Importance
- There are over 55,000 species of mites worldwide. Many species are harmless or even beneficial as they break down organic matter. However, several species can affect the health of people and animals, including honey bees.
- Animals with mite infestations may be intensely itchy. Mites can transmit pathogens or cause hair loss, papules or nodules, thickened skin, or secondary skin infections.
- Clinical signs depend on whether the species burrows into the skin, remains on the skin surface, or inhabits hair follicles or sebaceous glands.
- Foreign vectors and foreign animal diseases (FADs) are not found in the United States and can threaten human and animal health. FADs can be introduced to the United States, so animal owners and veterinary personnel have a key role in recognizing and reporting FADs to animal and public health officials. Early signs of mite-related FADs may include:
- Unusual mite appearance
- Large number of sick or dead animals
- Unusual signs of illness (like severe skin lesions or neurological disease)
About Mites
- Mites are arachnids, relatives of spiders and ticks. They may be free-living or parasitic.
- Mites live most of their life on an animal but can live days to weeks off a host.
- Some species are restricted to one type of animal host (high host specificity). Others infect various types of hosts (low host specificity).
- Depending on the species, mites may live for several weeks to months or even decades.
- Eggs are usually laid on the host and develop into six-legged larvae.
- Larvae molt into eight-legged nymphs.
- Nymphs molt into eight-legged adults, which live on or off the animal host.
- Mites cannot jump or fly since they do not have wings.
- Mites can be transmitted from one host to another through direct contact (particularly at birth or dense animal housing) and fomites (such as fences and grooming equipment).
Identification of Mites
- Most mites are too small to be seen with the naked eye. However, many can be identified by a unique set of characteristics with the help of a dissecting microscope.
- The body shape varies from oval to round to elongated.
- Legs may be short or long and distinct. Claws and caruncles (suckers) may be present in some species.
- The location of the anus on the anal plate (a chitinous plate on the ventral surface) differs between species.
- Some mites, especially closely-related species, may be difficult or impossible to identify without the help of a trained entomologist or molecular testing.
- Identification keys and mite experts can be consulted for further details.
Endemic Mites of Animal Health Concern
The mites listed below are commonly found in the United States. In certain areas, these mites may transmit pathogens. Endemic diseases in animals may or may not be reportable, depending on the jurisdiction.
Daktaridudu, Wikimedia Commons, CC-BY-SA-4.0
Name: Cheyletiella spp. (C. parasitivorax, C. blakei, C. yasguri)
Characteristics: Microscopic, non-burrowing mite with large curved palpal hooks by its mouthparts, and feeds on skin debris
Domestic Animal Hosts: Rabbits, cats, dogs (low host specificity), highly contagious to humans
Health Impacts: Dermatitis (“walking dandruff”), itching, possible crusts, vector of myxoma virus (rabbits)
Daktaridudu, Wikimedia Commons, CC-BY-SA-4.0
Name: Chorioptes spp. (C. bovis)
Characteristics: Microscopic, non-burrowing mite with long legs and suckers that feeds on skin debris
Domestic Animal Hosts: Cattle, horses, sheep, goats, rabbits (low host specificity)
Health Impacts: Range of subclinical to mild itching to mange (particularly affecting the tail and lower legs)
Soolquipildor, iNaturalist, CC-BY-SA-4.0
Name: Demodex spp. (D. bovis, D. canis, D. equi)
Characteristics: Microscopic burrowing mite that is a normal inhabitant of hair follicles in many animals (causing disease when populations overgrow); elongated with short, stumpy legs
Domestic Animal Hosts: Multiple host-specific species (not zoonotic)
Health Impacts: Large pustules or nodules may occur in heavy infestations (cattle) or secondary infections
akt2, iNaturalist, CC-BY-SA-4.0
Name: Dermanyssus spp. (D. gallinae)
Characteristics: Non-burrowing mite with claw-like mouthparts, feeds at night and hides in crevices close to the roost/nest during the day
Domestic Animal Hosts: Poultry
Health Impacts: Decreased egg production, anemia, low weight gains, sometimes fatal if secondary infections, vector of fowl pox virus and several encephalitis-causing viruses
Daktaridudu, Wikimedia Commons, CC-BY-SA-3.0
Name: Notoedres spp. (N. cati)
Characteristics: Microscopic, round burrowing mite
Domestic Animal Hosts: Cats, rabbits, sometimes humans
Health Impacts: Severe itchiness with crusts, hair loss (particularly on the face and neck)
Kidneymoth, iNaturalist, CC-BY-SA-4.0
Name: Ornithonyssus spp. (O. sylviarum)
Characteristics: Non-burrowing, oval mite with whip-like mouthparts
Domestic Animal Hosts: Poultry (may also feed on mammalian hosts, including humans)
Health Impacts: Reduced egg production, anemia, irritation
Nicholas Winston Ong, iNaturalist, CC-BY-SA-4.0
Name: Otodectes spp. (O. cynotis)
Characteristics: Non-burrowing, oval mite commonly found in the ear canal but can be found in other parts of the body
Domestic Animal Hosts: Cats, dogs, and other animals
Health Impacts: Intense irritation in and around the ears
Daktaridudu, Wikimedia Commons, CC-BY-SA-4.0
Name: Psoroptes spp. (P. cuniculi)
Characteristics: Non-burrowing, large, oval mite commonly found in the ears of affected animals
Domestic Animal Hosts: Rabbits, horses, goats, other animals
Health Impacts: Otitis externa with crusting, intense itchiness, head shaking, head tilt, secondary infections
Alan R. Walker, Wikimedia Commons, CC-BY-SA-3.0
Name: Sarcoptes spp. (S. scabiei var bovis, ovis)
Characteristics: Microscopic, round, burrowing mite of the skin
Domestic Animal Hosts: Host-specific varieties affecting a wide range of mammalian hosts (humans can be infested with animal varieties but short-lived and self-limiting)
Health Impacts: Intense itchiness, thickened skin with large folds, zoonotic infections
Waugsberg, Wikimedia Commons, CC-BY-SA-3.0
Name: Varroa spp. (V. destructor, V. jacobsoni)
Characteristics: Round, reddish, non-burrowing mite of honey bees; larger and slower than Tropilaelaps
Domestic Animal Hosts: Honey bees
Health Impacts: Parasitic mite syndrome, deformed wing virus, slow bee paralysis virus, colony collapse
Foreign Mites of Animal Health Concern
The mites listed below are selected vectors of highly contagious, reportable, or foreign diseases of animals. Learn more about recognizing and reporting foreign vectors and FADs at CFSPH: FAD Prevention.
Alan R. Walker, Wikimedia Commons, CC-BY-SA-3.0
Name: Psoroptes ovis
Characteristics: Tiny, non-burrowing mite commonly found on the backs and flanks of hosts
Distribution: Global distribution, although has been eradicated from the U.S., Canada, Australia, Scandinavia, and New Zealand
Health Impacts: Affects cattle, sheep, and goats by causing exudative dermatitis with thick crusts and scabs, hair/wool loss, lichenification (thick and leathery skin), secondary infections, and possibly death
CSIRO, Wikimedia Commons, CC-BY-3.0
Name: Tropilaelaps spp. (T. clareae, T. mercedesae)
Characteristics: Fast-running, reddish-brown, non-burrowing mite of honey bees; about 1/3 the size of a Varroa mite and oval in shape
Distribution: Asia, Indonesia, and Papua New Guinea
Health Impacts: Affects honey bees by transmitting parasitic mite syndrome, deformed wing virus, and possibly colony collapse
Collection and Submission of Mites
- History and clinical signs can be helpful for presumptive diagnosis. However, mites of concern should be collected for identification to ensure effective control measures are used. Testing may be available to determine if pathogens are present.
- If visible, mites can be placed in a labeled, sealed, leak-proof container with 70-90% ethanol. Rubbing alcohol, hand sanitizer, or clear cocktail alcohol (80 proof or higher) will also work, if needed.
- If mites are suspected, specimens may be collected from affected areas through skin scrapes, hair plucks, and/or skin biopsies. Due to grooming behaviors of some animals, mites can sometimes be detected in fecal examinations.
- Take care to not crush mites before submission.
- Always label specimens with host, location collected from the body, and date of collection.
- For honey bee colonies, mites can usually be identified by collecting and submitting a sample of affected adults and brood comb. Detailed instructions can be found at USDA: Bee Research Laboratory.
- Laboratories and shipping companies may have specific instructions for you to follow.
For additional tips, visit How to Submit Vectors for Identification.
Control and Prevention of Mites
- Depending on the species, eliminating mite infestations may not be possible. However, mite populations can be managed by disrupting their life cycle. Specific methods of treatment and control vary depending on the type of mite and animal involved.
- For prompt detection and control, continuously monitor animals for mite infestations and frequently inspect animal housing areas for signs of mites.
- A variety of mite control products are available for animals, including injectable, pour-on, and sprays.
- Be sure to choose a product with an EPA registration number (topicals) or FDA (A)NADA number (orals and injectables).
- Read the product label carefully to make sure it is effective for the mite species and safe for the species and age of animal to be treated.
- Over-the-counter products may not always be effective. Some mite species are developing resistance to common chemicals. Veterinary guidance is recommended.
- Multiple consecutive treatments may be needed to prevent reinfestation of animals from the environment.
- Additional treatments, such as antibiotics, may be needed for secondary infections.
- Avoid moving mites from one site to another.
- Check animals closely for mites before movement.
- Quarantine, inspect, and monitor new and returning animals in a separate area.
- Clean and disinfect contaminated vehicles and other equipment before movement.
- Some pathogens that are spread by mites can be prevented through the use of vaccines, such as fowl pox and avian encephalomyelitis in poultry.
For additional guidance, visit Considerations When Managing Vectors.
Learn More
Additional information on mites, their impacts on animals, and control can be found below.
Endemic mites
Foreign mites
Note: This webpage shows some of the most significant vectors of concern to domestic animals in the United States. It is not meant to be a complete resource of all arthropods, their associated diseases and conditions, or used as a diagnostic tool. Veterinary consultation is advised for clinical cases.