Update: outbreak of hantavirus infection--southwestern United States, 1993.

Since May 1993, the New Mexico Department of Health, the Arizona Department of Health Services, the Colorado Department of Health, the Utah Department of Health, the Indian Health Service (IHS), and CDC, with the assistance of the Navajo Nation Division of Health, have been investigating an outbreak of acute illness characterized by a prodrome most commonly including fever, myalgias, headache, and cough, followed rapidly by respiratory failure. Preliminary laboratory findings have suggested this outbreak is associated with infection with a hantavirus or a closely related agent. This report updates the ongoing investigation of this outbreak.