Mite bites

[Tariq Zaki]

Mites, like ticks, are closely related to spiders. Biting mites, sometimes carried as parasites on the bodies of humans and animals, may transmit disease to humans.
(See also Introduction to Bites and Stings and Tick Bites.)
Mite infestations are common and are responsible for the intensely itchy rash caused by the bites of chiggers (mite larvae), for scabies, other itchy rashes, and a number of other disorders. The effects on the tissues around the bite vary in severity. In some Asian countries and Australia, chiggers may transmit scrub typhus.
Mites that bite come from a variety of sources, including

Birds
Rodents
Cats, dogs (especially puppies), and rabbits
Pigs
Straw, hay, seeds, and other plant material

Some mites, such as those that cause scabies, bite and burrow under the skin. Demodex mites cause a similar rash (sometimes called mange).
Some mites do not bite, but they cause allergic reactions such as

Grocer

[Cami]

There are multiple kinds of biting mites. Chiggers are probably the most common. Chiggers are mite larvae that are ubiquitous outdoors except in arid regions; they bite, feed in the skin, then fall off. Outside the US, chiggers may carry Orientia tsutsugamushi (see Scrub Typhus). They do not burrow into the skin, but because they are small, they are not readily seen on the skin surface.
Common mite species that bite and burrow into the skin include Sarcoptes scabiei, which causes scabies, and Demodex mites, which cause a scabies-like dermatitis (sometimes referred to as mange).
Dermatitis is caused by mites that occasionally bite humans but are ordinarily ectoparasites of birds, rodents, or pets and by mites associated with plant materials or stored food or feed.

Bird mites may bite people who handle live poultry or pet birds or who have birds’ nests on their homes.
Rodent mites from cats, dogs (especially puppies), and rabbits may bite people.
Swine mange mites (S. scabiei var suis) from pig farms or pet pigs may also bite humans.
The straw itch mite (Pyemotes tritici) is often associated with seeds, straw, hay, and other plant material; it is a parasite of soft-bodied insects that are or have been present in such materials. These mites often bite people who handle the infested items. Granary workers, people who handle grass seeds or grass hay, and people who make dried plant arrangements are most at risk.

Allergic dermatitis, or grocer’s itch, is caused by several species of mites associated with stored grain products, cheese, and other foods. These mites do not bite but cause allergic dermatitis because people become sensitized to allergens on the mites or their waste products.
House dust mites do not bite but feed on sloughed skin cells in pillows and mattresses and on floors (especially on carpets). They are significant because many people develop pulmonary hypersensitivity to allergens in the exoskeletons and feces of house dust mites.