A vector-borne disease is one in which the pathogenic microorganism is transmitted from an infected individual to another individual by an arthropod or other agent. The most common vectors are mosquitoes, ticks, and bed bugs.
A zoonotic disease is a disease which can be transmitted from animals to humans. The disease may or may not produce clinical illness in the animal. The purpose of the zoonotic disease program is focused on preventing transmission of diseases from animals to humans. Although there are many zoonotic diseases, local health districts typically deal with rabies through animal bites reported by clinics, hospitals or the dog warden.