Toronto: Canadian Prime Minister Justin Trudeau's wife has tested positive for the new coronavirus, a week after appearing on a panel in London with former Australian prime minister Julia Gillard.

Sophie Gregoire Trudeau became mildly ill this week, and doctors tested her for the virus after she developed a low fever that has since passed. She and her husband voluntarily isolated themselves on Thursday.

Last week, Gregoire Trudeau attended a charity event in Britain and was part of a panel with Gillard and singer Leona Lewis. She also posed for a photograph in a small group that included Lewis Hamilton, the Formula One driver, and actor Idris Elba.

Sophie Gregoire Trudeau, left, was on a panel with Julia Gillard and Leona Lewis in London last week. Credit:Getty Images

The event, held on March 4, was organised by the development charity We, an organisation for which Trudeau serves as an ambassador. She was introduced on stage by Lewis, who greeted her with a hug. Video of the event also shows her kissing Gillard.