When he initially opened the door of the truck he noted the strong odor of rodent excreta. Later investigation of the truck revealed evidence of rodent infestation. All members of the genus have specific rodent hosts that serve as reservoirs for the virus. Although this is the only reported case of HPS in Oklahoma, others can be expected to follow. The virus is present in the urine, feces and saliva of infected rodents, which are persistently infected and asymptomatic.
Human infection occurs primarily via inhalation of aerosolized infected rodent excreta.
The highest risk of infection appears to be exposure to an enclosed, unventilated structure in which infected rodents have been present, such as the truck cab in this case. HPS presents initially as a nonspecific febrile illness and progresses rapidly to respiratory insufficiency from noncardiac pulmonary edema. The most common physical findings include tachycardia, tachypnea and hypotension. Common laboratory findings include a left-shift neutrophilic leukocytosis, hemoconcentration and thrombocytopenia. Although the above findings may suggest the diagnosis of HPS, viral-specific diagnostic tests are necessary to confirm the diagnosis.