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Arthropod Bites and Stings

»	What are arthropods? Are most arthropods harmful to humans?
»	Describe various ways arthropods injure humans. What insect or arachnid would cause the injury?
Bites and Stings
»	How do you diagnose a bite or sting?
»	Why are some bites and stings extremely painful or dangerous while others are simply itchy, red, irritating papules?
»	One person on a hike is “eaten alive” by mosquitos while his companions are not bothered at all. Do ectoparasites such as mosquitos, ticks, fleas, and mites bite randomly?
»	Why are bite reactions to ectoparasites so much different in different people?
»	How do you treat bee stings?
»	What are the signs of serious systemic reactions to bee, wasp, or ant stings?
»	How do you treat anaphylactic syndrome from a bee sting?
»	What are the unique characteristics of fire ants and their sting?
»	What species of spiders are medically important?
»	How do you diagnose and treat the black widow spider bite?
»	How do brown recluse spider bites present?
»	How should brown recluse spider bites be treated?
Infestations
»	What is scabies?
»	How is scabies characterized clinically?
»	What is Norwegian scabies?
»	What agents are used to treat scabies?
»	Discuss the three varieties of lice that affect humans.
»	How should lice infestations be treated?
Zoonotic Infestations
»	How do flea infestations typically present?
»	How do you treat a flea infestation?
»	How is Cheyletiella infestation recognized in humans? In animals? How does it compare to canine scabies?
»	Where do bedbugs live? What do their bites look like?
»	Do species of bedbugs that parasitize other animals bite humans?
»	What are zoonotic dermatoses?
Insect Vectors
»	What are the kissing, or assassin, bugs?
»	Why are kissing bugs important?
»	What diseases are transmitted by ticks?
»	What is the most common tick-borne infectious disease in the United States?
»	How does Lyme disease present?
»	Why do the tick bites often go unnoticed?
»	How do tick bites affect humans? How are ticks removed once they are attached to the skin?
»	How do you prevent tick bites?
»	Name some important arthropod-borne diseases.
»	What are the most effective insect repellents?

What are the most effective insect repellents?

The most effective repellent for the prevention of bites of mosquitos, chiggers, blackflies, midges, and fleas is DEET. An 8% to 10% concentration is adequate for children and a 20% to 50% concentration for adults. A new preparation, extended-duration topical arthropod repellent (Editar), provides a slow release and is marketed by 3M as Ultrathon and by Amway as Hour Guard. Permethrin aerosol (Permanone) applied to clothing is the best tick repellent.

Elston DM: Insect repellents: an overview, J Am Acad Dermatol 38:644–645, 1998.