deer mouse

The virus can spread through the urine, feces or saliva of wild rodents, including deer mice, which are common in many parts of California, according to the California Department of Public Health.

In North America, deer mice are the most common carriers, according to the Mayo Clinic.

The deer mouse is the most common vector of hantavirus pulmonary syndrome in the U.S., according to the CDC.

Whereas the deer mouse is promiscuous -- even a single litter of pups can have four different fathers -- the oldfield mouse mates for life.

Even though they are smaller, they prey upon native ground squirrels and deer mice with formidable teeth and claws that are larger than those on the mainland.