Princess Yoko of Japan has been hospitalised with pneumonia after testing positive for COVID-19.
The 38-year-old, who is the second daughter of the late Prince Tomohito of Mikasa, was first admitted to a hospital inside the Imperial Palace last week but has since been transferred to the University of Tokyo Hospital, Town & Country reports.
The princess tested positive on 8 February after complaining of a sore throat the previous day. It is not known whether she has received her COVID-19 vaccinations.
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Her sister, 40-year-old Princess Akiko, tested negative for coronavirus despite the pair having been in close contact before her diagnosis.
Their father, who died of cancer aged 66 in 2012, was a first cousin of former Emperor Akihito.
Princess Yoko was born on 25 October 1983 at the Japanese Red Cross Medical Center in Hiroo, Shibuya, Toyko. She was educated at the prestigious Gakushūin School and is a graduate of the Gakushuin Women's College.
In the past she has volunteered with the Japanese Red Cross and was also inaugurated as the President of the Social Welfare Organization Yuai Jyuji Kai in January 2014.
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Charles and Camilla are currently both self-isolating
Princess Yoko is one of many royals to have tested positive for coronavirus in the past week.
Clarence House confirmed last week that the Prince of Wales has contracted the virus for a second time, and on Monday, the Duchess of Cornwall also produced a positive result.
Last week, Queen Magrethe of Denmark and King Felipe of Spain were also isolating after testing positive for COVID-19.
On Monday, the Danish court confirmed that a doctor has assessed that the queen can end her isolation after having a mild case of the virus.
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