CHAPTER XXXVII
TSUTSUGAMUSHI
Definition and Synonyms
Definition.—This is an acute febrile disease caused by the bite of the larval Kedani mite of the region where the infection prevails. The onset is characterized by headache and giddiness, a rather rapidly rising temperature and swelling of the lymphatic glands draining the region in which is situated a small necrotic ulcer marking the site of the bite. With injected conjunctivae, continuous fever and hyperaesthesia, the disease goes on for about a week when a macular eruption appears about face, then chest, extremities and trunk. About ten days after the appearance of the eruption there is a fall of fever by lysis.
Fig. 139.—The Kedani mite. Trombidium akamushi. (From Ruge and zur Verth.)
Synonyms.—Flood fever, Japanese River fever, Kedani mite disease. Shimamushi.
History and Geographical Distribution
History.—There are records which would indicate that the disease has been known for more than 1000 years.
Geographical Distribution.—It is only in the western part of the island of Nippon, when the banks of the Shinanogawa are inundated each spring, that we find the disease. The disease is supposed to be confined to Japan although Ashburn and Craig have thought a disease observed by them in the Philippines as possibly identical.