Harvest mites (genus Trombicula; also known as red bugs, trombiculid mites, scrub-itch mites, berry bugs or, in their larval stage, as chiggers) are mites in the family Trombiculidae that live in forests and grasslands. In their larval stage they attach to various animals including humans and feed on skin, often causing itching. These relatives of spiders are nearly microscopic measuring 0.4 mm (1/100 of an inch) and have a chrome-orange hue. A common species of Harvest mite in Northern America is Trombicula alfreddugesi; in the UK the most prevalent Harvest mite is Trombicula autumnalis. The conservation status of a species is an indicator of the likelihood of that species continuing to survive either in the present day or the future. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... For other uses, see Animal (disambiguation). ... Subphyla and Classes Subphylum Trilobitomorpha Trilobita - trilobites (extinct) Subphylum Chelicerata Arachnida - spiders,scorpions, etc. ... Orders Acarina Amblypygi Araneae Opiliones Palpigradi Pseudoscorpionida Ricinulei Schizomida Scorpiones Solifugae Uropygi The arachnids, Arachnida, are a class of invertebrate animals in the subphylum Chelicerata. ... Families Tetranychidae - Spider mites Eriophyidae - Gall mites Sarcoptidae - Sarcoptic Mange mites The mites and ticks, order Acarina or Acari, belong to the Arachnida and are among the most diverse and successful of all the invertebrate groups, although some way behind the insects. ... A larval insect A larva (Latin; plural larvae) is a juvenile form of animal with indirect development, undergoing metamorphosis (for example, insects or amphibians). ... Look up mite in Wiktionary, the free dictionary. ... Diversity 111 families, 40,000 species Suborders Mesothelae Mygalomorphae Araneomorphae  See table of families Wikispecies has information related to: Spiders Spiders are predatory invertebrate animals that have two body segments, eight legs, no chewing mouth parts and no wings. ... A millimetre (American spelling: millimeter, symbol mm) is an SI unit of length that is equal to one thousandth of a metre. ...

Life cycle

Harvest mite larvae are small, tiny, irritating, red immatures between the egg and nymph stages, which have not yet become adult mites. They are usually microscopic. The larvae often live in berry patches, tall grass and weeds, woodland edges, pine straw, leaves, and treebark, or in typical habitats of their hosts (especially rodents). A larval insect A larva (Latin; plural larvae) is a juvenile form of animal with indirect development, undergoing metamorphosis (for example, insects or amphibians). ... Praying mantis nymphs, approximately 4mm long, clustered on a leaf In biology, a nymph is the immature form of some insect species, which undergoes incomplete metamorphosis (Hemimetabolism) before reaching its adult stage; unlike a larva, a nymphs overall form already resembles that of an adult. ... A microscope (Greek: micron = small and scopos = aim) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ... Subfamilies There are 7 subfamilies: Subfamily Arundinoideae Subfamily Bambusoideae Subfamily Centothecoideae Subfamily Chloridoideae Subfamily Panicoideae Subfamily Pooideae Subfamily Stipoideae The true grasses are monocotyledonous plants (Class Liliopsida) in the Family Poaceae, also known as Gramineae. ... Yellow starthistle, a thistle native to southern Europe and the Middle East that is an invasive weed in parts of North America. ... Leaves are an Icelandic five-piece alternative rock band who came to prominence in 2002 with their debut album, Breathe, drawing comparisons to groups such as Coldplay and Doves. ... For other meanings of bark, see Bark (disambiguation). ...

Larva mite found in North America Image File history File links No higher resolution available. ...

The larval mites feed on the skin cells, but not blood, of animals, including humans. The six-legged parasitic larva feeds on a large variety of creatures including humans, rabbits, toads, box turtles, quail, and even some insects. After crawling onto their host, they inject digestive enzymes into the skin that break down skin cells. They do not actually "bite," but instead form a hole in the skin and chew up tiny parts of the inner skin, thus causing severe irritation and swelling. The severe itching is accompanied by red pimple-like bumps (papules) or hives and skin rash or lesion on a sun-exposed area. For humans, itching usually occurs after the larvae detach from the skin. Chiggers are known for never spreading from host to host. Beyond overall skin structure, refer below to: See-also. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell being used to describe the smallest unit of a living organism Cells in culture, stained for keratin (red) and DNA (green) The cell is the... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... For other uses, see Animal (disambiguation). ... This article is about modern humans. ... A larval insect A larva (Latin; plural larvae) is a juvenile form of animal with indirect development, undergoing metamorphosis (for example, insects or amphibians). ... This article is about modern humans. ... Genera Pentalagus Bunolagus Nesolagus Romerolagus Brachylagus Sylvilagus Oryctolagus Poelagus Rabbits are small mammals in the family Leporidae of the order Lagomorpha, found in several parts of the world. ... Families At least 9, see article. ... Genera Cuora Pyxidea Terrapene The box turtle is one of several species of turtles. ... Genera Coturnix Anurophasis Perdicula Ophrysia † See also Pheasant, Partridge, Grouse Quail is a collective name for several genera of mid-sized birds in the pheasant family Phasianidae, or in the family Odontophoridae. ... Orders Subclass Apterygota Archaeognatha (bristletails) Thysanura (silverfish) Subclass Pterygota Infraclass Paleoptera (Probably paraphyletic) Ephemeroptera (mayflies) Odonata (dragonflies and damselflies) Infraclass Neoptera Superorder Exopterygota Grylloblattodea (ice-crawlers) Mantophasmatodea (gladiators) Plecoptera (stoneflies) Embioptera (webspinners) Zoraptera (angel insects) Dermaptera (earwigs) Orthoptera (grasshoppers, etc) Phasmatodea (stick insects) Blattodea (cockroaches) Isoptera (termites) Mantodea (mantids) Psocoptera... Look up Pimple in Wiktionary, the free dictionary. ... A papule is a small, solid and usually conical elevation of the skin. ... Urticaria or Hives is a relatively common form of allergic reaction that causes. ... For the manga by Tsukasa Hôjô, see Rash. ...

After feeding on their hosts, the larvae drop to the ground and become nymphs, then mature into adults which have 8 legs and are harmless to humans. In the post larval stage, they are not parasitic and feed on plant materials. The females lay 3-8 eggs in a litter, usually on a leaf or under the roots of a plant, and die by autumn. This article or section does not cite any references or sources. ...

Where harvest mite are found

Many areas of the world are plagued by chiggers, or some form thereof. In Europe and North America, they tend to be more prevalent in the hot and humid parts. In the more temperate regions, they are found only in the summer (in French, harvest mice are called aoûtat, or "August" flies). In the United States, they are found mostly in the south east, the south, and the midwest. They are not present, or barely found, in far northern areas, in high mountains and in deserts.

Chiggers as disease vectors

Although the harvest mite chigger usually does not carry diseases in North American temperate climates, the mites are considered a dangerous pest in East Asia and the South Pacific because they often carry scrub typhus, which is known alternatively as the Japanese river disease, scrub disease, or tsutsugamushi. The mites usually are infected by the disease by their infected rodent hosts. The disease is transmitted to the next generation of offspring by breeding mites. Symptoms of scrub typhus in humans include fever, headache, muscle pain, cough, and gastrointestinal symptoms. In geography, temperate latitudes of the globe lie between the tropics and the polar circles. ... East Asia Geographic East Asia. ... For other uses, see Oceania (disambiguation). ... Scrub typhus is a form of typhus caused by Orientia tsutsugamushi and transmitted by chiggers, which are found in areas of heavy scrub vegetation. ... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and...

The North American genus and species can cause severe illness in children. This only occurs when the infestation is particularly heavy. Symptoms include a hallucinatory sense of floating outside one's body, fatigue, fever and general malaise.

Myth versus fact

Contrary to popular belief, the larvae do not burrow deep into the skin and live there. Rather, the larvae pierce the skin and inject powerful enzymes that digest cellular contents, which become liquified and are consumed by the larvae.^[1]

Another myth is that application of rubbing alcohol kills the chiggers or helps with symptoms. This method serves only to cause great burning pain and discomfort to the victim.

Treatment

The most effective way of removing chiggers is by taking a hot shower and washing the affected areas with mildly hot water and soap. This must be done as soon as possible after exposure or possible exposure. Carefully wash the ankles, feet, behind the knees, and under the arms and chest. An Epsom salt bath may help alleviate pruritus). Another good way of removing chiggers is yo cover the chiggers with scotch tape and pull them off that way. However once symptoms appear, it may be too late to prevent further bites. Taking a hot bath when already covered with chigger bites may in fact be very uncomfortable and increase itching symptoms. Do not rub and scratch the skin aggressively, but instead gently but firmly rub the irritated skin with warm soapy water. This article is about the computer protocol. ... Magnesium sulfate (commonly called Epsom salts in hydrated form) is a chemical compound with the formula MgSO4·7H2O. Origin Epsom salt was originally prepared by boiling down mineral waters at Epsom, England and afterwards prepared from sea water. ... An itch (Latin: pruritus) is a sensation felt on an area of skin that makes a person or animal want to scratch it. ...

Clothing, especially pants and socks, should be immediately discarded after returning from areas where exposure may have occurred.

Try not to scratch the affected regions. Scratching could scrape off chigger larvae, but it may also cause increased irritation by breaking the skin and leaving it vulnerable to a more serious infection. An infection is the detrimental colonization of a host organism by a foreign species. ...

A covering to reduce air exposure over the itchy area, such as calamine lotion, petroleum jelly, or baby oil, may help relieve the pain (but does not cure the bites). Calamine lotion is a zinc-based antipruritic typically used to treat sunburn, eczema, rashes and insect bites and stings. ... Petroleum jelly, vaseline, petrolatum or soft paraffin [3] is a semi-solid mixture of hydrocarbons, originally promoted as a topical ointment for its healing properties. ... Mineral oil or liquid petrolatum is a by-product in the distillation of petroleum to produce gasoline. ...

The application of a small drop of finger nail polish (usually clear nail polish) is one of the most popular remedies and is claimed to reduce itching and dry the itchy sores in the fewest number of days. This has abetter chance of being effective if done early. Later, people sometimes may end up mistaking the red dot in the middle of the bite as the chigger itself (the chigger is long gone). There is a misconception that the mite has burrowed into the skin, and varnish will "suffocate" the chigger by coating their bites with vaseline or nail polish, or some other air-inhibiting seal.

Rubbing alcohol is not recommended and it is very painful, and no more effective than other measures.

Medication such as antihistamines or corticosteroid creams may be prescribed by doctors, and might help in some instances. An antihistamine is a drug which serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions, through action at the histamine receptor. ... In physiology, corticosteroids are a class of steroid hormones that are produced in the adrenal cortex. ...

Prevention

Chiggers seem to affect warm covered areas of the body more than drier areas. Thus, areas covered by socks and shoes, behind the knees and around the groin are often trouble spots. Special attention should be given to small children, as areas higher in the body (chest, back, waist-band, and under-arms) may be affected more easily than in adults, since children are shorter and may more likely than adults come in contact with low-lying vegetation and dry grass where chiggers thrive.

To avoid being afflicted by chiggers, always wear tight weave, protective clothing and long pants. Spray insect repellent on your skin for further protection. Application of repellent to the shoes and lower trousers is helpful. Staying on trails, roads, or paths can help prevent contact.

Dusting sulfur is used commercially for mite control and can be used to control chiggers in yards. The dusting of shoes, socks and trouser legs with sulfur can be highly effective in repelling chiggers.

People who pick wild blueberries in the summer have traditionally been very vulnerable to chigger bites and have suggested applying deodorant soap to the skin and letting it dry without rinsing may help prevent bites.

Another helpful avoidance is to recognize the chigger habitat to avoid exposure in the first place. Chiggers in North America thrive late in summer, in dry tall grasses and other thick, unshaded vegetation.

Insect repellents containing one of the following active ingredients are recommended: DEET, Catnip oil extract - Nepetalactone, Citronella or eucalyptus oil extract. However, a study reported in the March 1993 issue of the Southeast Asian Journal of Tropical Medicine & Public Health (volume 24, issue 1: pp165-169) tested two commercial repellants: DEET and citrus oil: "All chiggers exposed on the filter papers treated with DEET died and did not move off the treated papers. None of the chiggers that were placed on papers treated with citrus oil were killed." It was concluded that DEET was more effective than citrus oil. Meta-N,N-diethyl toluamide, abbreviated DEET, is an insect-repellent chemical. ... It has been suggested that this article or section be merged with Nepeta. ... Structural formula of nepetalactone Nepetalactone is a lactone chemical compound first isolated in the plant catnip, Nepeta cataria (apparently named after the Italian town of Nepete). ... Species Over 50: see text Lemon Grass Lemon grass or lemongrass is a perennial herb used in Asian (particularly Thai, Khmer and Vietnamese) and Caribbean cooking. ... natural range Species About 700; see the List of Eucalyptus species Eucalyptus (From Greek, ευκάλυπτος = Well covered) is a diverse genus of trees (and a few shrubs), the members of which dominate the tree flora of Australia. ...

Chiggers can also be treated using common household vinegar (5% acetic acid). This was reported in the March 12, 2001 issue of the Archives of Internal Medicine.

See also

• Mite
• Chigoe flea

Look up mite in Wiktionary, the free dictionary. ... The chigoe flea (Tunga penetrans; also known as Sarcopsylla penetrans or Pulex penetrans) is a parasitic arthropod found in tropical climates, especially South America and the West Indies. ...

References

• The World Book Encyclopedia, 2000 ed.
• Encyclopædia Britannica, 2005 ed. Accessed with paid subscription.
• Tideland Treasure: The Naturalist's Guide to the Beaches and Salt Marshes of Hilton Head Island and the Southeastern Coast, Revised Edition, by Todd Ballantine.

1. ^ Finke, D.L. (1998-10-01). University of MD Chigger Factsheet. Retrieved on 2007-05/25.

"Give Chiggers The Brush," Mother Earth News; June/July 2005, Issue 210, p 93-98 World Book Encyclopedia is, according to its publisher in the United States, the number-one selling print encyclopedia in the world. ... The Encyclopædia Britannica is a general English-language encyclopaedia published by Encyclopædia Britannica, Inc. ... Year 1998 (MCMXCVIII) was a common year starting on Thursday (link will display full 1998 Gregorian calendar). ... is the 274th day of the year (275th in leap years) in the Gregorian calendar. ...

External links

• http://www.hgic.umd.edu/_media/documents/hg79_000.pdf
• "Chiggers!" at Missouri Department of Conservation
• Chiggers at Pestproducts.com
• Iowa State University Department of Entomology Insect Information Note
• NIH Medline Plus
• Ohio State University Extension Fact Sheet, Entomology, Chiggers, HYG-2100-98
• Trombicula autmunalis