rodents. they say hanta virus has a six week incubation period. mortality rate of about 38% which means more than a third of the people with the disease will die. >> because of shortness of breath and coughs that goes to respiratory failure. we have to put patients on mechanical ventilation. >> reporter: park officials closed the luxury cabins saying the double wall design made it easy for mice to nest between the walls. a report from the state department warned park officials that rodent inspection efforts after a visitor fell ill. state says while officials in yosemite did take steps to deal with the row dented problem, there are limitations given the location. campers are worried. >> i just think about it. i know my dad was calling me. he was concerned about it. >> it seems like a low risk, if