Flea Bites

Excerpt

Siphonaptera, more commonly known as fleas, are an order of wingless arthropods with more than 2000 species. Fleas live as ectoparasites on warm-blooded species, consuming their blood. They are small, ranging from 1.0 to 3.3 mm in size, and have long hind legs adapted for jumping. Fleas are natural jumpers (relative to body size) that can jump 100 times their length. Fleas are ubiquitous parasites that lack specificity towards their hosts. The cat flea, Ctenocephalides felis, is the most prevalent parasite on dogs. In certain regions, the human flea, Pulex irritans, is prevalent as a dog parasite. The human flea is also detected in wild animals with no human contact. Fleas of the genus Ctenocephalides have 2 ctenidia (combs) that resemble a mane of hair (pronotal comb) and a mustache (genal comb).

Though fleas survive in many environments, they are rare in low-humidity environments and elevations over 1500 ft. Fleas are predominantly a nuisance to their host, causing pruritic local reactions. They can also act as vectors for typhus, rickettsial disease, bubonic plague, protozoan, and helminth infestations. Understanding these features can help direct history-taking, the physical exam, and treatment options. Additionally, exploring eradication techniques within the human environment can help reduce the spread of disease from fleas to humans.