After mosquitoes from Yoyogi Park tested positive for dengue fever, Tokyo government officials decided to close major portions of the park that has been linked to the first indigenous dengue fever cases in some 70 years.

Aedes mosquito
Aedes aegypti image/CDC

Mosquitoes caught in four of the 10 traps set up in the park on Sept. 2 were found to be carrying the virus that causes dengue fever, according to a Asahi Shimbun report today. “After detecting dengue virus from a wide area of Yoyogi Park, the Tokyo government in order to ensure public safety is to close the area from 2:00pm today for the time being,” the metropolitan government said in a statement.

The dengue case count has now climbed to 55 cases, health ministry officials confirm. The patients are from 11 different prefectures around Japan, all with no recent international travel.

Earlier this week, two models, Saaya, 20, and Eri Aoki, 25, who were filming for “King’s Brunch,” a variety show, in the park, contracted the virus, the Nikkan Sports newspaper reported. There has been no fatalities linked to this outbreak.

A teenage girl from Saitama Prefecture, which was reported  last Wednesday, was the first locally acquired dengue case in Japan since 1945.

Dengue is transmitted by the bite of a mosquito infected with one of the four dengue virus serotypes. It is a febrile illness that affects infants, young children and adults with symptoms appearing 3-14 days after the infective bite.

Dengue is not transmitted directly from person-to-person and symptoms range from mild fever, to incapacitating high fever, with severe headache, pain behind the eyes, muscle and joint pain, and rash. There is no vaccine or any specific medicine to treat dengue. People who have dengue fever should rest, drink plenty of fluids and reduce the fever using paracetamol or see a doctor. For more infectious disease news and information, visit and “like” the Infectious Disease News Facebook page