Americans share their households with an estimated 140 million dogs and cats. For the truly pet-centric among us, these creatures are family members, plain and simple. And like family members, they can transmit disease to their humans, either directly through licks, bites, and scratches; indirectly by carrying other infection-laden critters like fleas and ticks into the human environment, or by shedding tiny infectious organisms into the environment through feces. As a group, these diseases are called zoonoses. Practicing good hand washing and other common-sense personal hygiene measures, and giving your pets good veterinary care, will further reduce the already low risk of getting an unwanted ailment courtesy of your “best friend.”