was on a ventilator at the hospital. He is still recovering. She also spoke with NHS staff about caring for patients amid the pandemic and said, "It's been very nice to join you, and also to hear about what happened, and how well it has been achieved. Thank you very much indeed, all of you." Although the monarch appeared at the Service of Thanksgiving for her late husband Prince Philip last month, her public outings have become increasingly rare. On Friday, palace officials announced that she would miss the Royal Maundy Service, a pre-Easter tradition, at Windsor Castle on Thursday. Her son Prince Charles and his wife Camilla, Duchess of Cornwall will attend in her place.