Prince Hisahito, the only son of Crown Prince Fumihito and second in line to the throne, has tested positive for the novel coronavirus, the Imperial Household Agency announced on Sept. 14. 

The 17-year-old is currently experiencing a high fever.

This is the eighth case of a member of the imperial family contracting COVID-19.

Hisahito is a second-year student at the University of Tsukuba’s Senior High School in Tokyo's Bunkyo Ward. According to the agency, the prince had no fever and attended school on the morning of Sept. 13.

However, he developed a fever shortly after returning home from school that day.

Both the antigen tests for COVID-19 and influenza initially came back negative. However, as his fever persisted on the morning of Sept. 14, another antigen test was conducted, revealing a positive result for COVID-19.

Hisahito will receive medical care at his home until Sept. 18.

A news conference by Fumihito and Crown Princess Kiko, which was scheduled for the morning of Sept. 14 ahead of their visit to Vietnam, was postponed to 11 a.m. on Sept. 15. 

The crown prince and crown princess underwent PCR tests that same day and the results came back negative for COVID-19.

(This article was written by Ryota Goto and Akiko Tada.)