Importance
- There are over 1,000 species of ticks worldwide. Only about 25 species are of concern to people or domestic animals.
- Ticks cause most vector-borne diseases reported each year in people and animals in the United States. Signs of tick-borne disease commonly include fever, lethargy, swollen or painful joints, and anemia.
- 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 tick-related FADs may include:
- Unfamiliar tick appearance
- Ticks present in unusually high numbers on an animal
- Large number of sick or dead animals
- Unusual signs of illness (like blisters or neurologic disease)
About Ticks
- Ticks are arachnids, relatives of spiders and mites.
- Hard ticks are the most common ticks affecting people and domestic animals. They have a four-stage life cycle (egg, larva, nymph, and adult) and usually live two to three years.
- Larvae, nymphs, and adult females of most tick species need a blood meal from a person or animal to continue their development. Some ticks are generalists with a wide host range, while others are specialists with a limited host range.
- Many tick species spend most of their life in wooded or grassy areas. Others live almost their entire life on one animal host.
- Ticks cannot jump or fly since they do not have wings. They do not travel far on their own without a host. Movement of ticks to new areas typically occurs through transporting animals infested with ticks.
Identification of Ticks
- Many tick species can be identified by a unique set of characteristics visible to the naked eye or with the help of a dissecting microscope.
- Some ticks, including engorged ticks, may be difficult or impossible to identify without the help of a trained entomologist or molecular testing.
- Ticks take on a different appearance at each life stage.
- Larvae are tiny (about the size of a speck of dirt) and have six legs.
- Nymphs are small (about the size of a freckle or poppy seed) and have eight legs.
- Adults are about the size of a sesame seed or larger and have eight legs. Males may look different from females.
- Unique characteristics can help differentiate tick species.
- The tick’s “head” (capitulum) is shaped differently from one tick genus to another.
- Mouthparts of nymphs and adult females are longer than adult males.
- The scutum (shield) often has distinctive colorings and markings (ornamentation). Adult females have a short scutum, which allows for large blood meals to be taken. Males have a scutum that reaches completely to the end of their body.
- Bumpy grooves or ridges (festoons) are present along the back edge of some species.
- Identification keys and tick experts can be consulted for further details.
Endemic Ticks of Animal Health Concern
The ticks listed below are commonly found in the United States. In certain areas, these ticks may transmit pathogens. Endemic diseases in animals may or may not be reportable, depending on the jurisdiction.
CDC Public Health Image Library/Lauren Bishop
Name: Amblyomma americanum (Lone Star Tick)
Characteristics: Dark brown scutum with white spot centrally located (females) or white streaks along the body edge (males), long mouthparts, and festoons
Distribution: Widely distributed in the southeastern and eastern U.S. (grassy and wooded areas)
Endemic Diseases:
Cytauxzoonosis
Ehrlichiosis
Rocky Mountain spotted fever (RMSF)
Tick paralysis
Tularemia
CDC Public Health Image Library/Dr. Christopher Paddock
Name: Amblyomma mixtum (formerly A. cajennense) (Northern Cayenne Tick)
Characteristics: Similar to lone star ticks but without a white spot on the scutum, tan to gold scutum with dark brown ornamentation, long mouthparts, and festoons
Distribution: Mostly southern Texas as well as the coastal region bordering the Gulf of Mexico (grassy and brushy areas)
Endemic Diseases:
Rocky Mountain spotted fever (RMSF)
CDC Public Health Image Library/James Gathany
Name: Amblyomma maculatum (Gulf Coast Tick)
Characteristics: Dark brown scutum with white linear lines, long mouthparts, and festoons
Distribution: Coastal areas along the Atlantic coast and the Gulf of Mexico (grassy, drier uplands)
Endemic Diseases:
American canine hepatozoonosis
Tick paralysis
Dustin Snider/inaturalist, CC BY 4.0
Name: Dermacentor albipictus (Winter Tick)
Characteristics: Reddish-brown in color with creamy white scutum, short mouthparts, and festoons
Distribution: Widely distributed throughout the U.S. (one-host tick that prefers moose and other ungulates)
Endemic Diseases:
Anaplasmosis
Tick paralysis
CDC Public Health Image Library/James Gathany
Name: Dermacentor andersoni (Rocky Mountain Wood Tick)
Characteristics: Dark brown scutum with whitish ornamentation, short mouthparts, and festoons (similar to D. variabilis)
Distribution: Higher elevations in western states, including the Rocky Mountains (grassy and lightly wooded, shrubby areas)
Endemic Diseases:
Anaplasmosis
Colorado tick fever
Rocky Mountain spotted fever (RMSF)
Tick paralysis
Tularemia
Georgia Southern University
Name: Dermacentor (formerly Anocentor) nitens (Tropical Horse Tick)
Characteristics: Yellowish-brown without ornamentation, short mouthparts, and festoons (similar to D. albipictus)
Distribution: Southern Texas and Florida (one-host tick that prefers the ears of equids)
Endemic Diseases:
Anaplasmosis
anameilike/inaturalist, CC BY-NC 4.0
Name: Dermacentor similis (Western American Dog Tick)
Characteristics: Dark brown scutum with whitish ornamentation, short mouthparts, and festoons (similar to D. variabilis)
Distribution: West of the Rocky Mountains (forest edges and open, grassy areas)
Endemic Diseases:
Ehrlichiosis
Rocky Mountain spotted fever (RMSF)
Tularemia
CDC Public Health Image Library/James Gathany
Name: Dermacentor variabilis (American Dog Tick)
Characteristics: Dark brown scutum with whitish ornamentation, short mouthparts, and festoons (similar to D. similis)
Distribution: Widely distributed east of the Rocky Mountains (grassy and lightly wooded, brushy areas)
Endemic Diseases:
Anaplasmosis
Rocky Mountain spotted fever (RMSF)
Tick paralysis
Tularemia
CDC Public Health Image Library/James Gathany
Name: Haemaphysalis longicornis (Asian Longhorned Tick)
Characteristics: Reddish-brown tick lacking ornamentation, small mouthparts, festoons, and lacking eyes
Distribution: Recently introduced, continuing to expand its distribution, and currently found in the Eastern states and central U.S. (grassy and wooded areas)
Endemic Diseases:
Bovine theileriosis
CDC Public Health Image Library/Drs. Amanda Loftis, William Nicholson, Will Reeves, Chris Paddock
Name: Ixodes pacificus (Western Blacklegged Tick)
Characteristics: Red tick with black scutum lacking ornamentation, long and narrow mouthparts, and no festoons (similar to I. scapularis)
Distribution: West coast of the U.S. (wooded and brushy areas)
Endemic Diseases:
Anaplasmosis
Lyme disease
CDC Public Health Image Library/Dr. Michael L. Levin
Name: Ixodes scapularis (Blacklegged or Deer Tick)
Characteristics: Red tick with black scutum lacking ornamentation, long and narrow mouthparts, and no festoons (similar to I. pacificus)
Distribution: Eastern and Upper Midwestern states (wooded and brushy areas)
Endemic Diseases:
Anaplasmosis
Bovine babesiosis
Cervid babesiosis
Ehrlichiosis
Lyme disease
Tick paralysis
Christian Schwarz, iNaturalist, CC BY-NC 4.0
Name: Ornithodoros coriaceus (Pajahuello Tick)
Characteristics: Soft tick that lacks a hard scutum and has mouthparts on the underside of its body
Distribution: Present in western U.S. at elevations of 600-8,000 feet (chaparral and oak tree habitat)
Endemic Diseases:
Foothill abortion (Epizootic Bovine Abortion)
CDC Public Health Image Library/James Gathany
Name: Rhipicephalus sanguineus group, including R. sanguineus sensu stricto (Brown Dog Tick)
Characteristics: Reddish-brown tick with elongated body lacking ornamentation, short mouthparts, hexagonal basis capitulum, and festoons
Distribution: Throughout the U.S. with higher populations in southern states (grassy and wooded areas, cracks and crevices in homes and dog kennels); common in urban settings where dogs or other domestic pets are abundant.
Endemic Diseases:
Anaplasmosis
Ehrlichiosis
Rocky Mountain spotted fever (RMSF)
Tick paralysis
Foreign Ticks of Animal Health Concern
The ticks listed below are selected vectors of highly contagious, reportable, or foreign diseases of animals. Learn more about recognizing and reporting foreign ticks and FADs at CFSPH: FAD Prevention.
Alan Walker/Wikimedia Commons, CC By-SA 3.0
Name: Amblyomma variegatum (Tropical Bont Tick)
Characteristics: Brown with bright yellow-orange ornamentation on scutum (males), large mouthparts, and festoons
Distribution: Tropics and subtropics (esp. Africa and Caribbean)
Foreign Diseases:
Dermatophilosis
Heartwater
Nairobi sheep disease
Holger Krisp/Wikimedia Commons, CC BY 3.0
Name: Ixodes ricinus (Castor Bean or Sheep Tick)
Characteristics: Red tick with black scutum lacking ornamentation, long and narrow mouthparts, and no festoons (similar to I. scapularis)
Distribution: Temperate zones (esp. Europe and northern Iran/Africa)
Foreign Diseases:
Louping ill
A.J.E. Terzi, Wikimedia Commons, CC BY 4.0
Name: Ornithodoros moubata (African Hut or Eyeless Tampan)
Characteristics: Soft tick with brown, leathery dorsum (no scutum), ventrally located head with no eyes and no suture line between the dorsal and ventral surfaces
Distribution: Tropics (esp. Africa)
Foreign Diseases:
African swine fever
Daktaridudu, Wikimedia Commons, CC-BY-SA-4.0
Name: Rhipicephalus (Boophilus) annulatus and microplus (Cattle Fever Ticks)
Characteristics: Brown, elongated tick lacking ornamentation with hexagonal basis capitulum, short mouthparts, and no festoons
Distribution: Permanent quarantine zone in southern Texas along Mexican border (as part of USDA’s Cattle Fever Tick Eradication Program); tropics and subtropics (esp. Mexico), large parts of Asia
Foreign Diseases:
Piroplasmosis
Collection and Submission of Ticks
- Prompt tick removal is critical since many pathogens require at least 12-24 hours of attachment to a person or animal to transmit disease.
- Inspect animals closely for ticks after being outdoors, paying close attention to areas in and around the ears, on the eyelids, behind the elbows, under the armpits, and under the base of the tail.
- To remove an attached tick, grasp it near skin (attachment point) with tweezers and gently pull straight up to keep the head and mouthparts (capitulum) intact.
- Ticks of concern should be collected for identification to ensure effective control measures are used. Testing may be available to determine if pathogens are present.
- Laboratories and shipping companies may have specific instructions for you to follow.
- Organisms should be dead before shipping. Ticks can be killed by freezing overnight or placing them in 70-90% ethanol.
- It is best to place ticks in a labeled, sealed, water-proof container. Alternatively, ticks may be double bagged inside sealable baggies (e.g., Ziploc® bags).
- Ticks can be preserved by submerging them in 70-90% ethanol. For shipping purposes, liquids may be avoided by placing a cotton ball soaked in ethanol, rubbing alcohol, or clear cocktail alcohol (80 proof or higher) alongside the tick in a container.
For additional tips, visit How to Submit Vectors for Identification.
Control and Prevention of Ticks
- While eliminating ticks is not likely, tick populations can be managed by disrupting the tick life cycle and habitat.
- For prompt detection and control, continuously monitor animals for tick infestations and frequently inspect animal housing areas (particularly areas near woods, shrubs, and tall grasses).
- Manage tick habitat to discourage tick migration and reduce tick encounters. Preventive measures may include frequent mowing and tree or brush removal within three feet of animal areas and trails.
- A variety of tick control products are available for treatment of animals, including oral chews, injectables, or topical pour-ons, sprays, and dips.
- 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 against the tick species and also safe for the species and age of animal to be treated.
- Environmental tick control products should be used only after consultation with experts to prevent unintended harm to wild animals and invertebrates, like frogs and honey bees. These products can also contaminate water sources.
- Researchers are currently exploring and assessing community-based tick control practices such as trail maintenance and insecticide treatment of wild animals.
- Avoid moving ticks from one site to another.
- Check animals and people closely for ticks after being in or near tick habitat and before movement.
- Remove ticks from affected clothing, equipment, and vehicles.
- Canine Lyme disease vaccines are commercially available and should be considered for preventing disease in dogs with tick exposure.
For additional guidance, visit Considerations When Managing Vectors.
Learn More
Additional information on ticks, their impacts on animals, and control can be found below.
Endemic ticks
Foreign ticks
Tick control for animals
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.