With large eyes and ears, deer mice measure 2-3 inches, or 5-7.5 cm, in length with another 2-3 inches added for their tails. Ranging from gray to reddish brown, they display white undersides with bi-colored tails.
Deceptively cute and cuddly, deer mice can carry the Hantavirus strain, Sin Nombre, or SNV, a cardio-pulmonary respiratory disease that manifests in flu-like symptoms such as fever, coughs, body aches, headaches and an acute lack of energy. Characterized by a sudden onset of shortness of breath with rapidly evolving pulmonary edema, Hantavirus can prove fatal, despite mechanical ventilation and intervention with potent diuretics.
Deer mice are also primary carriers of Lyme disease, caused by the bacterium Borrelia burgdorferi, transmitted to humans through the bite of infected ticks. Symptoms include fever, headache, fatigue and a skin rash. If left untreated, Lyme disease can spread to joints, the heart and the central nervous system.