PARASITE PROTOCOLS FOR YOUR PRACTICE Peer Reviewed

Recommendations from the Companion Parasite Council FELINE FRIENDLY FELINE ARTICLE Lindsay Starkey, DVM Jay Stewart, DVM Oklahoma State University Aumsville Animal Clinic, Aumsville, Oregon

The mission of the Companion Animal Parasite Council (CAPC) is to foster animal and human health, while preserving the human–animal bond, through recommendations for the diagnosis, treatment, prevention, and control of parasitic infections. For more information, including detailed parasite control recommendations, please visit capcvet.org.

Ectoparasites—in addition to being a nuisance— 4. Adults quickly fi nd a host after emerging, and are associated with allergies, skin infections, and begin feeding within minutes.1 self-induced traumatic injury in pets. They are also • Egg production begins around 24 hours after vectors of infectious and zoonotic disease-causing initiation of feeding.1 agents, some of which can prove fatal.1–6 , • Adults account for only about 5% of the total , , and lice are common ectoparasites population in an infestation.12 seen on in the United States. Completion of the life cycle typically takes 3 to 8 weeks, and depends on relative humidity and FLEAS temperature; a moist, warm environment is ideal.4 The most common ectoparasite that infests cats (and ) in North America is the fl ea, Signi cance of Infestation Ctenocephalides felis ( ). Other fl eas also Figure 1 Fleas can cause irritation and pruritus, and certain infest cats, including gallinacea, Pulex cats may develop fl ea allergy dermatitis. Heavy irritans, and P simulans.1,7,8 infestations can lead to anemia and, if not managed appropriately, can be fatal.1 Life Cycle Fleas are also important vectors of disease- Fleas have 4 life stages: causing agents. They can transmit Dipylidium 1. Eggs are deposited by fed females and quickly caninum and bacteria that cause bartonellosis, fall into the environment; a female fl ea produces 40 to 50 eggs per day.9 hemotropic mycoplasmosis, rickettsiosis, plague, 2. Larvae hatch from eggs in 1 to 6 days.1 and tularemia; many of the aforementioned agents 5,6 • Food sources include organic debris (flea can infect humans as well. eggshells, adult flea feces) and other larval fleas.1 • Larvae develop in areas away from direct sunlight, including cool, shady areas outdoors, such as under porches or decks, and indoor locations, including carpet, furniture, and baseboards.1,4 3. Pupae develop from mature larvae.1 • Adults emerge from pupal casings in as little as 2 weeks or up to 6 months.1,10,11 • Emergence is stimulated by mechanical FIGURE 1. Adult Ctenocephalides felis. pressure, carbon dioxide, and increased Courtesy National Center for Veterinary Parasitology, Oklahoma State University temperature.10

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Treatment Strategies Eliminating fl ea infestations can TABLE 1. be challenging, and many factors Flea-Control Products Available for Cats in the U.S. 15 must be considered:12–14 INSECTICIDES TO KILL ADULT FLEAS • Killing the fleas on the patient Topical • Dinotefuran • Indoxacarb (1-month effi cacy) • Eliminating eggs, larvae, and • Etofenprox • Pyrethrins • Fipronil • pupae in the environment; as • Imidacloprid • Spinetoram these life stages mature, they Oral • Nitenpyram (Q 24 H or as needed) will continue to infest the pet • Spinosad (1-month effi cacy) • Identifying additional untreated Collar pets, feral , or peri- • Flumethrin (8-month effi cacy) • Imidacloprid domestic wildlife that contribute 15 to environmental contamination GROWTH REGULATORS & DEVELOPMENT INHIBITORS • Choosing products that address Topical • Methoprene (1-month effi cacy) difficult-to-treat life stages: • Pyriproxyfen Larvae and eggs may be located Oral (1-month effi cacy) • Lufenuron in hard-to-reach areas (eg, deep Injectable (6-month effi cacy) • Lufenuron within the carpet) and pupae can withstand many chemical Note that treatments. Implementation of an many drugs are formulated to treat integrated pest management ectoparasites, but strategy is often necessary to some that are safe resolve fl ea infestation:4,13 for use in or on 1. Routinely apply approved, dogs are not safe for use in cats due persistent fl ea-control products to potential adverse to every pet in the home year- effects, including round (Table 1):15 A B death. Follow label • Insecticides to kill the adult instructions carefully. fleas • Insect growth regulators and insect development inhibitors, which prevent maturation of immature flea stages 2. Treat the environment:4,14 • Mechanically remove immature stages by laundering flea-contaminated C D items and frequently FIGURE 2. Larva, nymph, and adults of Amblyomma americanum vacuuming (A); adults of Dermacentor variabilis (B) and Ixodes scapularis • Apply premise sprays to (C); and a nymph of megnini (D). Courtesy National Center for accelerate death of some Veterinary Parasitology, Oklahoma State University immature flea stages in the environment such as Rhipicephalus sanguineus, occasionally infest • Address sources of continued environmental cats.4,16-18 contamination. Life Cycle TICKS Life cycles differ greatly between hard and soft Ticks, although more common on dogs, can infest ticks. For hard ticks—A americanum, D variabilis, cats as well.16 The most common ticks found and I scapularis—3 different hosts are required to on cats in the U.S. are Amblyomma americanum, complete the life cycle:19 Dermacentor variabilis, Ixodes scapularis, and Otobius 1. A blood-engorged female deposits a single clutch megnini (Figure 2); however, other species, of thousands of eggs into the environment; from

60 TODAY’S VETERINARY PRACTICE | January/February 2015 | tvpjournal.com PARASITE PROTOCOLS FOR YOUR PRACTICE Peer Reviewed

TABLE 2. Common Feline Ticks: Geographic Distribution & Host/Environment Preferences TICK SPECIES GEOGRAPHIC DISTRIBUTION18,20,21 PREFERENCES18,19,21,22 A americanum Southeastern states; recently spread Hosts: White-tailed deer northward and eastward to include Environment: Leaf-littered wooded areas upper Midwest and New England states

D variabilis Eastern 2/3 of U.S. Hosts: Small vertebrates, including rodents/reptiles (immature stages); medium to large mammals (adults) Environment: Open areas with tall grass

I scapularis Eastern 2/3 of U.S. Hosts: Small vertebrates, including rodents/reptiles (immature stages); white-tailed deer (adults) Environment: Wooded areas O megnini South central and southwestern Hosts: Variety of mammals (immature stages) states Environment: Can withstand high-temperature, low- humidity areas

those eggs hatch 6-legged larvae that fi nd the Ticks are also important vectors of infectious fi rst host. agents: 2. Larvae attach and feed for a few days before • Borrelia burgdorferi, Anaplasma phagocytophilum, falling off and molting in the environment into and an Ehrlichia canis-like agent can infect cats 8-legged nymphs. Nymphs fi nd another host, (and humans), but their pathogenesis appears to feed for days to a week, detach, and fall into be minimal in cats.24,25 the environment, molting to the fi nal stage—8- • Infections with Cytauxzoon felis or Francisella legged adult male and female ticks. tularensis, both vectored by A americanum and D 3. Adult ticks fi nd hosts and feed for 1 to 2 weeks; variabilis, are far more severe diseases; both can engorged, mated females detach before laying cause death in cats.26-28 their egg clutch.23 For the soft tick—O megnini—only one host is Treatment Strategies required to complete its life cycle:18 Tick control, similar to fl ea control, can be 1. The female can lay several clutches of eggs in the challenging, and also requires an integrated pest environment. management strategy.18,19 2. When the larvae hatch, they obtain a host, CAPC recommends keeping cats indoors to crawling into the ear canal, feeding, and molting protect them not only from ticks but from other into the fi rst and second nymphal stages. parasitic infections. However, for cats that do 3. Second-stage nymphs crawl out of the ear canal venture outdoors, or those that share their living and enter the environment, molting into the spaces with dogs, control ticks by:18,19 nonparasitic adult stage; the adults mate off-host. 1. Using a tick-control product (acaricide) Geographic distribution and host preferences approved for cats, such as:15,18 differ among tick species (Table 2).18-22 • Topical (1-month effi cacy): etofenprox, fi pronil Signi cance of Infestation • Collar (8-month effi cacy): fl umethrin As seen with fl ea infestations, ticks are associated 2. Implementing environmental management with irritation, pruritus, anemia, and potential strategies:19 secondary bacterial skin infections; furthermore, • Limiting exposure to areas conducive to ticks due to the attachment and feeding practices of • Excluding wildlife from areas near the house most ticks, severe skin reactions at the bite site can • Manicuring lawns and removing brush piles occur.4,16-18,21 and leaf litter (“tick-scaping”) • O megnini exclusively infests the ears, resulting in • Applying acaricides to yard and perimeter. inflammation of the ear canal.23 • Attachment of D variabilis has been associated MITES with a paralytic condition that resolves upon tick Cats can be infested with several species; the removal.18 most common are Otodectes cynotis, Notoedres cati,

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A B FIGURE 3. Microscopic views of Otodectes cynotis, 200× magnifi cation (A) and gatoi, approximately 400× magnifi cation (B). Courtesy National Center for Veterinary Parasitology, Oklahoma State University

Demodex cati, and D gatoi (Figure 3). Cheyletiella household is necessary to prevent reinfestation; blakei, Lynxacarus radovskyi, and O cynotis also necessitates treatment of dogs and rarely infest cats in the U.S.3,16,29-31 ferrets.30 Decontamination of bedding and grooming supplies is also recommended because some mites Life Cycle may survive off-host for short periods.3,30 The generic mite life cycle involves eggs, larvae, 2 nymphal stages, and adults, and takes 3 to 4 weeks LICE to complete. All stages of mites can live in tunnels Lice are a rather uncommon fi nding in cats that burrowed through the skin, within hair follicles, or are receiving fl ea control; however, lice do infest on the surface of the host’s skin, but preferred sites cats on occasion, especially young, old, debilitated, of infestation depend on the species (Table 3).3,30,31 or neglected cats.3,16 Felicola subrostratus is the 3 Mites are transmitted between hosts by direct chewing of cats (Figure 4). contact with an infested animal. Life Cycle Signi cance of Infestation Completion of the louse life cycle takes 1 to 2 3,16,32 Infestation with mites generally results in local months: irritation and pruritus, but may progress to 1. The female lays many eggs throughout her life alopecia, exfoliative dermatitis, hyperkeratosis, or and cements them to the hair of the host. self-mutilation.17,29,31 2. A nymph hatches from the egg in 1 to 2 weeks; All of the feline mite species discussed—other nymphs feed on tissue debris and undergo 2 than Demodex species and L radovskyi—have been additional molts to become adults. 3. Adults also feed on tissue debris and mate while associated with transient infestations of humans.2,30 in the haircoat of the cat. Treatment Strategies Signi cance of Infestation Treatment of mite infestations is more Chewing lice attach at the base of the hair and straightforward than treatment of fl eas or ticks. • Topical heartworm preventives for cats (selamectin or moxidectin/imidacloprid) are labeled to treat TABLE 3. O cynotis; topical acaricides designed for use in Preferred Sites of Infestation by Mite Species the ear ( or milbemycin oxime) can MITE SPECIES PREFERRED SITE OF INFESTATION30,31 3,30 also be used to treat O cynotis. C blakei Dorsum • For other mite species that can infest D cati Face and neck cats, macrocyclic lactones or fipronil are D gatoi recommended; multiple doses are required to Abdomen and inside of upper hindlimbs treat most infestations.3,30,31 L radovskyi Perineal and tail areas • Addition of antibiotics may be necessary if a N cati Pinnae, face, and distal extremities secondary bacterial infection is present. O cynotis Ear canals Since mites are transmitted through direct S scabiei contact, treatment of all other cats in the Ears, elbows, and hocks

62 TODAY’S VETERINARY PRACTICE | January/February 2015 | tvpjournal.com PARASITE PROTOCOLS FOR YOUR PRACTICE Peer Reviewed

products are available for routine use in cats. Some products not only control the ectoparasites discussed in this article but also prevent or treat other parasitic infections.15 CAPC recommends broad-spectrum parasite control for every pet year-round; visit capcvet.org/resource -library for a comprehensive summary table of available ectoparasite control products for use in cats.

References FIGURE 4. Microscopic view of Felicola 1. Dryden MW, Rust MK. The cat fl ea: Biology, ecology, and subrostratus, 100× magnifi cation. Courtesy National control. Vet Parasitol 1994; 52(1-2):1-19. Center for Veterinary Parasitology, Oklahoma State University 2. Moriello KA. Zoonotic skin diseases of dogs and cats. Anim Health Res Rev 2003; 4(2):157-168. 3. Arther RG. Mites and lice: Biology and control. Vet Clin North are typically located around the head, neck, tail, Am Small Anim Pract 2009; 39(6):1159-1171. and body openings.3,33 Infestation can cause 4. Blagburn BL, Dryden MW. Biology, treatment, and control of fl ea and tick infestations. Vet Clin North Am Small Anim Pract 2009; irritation and pruritus, which can lead to rubbing, 39(6):1173-1200. scratching, and alopecia of the infested areas.3,16,33 5. McElroy KM, Blagburn BL, Breitschwerdt EB, et al. Flea- associated zoonotic diseases of cats in the USA: Bartonellosis, fl ea-borne rickettsioses, and plague. Trends Parasitol 2010; Treatment Strategies 26(4):197-204. Treatment of lice requires: 6. Eisen RJ, Gage KL. Transmission of fl ea-borne zoonotic agents. Annu Rev Entomol 2012; 57:61-82. • Use of an insecticide on the cat, including topical 7. Coles TB, Dryden MW. Insecticide/acaricide resistance in fl eas spot-on, shampoos, sprays, or powders; fipronil, and ticks infesting dogs and cats. Parasit Vectors 2014; 7:8. imidacloprid, and selamectin are effective at 8. Harman DW, Halliwell RE, Greiner EC. Flea species from dogs and cats in north-central Florida. Vet Parasitol 1987; 23(1-2):135-140. 16,32,33 killing lice. 9. Rust MK. Infl uence of photoperiod on egg production of cat • Treatment of all cats in the household because fl eas (Siphonaptera: ) infesting cats. J Med Entomol 1992; 29:242-245. lice are transmitted through direct contact with 10. Silverman J, Rust MK. Extended longevity of pre-emerged infested animals.16 adult cat fl ea (Siphonaptera: Pulicidae) and factors stimulating • Decontamination of bedding and grooming emergence from the pupal cocoon. Ann Entomol Soc Am 1985; 78:763-768. supplies—fomites on which eggs may be 11. Olsen A. Annual Report. Lyngby, Denmark: Danish Infestation located—by placing them in a clothes dryer for Laboratory, 1990, pp 59-60. 12. Halos L, Beugnet F, Cardoso L, et al. Flea control failure? Myths 3 several hours. and realities. Trends Parasitol 2014; 30(5):228-233. Lice are very species specifi c; there is no risk for 13. Siak M, Burrows M. Flea control in cats: New concepts and the current armoury. J Feline Med Surg 2013; 15(1):31-40. transmission of lice to humans or pets other than 14. Dryden MW, Payne P, Zurek L. Fleas infesting our pets and cats.16 homes. Kansas State University Agricultural Experiment Station and Cooperative Extension Service; September 2003. 15. Inglis S (ed). Compendium of Veterinary Products. Shawnee, KS: IN SUMMARY Bayer Corporation, 2014. There is no shortage of ectoparasites that cause 16. Dryden MW, Payne PA. Preventing parasites in cats. Vet Ther 2005; 6(3):260-267. disease in our feline patients, whether directly 17. Akucewich LH, Philman K, Clark A, et al. Prevalence of or indirectly. The diseases associated with these ectoparasites in a population of feral cats from north central Florida parasites can be quite severe in both cats and during the summer. Vet Parasitol 2002; 109(1-2):129-139. 18. Dryden MW, Payne PA. Biology and control of ticks infesting humans. Our clients want to protect their pets (and dogs and cats in North America. Vet Ther 2004; 5(2):139-154. themselves) from these parasitic invaders, and the 19. Stafford KC III. Tick Management Handbook. South Windsor, CT: The Connecticut Agricultural Experiment Station, 2007; available veterinary team is equipped with the knowledge at ct.gov/caes/lib/caes/documents/publications/bulletins/b1010. and tools to: pdf. • Educate clients about these parasites LINDSAY STARKEY JAY STEWART • Treat the current Lindsay Starkey, DVM, is the Bayer Jay Stewart, DVM, owns and operates infestation Resident in Veterinary Parasitology Aumsville Animal Clinic in Aumsville, at the National Center for Veterinary Oregon, where he enjoys both clinical • Implement strategies Parasitology, Oklahoma State University and management responsibilities in to prevent future (ncvetp.org). Dr. Starkey received her his multi-doctor small animal practice. DVM from Oklahoma State University. Dr. Stewart received his DVM from infestations. Colorado State University. Many safe and effective

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20. Centers for Disease Control and Prevention. Ticks: Geographic distribution. Available at cdc.gov/ticks/geographic_distribution.html. 21. Berrada ZL, Telford SR III. Burden of tick-borne infections on American companion animals. Top Companion Anim Med 2009; 24(4):175-181. 22. Childs JE, Paddock CD. The ascendancy of Amblyomma americanum as a vector of pathogens affecting humans in the United States. Annu Rev Entomol 2003; 48:307-337. 23. American Association of Veterinary Parasitologists. . Available at aavp.org/wiki/arthropods/arachnids/ metastigmata//Otobius-megnini/. 24. Breitschwerdt EB, Abrams-Ogg A, Lappin MR, et al. Molecular evidence supporting Ehrlichia canis-like infection in cats. J Vet Intern Med 2002; 16:642-649. 25. Magnarelli LA, Bushmich SL, Ijdo JW, et al. Seroprevalence of antibodies against Borrelia burgdorferi and Anaplasma phagocytophilum in cats. Am J Vet Res 2005; 66:1895-1899. 26. Blouin EF, Kocan AA, Glenn BL, et al. Transmission of Cytauxzoon felis (Kier, 1979) from bobcats, Felis rufus (Schreber), to domestic cats by Dermacentor variabilis (Say). J Wildl Dis 1984; 20(3):241-242. 27. Petersen JM, Mead PS, Schriefer ME. Franscisella tularensis: An -borne pathogen. Vet Res 2009; 40(2):7. 28. Reichard MV, Meinkoth JH, Edwards AC, et al. Transmission of Cytauxzoon felis to a domestic cat by Amblyomma americanum. Vet Parasitol 2009; 161(1-2):110-115. 29. Craig TM, Teel PD, Dubuisson LM, Dubuisson RK. Lynxacarus radovskyi infestation in a cat. JAVMA 1993; 202(4):613-614. 30. Curtis CF. Current trends in the treatment of Sarcoptes, Cheyletiella, and Otodectes mite infestation in dogs and cats. Vet Dermatol 2004; 15(2):108-114. 31. Beale K. Feline : A consideration in the itchy or overgrooming cat. J Feline Med Surg 2012; 14(3):209-213. 32. Shanks DJ, Gautier P, McTier TL, et al. Effi cacy of selamectin against biting lice on dogs and cats. Vet Rec 2003; 152(8):234-237. 33. Pollmeier M, Pengo G, Longo M, Jeannin P. Effective treatment and control of biting lice, Felicola subrostratus (Nitzsch in Burmeister, 1838), on cats using fi pronil formulations. Vet Parasitol 2004; 121(1-2):157-165.

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