Evidence is presented that the chikungunya virus is in South Vietnam and is capable of producing a distinct clinical syndrome in Americans. The illness is short-lived and is manifested by an acute onset of fever, chills, headache, arthralgia, and signs of arthritis with or without macular rash. The illness is generally mild and does not appear to be life-threatening. Although the number of cases reported in this series is small, the number of American troops that may come in contact with this virus is large, and the potentiality of this problem is at present unknown.
Formerly Chief of Medicine, 93rd Evacuation Hospital, Long Binh, Vietnam; currently Chief of General Medical Service, Letterman General Hospital, San Francisco, California.
Chief, Department of Virology, USA Component, SEATO Medical Research Laboratory, Bangkok, Thailand.