Hantavirus can cause serious viral infections that may affect the lungs and kidneys. Some types may lead to hantavirus pulmonary syndrome, a severe condition involving fluid accumulation in the lungs, shortness of breath, and respiratory failure. Other types may impair kidney function and cause fever, blood pressure changes, reduced urination, and kidney failure. Transmission usually occurs when people inhale dust contaminated with the urine, feces, or saliva of infected rodents. For this reason, poorly ventilated indoor areas with possible rodent exposure should be handled with caution.