Mouse feces indicate areas where mice are most active. Measuring approximately 3 to 6 mm in length, they are granular in shape and black in color. Mouse feces are commonly mistaken for cockroach or rat droppings.
Mouse droppings are concentrated near breeding and nesting grounds, although they may also be seen in other areas of the house from time to time. Feces are also present near items that have been destroyed by mice during the nesting process. They can be found in chewed cardboard boxes, invaded drawers and near damaged electrical wiring.
These droppings may carry harmful bacteria, diseases and viruses and should not be handled without the use of protective gloves and an OSHA-approved respirator and functioning cartridges. Hantavirus is contracted through the inhalation of particles of contaminated feces, as well as inhalation or ingestion of an infected mouse's saliva or urine. Disturbed droppings are more likely to emit virus particles, so it is unwise to sweep or vacuum areas where feces have been found. Rather, droppings should be picked up carefully and disposed of in plastic bags.