Grand Canyon National Park officials say two dead bats found along the Colorado River inside the park tested positive for rabies.
A statement released Thursday by park officials said the bats were deceased when collected last month and that the bats didn't come into contact with visitors or park staff.
Rabies can be fatal but is preventable if medical treatment is given after exposure to a rabid animal and before the development of symptoms.
Humans can contract rabies through contact with an infected animal's saliva, such as a bite or scratch.
All mammals are susceptible to rabies and park officials advise visitors to not approach or wildlife.