Fortunately, humans encounter only a few of these species. The homeowner may also occasionally encounter the dog flea, the human flea and the oriental rat flea. The few others found in the state are encountered even less often. Fleas are medically important because of their irritating bites, abundance, worldwide distribution and ability to transmit diseases. Flea bites Different people have differing reactions to flea bites.
Some people are either immune to the bites, unattractive to fleas, or both.
Others seem to be highly attractive to fleas. In a flea-infested household, one or two individuals may show severe irritation from the bites, while others may not even realize fleas are present. Fleas prefer the blood of pets. Thus, people may coexist with the pet and the pet's flea population while being bitten only occasionally. When the pet is removed from the environment, such as during a family vacation, a large population of hungry adult fleas may accumulate.