The world's longest reigning monarch was filmed getting out of a royal car at around 10:55 am (1055 GMT) for the service, accompanied by 95-year-old husband Prince Philip, who was also hit by the bug.
Despite her illness, the queen continued to receive her red boxes containing official papers, and spent Christmas at Sandringham with members of her family, as normal.
However, the royal couple's journey from London to the estate was delayed by a day because of their illnesses.
When she failed to appear on Christmas Day, speculation grew about the queen's health, and a fake report on Twitter that she died prompted news stories in some of the tabloid newspapers.
Copyright Agence France-Presse, 2017