Humans don't usually contract HPS directly from rodents.
Rodents shed hantavirus particles in their saliva, urine and droppings.
Humans usually contract HPS by inhaling particles that are infected with the hantavirus. HPS is an airborne infectious disease. Humans then inhale these particles, which leads to the infection. Ticks, fleas, and other biting insects have not been found to trasmit HPS from rodents to humans. However, it is possible for domestic dogs and cats to bring infected rodents into contact with humans.