Soil, water and food are all nonliving reservoirs of infection.

Soil can harbor potential pathogens of many kinds, ranging from Bacillus anthracis to E. coli O157:H7, Mycobacterium leprae to Pseudomonas aeruginosa.

Water can serve as a reservoir and vehicle for Vibrio cholera, E. coli, Cryptosporidium parvum, Entamoeba hystolytica, Giardia lamblia and many other pathogens.  The first outbreak of Legionnaires' Disease in the 1970s was the result of a plugged air conditioner condenser drain that allowed Legionella pneumophila to reproduce and be spread as aerosol droplets in the recirculated air of a Philadelphia hotel.

Meat, milk and vegetables can all harbor pathogens and serve as vehicles for transmission of infectious disease either directly or when contaminated owing to unsanitary food handling techniques.