Relatively few of the parasites transmitted terrestrially seek their next host actively. Parasites must be mobile to seek out hosts, and significant mobility on land is restricted to the parasitic arthropods. Nematodes have limited mobility and use it primarily to place themselves in habitats where they are likely to come in contact with hosts.
Larvae of the hookworm nematodes will climb and accumulate on the surface of the ground. They wait to ambush a passing host and will actively penetrate the skin.
Some parasitic flies such as Lipoptena possess wings early in life and can fly in search of hosts. the wings are lost after a host is found.
Fleas possess well-developed legs to jump onto passing hosts.
Lice and mites can crawl from one host to another if those hosts come in contact.
