The Centers for Disease Control and Prevention provide a general introduction to getting rid of fleas for pet owners.40 For specific guidance on flea-eradication strategies and specific flea-control products, advise patients to seek the advice of their veterinarian.
Flies and biting midges
Flies are 2-winged insects belonging to the order Diptera. Several fly species can bite, causing a local inflammatory reaction; these include black flies, deer flies, horse flies, and sand flies. Signs and symptoms of a fly bite include pain, pruritus, erythema, and mild swelling (FIGURE 5).41,42 Flies can transmit several infections, including bartonellosis, enteric bacterial disease (eg, caused by Campylobacter spp), leishmaniasis, loiasis, onchocerciasis, and trypanosomiasis.43
Biting midges, also called “no-see-ums,” biting gnats, moose flies, and “punkies,”44 are tiny (1-3 mm long) blood-sucking flies.45 Bitten patients often report not having seen the midge because it is so small. The bite typically starts as a small, erythematous papule that develops into a dome-shaped blister and can be extraordinarily pruritic and painful.44 The majority of people who have been bitten develop a hypersensitivity reaction, which usually resolves in a few weeks.
Management.Suppressing adult biting midges with an environmental insecticide is typically insufficient because the insecticide must be sprayed daily to eradicate active midges and generally does not affect larval habitat. Insect repellents and biopesticides, such as oil of lemon eucalyptus, can be effective in reducing the risk of bites.44,45
Mosquitoes
Mosquitoes are flying, blood-sucking insects of the order Diptera and family Culicidae. Anopheles, Culex, and Aedes genera are responsible for most bites of humans.
Most spiders found in the United States can’t bite through human skin. Common exceptions are black widow and brown recluse spiders.
The bite of a mosquito produces an indurated, limited local reaction characterized by a pruritic wheal (3-29 mm in diameter) with surrounding erythema (FIGURE 6) that peaks in approximately 30 minutes, although patients might have a delayed reaction hours later.46 Immunocompromised patients might experience a more significant local inflammatory reaction that is accompanied by low-grade fever, hives, or swollen lymph nodes.46,47
Mosquitoes are a vector for serious infections, including dengue, Japanese encephalitis, malaria, and yellow fever, and disease caused by Chikungunya, West Nile, and Zika viruses.
