Princess Aiko tested positive for type A influenza on December 23.

According to the Imperial Household Agency,  the princess had a fever topping 38 degrees celsius on December 22 and coughs. 

Her fever went down below 38 degrees on the morning of December 23, but she was diagnosed with the flu. 

Princess Aiko’s plan to visit her grandfather Emperor Emeritus Akihito, who turned 91 years old on December 23, was cancelled. She has cancelled official duty plans and will take time off her work, and will be resting at her residence until December 27.

Emperor Naruhito and Empress Masako did not show any symptoms, but cancelled plans to celebrate Emperor Emeritus Akihito’s birthday.