Abstract: On June 27, 2004, Employee #1, a wildlife research technician working and living at Meadow Valley UC Forestry Camp in the Plumas National Forest, was hospitalized at Washoe Medical Center in Reno, Nevada with Hantavirus Pulmonary Syndrome from June 26 through July 1, 2004. The Nevada State Public Health Laboratory confirmed Hantavirus on July 2, 2004. The employer, UC Davis Wild Life Biology Department, had a research crew of 8 to 12 field employees (including Employee #1) conducting a study on small wild mammals such as deer mice (Peromyscus sp.) and other native rodents. This research crew, live-trapped, handled and tagged un-anesthetized deer mice (Peromyscus sp.). These duties involved exposure to infectious urine, feces, and saliva of deer mice. The employees did not use hand, eye or respiratory protection while performing these activities. Animal trapping equipment and related supplies were being reused without disinfection. Employee #1 and other coworkers received rodent bites on their bare hands. The deer mouse is the host for Sin Nombre Virus (SNV), the primary causative agent of Hantavirus Pulmonary Syndrome (HPS) in the United States. This viral agent causes HPS through exposure from rodent excreta and saliva via aerosol transmission or through infected saliva transmitted during bites.