Animal Bite

7/29/2019 Animal Bite

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Animal Bites in Emergency Medicine Follow-upM. Yusuf, MD

BackgroundBecause many animal bites are never reported, determining the exact incidence of bite wounds in theUnited States, let alone the world, is difficult. An estimated 74.8 million dogs lived in the United Statesin 2007; these account for an estimated 5 million dog bites per year, over which 800,000 requiremedical attention[1] . Substantially more dog bites occur than cat bites. These two species account forthe majority of (non-human) mammalian bite wounds encountered in the emergency department (ED).

Patophysiology

Dog bites typically cause a crushing-type wound because of their rounded teeth and strong jaws. Anadult dog can exert 200 pounds per square inch (psi) of pressure, with some large dogs able to exert450 psi.[2] Such extreme pressure may damage deeper structures such as bones, vessels, tendons,muscle, and nerves.

A bite from a pit bull is shown below.

Animal bites. Wounds to the left arm and hip inflicted during a dog attack.

The sharp pointed teeth of cats usually cause puncture wounds and lacerations that may inoculatebacteria into deep tissues. Infections caused by cat bites generally develop faster than those of dogs.[3, 4]

Limited literature is available on other mammalian bites. Monkey bites have a notorious reputationbased largely on anecdotal reports. Several cases of unprovoked attacks on young children and

infants by domesticated ferrets have been documented. The bites of foxes, raccoons, skunks, bats,dogs, and cats have been clearly linked to rabies exposure. Bites from large herbivores generallyhave a significant crush element because of the force involved.

Bites of the hand generally have a high risk for infection because of the relatively poor blood supply ofmany structures in the hand and anatomic considerations that make adequate cleansing of the wounddifficult. In general, the better the vascular supply and the easier the wound is to clean (ie, lacerationvs puncture), the lower the risk of infection.

A major concern in all bite wounds is subsequent infection. Infections can be caused by nearly anygroup of pathogens (bacteria, viruses, rickettsia, spirochetes, fungi). At least 64 species of bacteriaare found in the canine mouth, causing nearly all infections to be mixed.[5, 6, 7] Common bacteriainvolved in bite wound infections include the following:

Dog biteso Staphylococcus species

o Streptococcus species

o Eikenella species

o Pasteurella species

o Proteus species

o Klebsiella species

o Haemophilus species

o Enterobacterspecies

o DF-2 orCapnocytophaga canimorsus

o Bacteroides species

o Moraxella species

o Corynebacterium species

o Neisseria species
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o Fusobacterium species

o Prevotella species

o Porphyromonas species

Cat biteso Pasteurella species

o Actinomyces species

o Propionibacterium species



o Clostridium species

o Wolinella species

o Peptostreptococcus species

o Staphylococcus species


Herbivore biteso Actinobacillus lignieresii

o Actinobacillus suis

o Pasteurella multocida

o Pasteurella caballi

o Staphylococcus hyicus subsp hyicus

Swine biteso Pasteurella aerogenes

o Pasteurella multocida


o Proteus species

o Actinobacillus suis


o Flavobacterium species

o Mycoplasma species

Rodent bites - Rat-bite fevero Streptobacillus moniliformis

o Spirillum minus

Primateso Bacteroides species


o Eikenella corrodens


o Enterococcus species

o Staphylococcus species

o Enterobacteriaceae

o Simian herpes virus

Large reptiles (crocodiles, alligators)o Aeromonas hydrophila

o Pseudomonas pseudomallei

o Pseudomonas aeruginosa

o Proteus species

o Enterococcus species

o Clostridium species

Epidemiology

Frequency

United States

Of an estimated 3-6 million animal bites per year in the United States,[8]

approximately 80-90% arefrom dogs, 5-15% are from cats, and 2-5% are from rodents, with the balance from other smallanimals (eg, rabbits, ferrets), farm animals, monkeys, reptiles, and others. Some estimate that 1% of


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emergency visits are for dog bite wounds. Approximately 1% of dog bite wounds and 6% of cat bitewounds require hospitalization.[1, 9]

International

The lack of standard reporting in many countries makes accurate estimates of mammalian biteincidence difficult to determine. Depending on locale, the range of animals inflicting bites is wide and

includes large cats (tigers, lions, leopards), wild dogs, hyenas, wolves (Eurasia), crocodiles, and otherreptiles. As in the United States, most bites, however, are from domestic dogs. In developingcountries, mammalian bites (especially bites by dogs, cats, foxes, skunks, and raccoons) carry a highrisk of rabies infection.

Mortality/Morbidity

Dog attacks kill approximately 20-35 people annually in the United States.[8, 10, 11]Many of thesefatalities, unfortunately, are young children. While local infection and cellulitis are the leading causesof morbidity, sepsis is a potential complication of bite wounds, particularly C canimorsus (DF-2) sepsisin immunocompromised individuals. Pasteurella multocida infection (the most common pathogencontracted from cat bites) also may be complicated by sepsis.Meningitis,osteomyelitis,tenosynovitis,abscesses, pneumonia, endocarditis, andseptic arthritis are additional concerns in bite wounds. Whenrabies occurs, it is almost uniformly fatal (Rabies).

Sex

Women are more frequently bitten by cats, whereas men are more often bitten by dogs (despite beingman's best friend).[12]

Age

Peak incidence of animal bites occurs among children aged 5-9 years. [9, 8, 10]

HistoryHistory for animal bites should include the following:

Time and location of event

Type of animal and its status (ie, health, rabies vaccination history, behavior, whereabouts)

Circumstances surrounding the bite (ie, provoked or defensive bite versus unprovoked bite)

Location of bites (most commonly on the upper extremities and face)

Prehospital treatment

Patients medical history (immunocompromise, peripheral vascular disease, diabetes, tetanusand rabies vaccination history)

Major resuscitation rarely is required. Because patients typically are children, reassurance andparental presence may facilitate examination. Where applicable, consider the following:

Distal neurovascular status

Tendon or tendon sheath involvement

Bone injury, particularly of the skull in infants and young children

Joint space violation

Visceral injury

Foreign bodies (eg, teeth) in the woundSignificant damage due to bites is shown in the images below
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Animal bites. The devastating damage sustained by a preadolescent male during a dog attack. Almost lost in this

photograph is the soft tissue damage to this victim's thigh. This patient required 2 units of O- blood and several liters of

isotonic crystalloid. Repair of these wounds required a pediatric surgeon, an experienced orthopedic surgeon, and a

plastic surgeon. Attacks such as these have caused a movement in some areas of the country to ban certain dog

breeds.


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Animal bites. Massive soft tissue damage of the right leg caused by a dog attack. This patient was transferred to a level

one pediatric trauma center for care. At times, staff members may need counseling after caring for mauled patients.


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Animal bites. Massive soft tissue damage of the lower left leg caused from a dog attack. Most of the fatalities from dog

bites are children.


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Animal bites. A different angle of the patient in Image 3 showing the massive soft tissue damage to this child's left lower

leg.


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Animal bites. Wounds to the left arm and hip inflicted during a dog attack

Bite wounds from cats and dogs can occur without provocation, but provoked bites, such as disturbinganimals while they are eating, are more common. Older animals often are less tolerant ofdisturbances, especially by children. Most dog bites involve a dog that belongs to the family or friendof the victim and approximately half occur on the pet owner's property. [10]

Certainly, unprovoked bites by wild or sick-appearing animals (most notably by dogs, cats, raccoons,foxes, skunks, and bats) further raise underlying concerns about likelihood of rabies exposure.

Differential Diagnoses Bites, Human

Cellulitis

Fractures, Cervical Spine

Hand Infections

Neck Trauma

Osteomyelitis

Rabies

Tetanus

Laboratory StudiesFresh bite wounds without signs of infection do not need to be cultured. Infected bite wounds shouldbe cultured to help guide future antibiotic therapy.

Other laboratory tests are indicated as the patient's condition dictates (eg, CBC and blood cultures forpatients with sepsis).
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IfC canimorsus sepsis is suspected, examine the peripheral smear for the organism, a bacillus.

Imaging StudiesRadiography is indicated if any concerns exist that deep structures are at risk (eg, hand wounds; deeppunctures; crushing bites, especially over joints).

Occult fractures or osteomyelitis may be discovered.

Radiographs may find foreign bodies in the wound (eg, teeth).

Children who have been bitten in the head should be examined for bony penetration with plain films orCT scan. If the child was shaken, consider cervical spine evaluation.

Prehospital CareObtaining the history of the bite event is of major importance, including home treatment of wounds,body parts involved, and other symptoms (see History).

Rinse bite wounds, if possible, and cover with a sterile dressing. Tap water has been shown to be aseffective for irrigation as sterile saline.[13]

Encourage patients to seek prompt care.

Emergency Department CareMost bite wounds can be treated in the ED. Essentials of treatment are inspection, debridement,irrigation, and closure, if indicated. Complete trauma evaluation occasionally is indicated.

Carefully inspect bite wounds to identify deep injury and devitalized tissue. Obtaining anadequate inspection of a bite wound without it first being anesthetized is nearly impossible. Careshould be taken to visualize the bottom of the wound and, if applicable, to examine the woundthrough a range of motion.

Debridement is an effective means of preventing infection. Removing devitalized tissue,

particulate matter, and clots prevents these from becoming a source of infection, much like anyforeign body. Clean surgical wound edges result in smaller scars and promote faster healing.

Irrigation is another important means of infection prevention. A 19-gauge blunt needle and a35-mL syringe provide adequate pressure (7 psi) and volume to clean most bite wounds. In general,100-200 mL of irrigation solution per inch of wound is required.[13] Heavily contaminated bite woundsrequire more irrigation. Large dirty wounds may require irrigation in the operating room. Isotonicsodium chloride solution is a safe, available, effective, and inexpensive irrigating solution. Few of thenumerous other solutions and mixtures of saline and antibiotics have any advantages over saline. Ifa shieldlike device is used, take care to prevent the irrigating solution from returning to the wound,which decreases the effectiveness of the irrigation.

Primary closure may be considered in limited bite wounds that can be cleansed effectively(this excludes puncture wounds, ie, cat bites). Other wounds are best treated by delayed primaryclosure. Facial wounds, because of the excellent blood supply, are at low risk for infection, even if

closed primarily, but the risk of superinfection must be discussed with the patient prior to closure.Bite wounds to the hands and lower extremities, with a delay in presentation, or inimmunocompromised hosts, generally should be left open.[7]

If a bite wound involves the hand, consider immobilizing in a bulky dressing or splint to limituse and promote elevation.

Consider tetanus and rabies prophylaxis for all wounds. Antirabies treatment may be indicated forbites by dogs and cats whose rabies status can not be obtained, or in foxes, bats, raccoons, orskunks in the Americas (see Rabies and Tetanusfor treatment and dosing information).

Oehler et al have established a wound management strategy following animal bites to prevent severecomplications that include the following steps:[14]

Culture for aerobes and anaerobes if abscess, severe cellulitis, devitalized tissue, or sepsis is

present. Use saline solution for wound irrigation.
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Debride necrotic tissue and remove any foreign bodies.

If fracture or bone penetration, radiography is indicated (MRI or CT may also be indicated).

Initiate prophylactic antibiotics in selected cases (based on type and specific animal involved).

If methicillin-resistant Staphylococcus aureus (MRSA) is suspected, first-line antibioticsinclude trimethoprim-sulfamethoxazole, doxycycline, minocycline, and clindamycin.

Hospitalization is indicated if fever, sepsis, spreading cellulitis, severe edema, crush injury, or

loss of function is present. Also consider hospitalization for patients who are immunocompromisedor are likely to be noncompliant.

Administer tetanus booster (if none given in past year) or initiate primary series innonvaccinated individuals (See Tetanusfor further recommendations).

Assess the need for rabies vaccine and immunoglobulin (See Rabies for furtherrecommendations).

ConsultationsExtensive wounds, those involving tissue loss, or those involving complex structures may requireplastic surgery consultation.

If the skull is penetrated, neurosurgery consultation is indicated.

Local public health authorities should be notified of all bites and may help with recommendations forrabies prophylaxis.

Medication SummaryThis is one of most controversial subjects in wound care. Remember that proper wound care(inspection, debridement, irrigation, closure, if indicated) reduces infection more than antibiotics. Ingeneral, low-risk wounds do not require prophylactic antibiotics. However, therapy is recommendedfor high-risk wounds (eg, cat bites that are a true puncture, bites to the hand, massive crush injury,late presentation, poor general health).[15]

The goal of initial therapy is to cover staphylococci, streptococci, anaerobes, andPasteurella species.Prophylactic antibiotics may be given for a 3- to 5-day course. The first-line oral therapy is amoxicillin-clavulanate. For higher risk infections, a first dose of intravenous antibiotic may be given (ie,ampicillin-sulbactam, ticarcillin-clavulanate, piperacillin-tazobactam, or a carbapenem). Othercombinations of oral therapy include cefuroxime plus clindamycin or metronidazole, a fluoroquinoloneplus clindamycin or metronidazole, sulfamethoxazole and trimethoprim plus clindamycin ormetronidazole, penicillin plus clindamycin or metronidazole, amoxicillin plus clindamycin ormetronidazole and less effective azithromycin or doxycycline plus clindamycin or metronidazole.[16, 6, 7] Ifthe wound is infected on presentation, a course of 10 days or longer is recommended.

For monkey bites, postexposure prophylaxis valacyclovir or acyclovir should be given for 14 days.

Antibiotics

Class Summary

Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens in thecontext of the clinical setting.

View full drug information

Levofloxacin

For pseudomonal infections and infections due to multidrug resistant gram-negative organisms.


Metronidazole
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Imidazole ring-based antibiotic active against various anaerobic bacteria and protozoa. Used incombination with other antimicrobial agents (except forC difficile enterocolitis).


Ampicillin and sulbactam (Unasyn)

Drug combination of beta-lactamase inhibitor with ampicillin. Interferes with bacterial cell wallsynthesis during active replication, causing bactericidal activity against susceptible organisms.


Ticarcillin and clavulanate potassium (Timentin)

Inhibits biosynthesis of cell wall mucopeptide and is effective during stage of active growth.Antipseudomonal penicillin plus beta-lactamase inhibitor that provides coverage against most gram-positive organisms, most gram-negative organisms, and most anaerobes.


Piperacillin and tazobactam sodium (Zosyn)

Antipseudomonal penicillin plus beta-lactamase inhibitor. Inhibits biosynthesis of cell wallmucopeptide and is effective during stage of active multiplication.


Imipenem and cilastatin (Primaxin)

For treatment of multiple organism infections in which other agents do not have wide-spectrum

coverage or are contraindicated due to potential for toxicity.View full drug information

Ertapenem (Invanz)

Bactericidal activity results from inhibition of cell wall synthesis and is mediated through ertapenembinding to penicillin-binding proteins. Stable against hydrolysis by a variety of beta-lactamasesincluding penicillinases, cephalosporinases, and extended-spectrum beta-lactamases. Hydrolyzed bymetallo-beta-lactamases.


Meropenem (Merrem IV)

Bactericidal broad-spectrum carbapenem antibiotic that inhibits cell-wall synthesis. Effective againstmost gram-positive and gram-negative bacteria.

Has slightly increased activity against gram-negatives and slightly decreased activity againststaphylococci and streptococci compared to imipenem.


Amoxicillin and clavulanate (Augmentin)

Drug combination that extends antibiotic spectrum of penicillin to include bacteria normally resistant tobeta-lactam antibiotics. Indicated for skin and skin structure infections caused by beta-lactamaseproducing strains ofStaphylococcus aureus.
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Cefuroxime (Ceftin, Kefurox, Zinacef)

Second-generation cephalosporin maintains gram-positive activity that first-generation cephalosporinshave; adds activity against P mirabilis, H influenzae, E coli, K pneumoniae, and Mcatarrhalis. Condition of patient, severity of infection, and susceptibility of microorganism determineproper dose and route of administration.


Ciprofloxacin (Cipro)

Fluoroquinolone with activity against pseudomonads, streptococci, MRSA, S epidermidis, and mostgram-negative organisms, but no activity against anaerobes. Inhibits bacterial DNA synthesis and,consequently, growth.


Clindamycin (Cleocin)

Lincosamide for treatment of serious skin and soft tissue staphylococcal infections. Also effectiveagainst aerobic and anaerobic streptococci (except enterococci). Inhibits bacterial growth, possibly byblocking dissociation of peptidyl tRNA from ribosomes, causing RNA-dependent protein synthesis toarrest.


Sulfamethoxazole/trimethoprim (Bactrim, Bactrim DS, Septra, Septra DS)

Inhibits bacterial growth by inhibiting synthesis of dihydrofolic acid.


Amoxicillin (Trimox, Biomox, Amoxil)

Alone, this drug is effective against Pasteurella species. However, not indicated for skin and skinstructure infections caused by beta-lactamaseproducing strains ofStaphylococcus aureus. A secondantibiotic such as cephalexin is needed forStaphylococcus infections.


Azithromycin (Zithromax)

Inhibits bacterial growth, possibly by blocking dissociation of peptidyl tRNA from ribosomes, causingRNA-dependent protein synthesis to arrest. Treats mild-to-moderate microbial infections


Doxycycline (Doryx, Vibramycin, Bio-Tab)

Inhibits protein synthesis and thus bacterial growth by binding to 30S and possibly 50S ribosomalsubunits of susceptible bacteria.

Antiviral agentsClass Summary
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These agents inhibit viral replication.


Acyclovir (Zovirax)

Prodrug activated by phosphorylation by virus-specific thymidine kinase that inhibits viral replication.Herpes virus thymidine kinase (TK), but not host cells' TK, uses acyclovir as a purine nucleoside,converting it into acyclovir monophosphate, a nucleotide analogue. Guanylate kinase converts themonophosphate form into diphosphate and triphosphate analogues that inhibit viral DNA replication.

Has affinity for viral thymidine kinase and, once phosphorylated, causes DNA chain termination whenacted on by DNA polymerase. Has activity against a number of herpesviruses, including herpes virusB. Primarily available in preparations for PO and IV use. Patients experience less pain and fasterresolution of cutaneous lesions when used within 48 h from rash onset. May prevent recurrentoutbreaks. Early initiation of therapy is imperative.


Valacyclovir (Valtrex)

Hydrochloride salt of the L-valyl ester of acyclovir. Rapidly converted into acyclovir after promptabsorption from the gut via first-pass intestinal or hepatic metabolism. An alternative to acyclovir forprophylaxis (or possibly treatment).

ToxoidsClass Summary

Tetanus results from elaboration of an exotoxin from Clostridium tetani. A booster injection inpreviously immunized individuals is recommended to prevent this potentially lethal syndrome. Patientswho may not have been immunized against C tetaniproducts (eg, immigrants, the elderly) should

receive tetanus immune globulin.


Tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap, Adacel,

Boostrix)

Promotes active immunity to diphtheria, tetanus, and pertussis by inducing production of specificneutralizing antibodies and antitoxins. Indicated for active booster immunization for tetanus,diphtheria, and pertussis prevention for persons aged 10-64 y (Adacel approved for 11-64 y, Boostrixapproved for 10-18 y). Preferred vaccine for adolescents scheduled for booster.

Tetanus toxoid

No longer available in the United States.

Used to induce active immunity against tetanus in selected patients. The immunizing agent of choicefor most adults and children > 7 years are tetanus and diphtheria toxoids. Necessary to administerbooster doses to maintain tetanus immunity throughout life.

The CDC recommends Td for pregnant patients who have urgent indication tor tetanus toxoid ordiphtheria toxoid vaccination.

In children and adults, may administer into deltoid or midlateral thigh muscles. In infants, preferredsite of administration is the mid-thigh laterally.

Immune Globulin
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Class Summary

Indicated in previously unvaccinated individuals to provide passive immunity to tetanus whenindividuals become exposed.


Tetanus immune globulin (HyperTET S/D)

Used for passive immunization of any person with a wound that might be contaminated with tetanusspores.


Rabies Immune Globulin (Imogam Rabies-HT, HyperRab S/D)

Provides passive protection to individuals exposed to rabies virus. About 1/2 the dose should beadministered into and around the bite wound as much as possible (given anatomic constraints), andthe rest given intramuscularly at a site remote from the vaccine administration area in the gluteal ordeltoid muscle.

Vaccine, Inactivated VirusClass Summary

Inactivated forms of virus that promote immunity by inducing an active immune response.


Rabies vaccine (Rabavert, Imovax Rabies Vaccine)

Inactivated form of virus grown in primary cultures of chicken fibroblasts; offers active immunity and,when used in combination with human rabies immune globulin (HRIG) and local wound treatment,protects postexposure patients of all age groups; also used for preexposure immunization in bothprimary series and booster dose.

Fourteen days after initiating immunization series, anti-rabies antibody titers reach levels well aboveminimal protective level of 0.5 IU/mL.

Vaccine must be injected IM and never SC, ID, or IV. In adults, inject into deltoid muscle area. Insmall children, administer into anterolateral zone of thigh.

Rabies vaccine adsorbed (RVA; BioPort Corp under US Department of Defense contract

for military use only)

Inactivated virus vaccine, which promotes immunity by inducing active immune response. May begiven IM only, never ID.

Follow Up

Further Inpatient CarePatients with infected animal bites may need inpatient care. This depends on the general health of thepatient, the extent and nature of the infection, and the patient's compliance.

Consider admitting patients with hand bites that become infected (generally involving deep

structures). Consider consultation with hand surgery service if deep infection, such as involving thetendon sheath or other structures, is suspected as surgical irrigation may be indicated.
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Further Outpatient CareClose follow-up care is essential in animal bite wounds. Reevaluate a low-risk bite for signs ofinfection within 48 hours and a high-risk bite within 24 hours.

In some centers that have an observation unit, admission to that area for direct clinical observation

and repeat doses of parenteral antibiotics can be considered on a case-by-case basis.

TransferPatients who require extensive repair or prolonged inpatient care may need transfer to a tertiary carefacility.

ComplicationsComplications of bite wounds may include the following:

Wound infection

Sepsis

Cosmetic deformity

Loss of limb Loss of function

PrognosisThe prognosis of animal bite wounds is generally excellent.

Patient Education

Educating patients about the risk of infection despite proper wound care, antibiotics (if indicated), andclose follow-up care is very important. Even bite wounds that have received the best care maybecome infected. Teach patients the signs of infection and the need for prompt attention if the woundshould become infected.

For patient education resources, see the Bites and Stings Centerand Bacterial and Viral InfectionsCenter, as well asAnimal Bites and Rabies.

References

1. Centers for Disease Control and Prevention. Nonfatal dog bite-related injuries treated inhospital emergency departments--United States, 2001. MMWR Morb Mortal Wkly Rep. Jul 42003;52(26):605-10. [Medline].
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2. Chambers GH, Payne JF. Treatment of dog bite wounds. Minn Med. 1969;52:427-430. [Medline].

3. Freer L. Bites and injuries inflicted by wild and domestic animals. In: Auerbach PS,ed. Wilderness Medicine. 5th ed. Mosby; 2007:1133-55.

4. Dire DJ. Cat bite wounds: risk factors for infection.Ann Emerg Med. Sep 1991;20(9):973-9.[Medline].

5. Talan DA, Citron DM, Abrahamian FM, et al. Bacteriologic analysis of infected dog and catbites. N Engl J Med. Jan 14 1999;340(2):85-92.[Medline].

6. Abrahamian FM. Dog Bites: Bacteriology, Management, and Prevention. Curr Infect Dis Rep.Oct 2000;2(5):446-453.[Medline].

7. Stevens DL, Bisno AL, Chambers HF, et al. Practice guidelines for the diagnosis andmanagement of skin and soft-tissue infections. Clin Infect Dis. Nov 15 2005;41(10):1373-406. [Medline].

8. Gilchrist J, Sacks JJ, White D, Kresnow MJ. Dog bites: still a problem?. Inj Prev. Oct2008;14(5):296-301.[Medline].

9. Weiss HB, Friedman DI, Coben JH. Incidence of dog bite injuries treated in emergencydepartments.JAMA. Jan 7 1998;279(1):51-3.[Medline]. [Full Text].

10. Sacks JJ, Lockwood R, Hornreich J, Sattin RW. Fatal dog attacks, 1989-1994. Pediatrics. Jun1996;97(6 Pt 1):891-895.[Medline].

11. Animal People. Dog attack deaths and maimings, US and Canada. September 1982 toDecember 26, 2011. Dogsbite.org. Available athttp://www.dogsbite.org/pdf/dog-attack-deaths-maimings-merritt-clifton-2011.pdf. Accessed May 9, 2012.

12. Palacio J, Leon-Artozqui M, Pastor-Villalba E, Carrera-Martin F, Garcia-Belenguer S.

Incidence of and risk factors for cat bites: a first step in prevention and treatment of felineaggression. J Feline Med Surg. Jun 2007;9(3):188-95. [Medline].

13. Moscati RM, Mayrose J, Reardon RF, Janicke DM, Jehle DV. A multicenter comparison of tapwater versus sterile saline for wound irrigation.Academic Emergency Medicine. May 2007;14(5):404-9.[Medline].

14. Oehler RL, Velez AP, Mizrachi M, Lamarche J, Gompf S. Bite-related and septic syndromescaused by cats and dogs. Lancet Infect Dis. Jul 2009;9(7):439-47.

15. Cummings P. Antibiotics to prevent infection in patients with dog bite wounds: a meta-analysis of randomized trials.Ann Emerg Med. Mar 1994;23(3):535-40. [Medline].

16. Gilbert DN, Moellering RC, Eliopoulos FM, Sande MA, eds. Bites. In: The Sanford Guide toAntimicrobial Therapy. 37th ed. 2007:46,47,140.

17. Guy RJ, Zook EG. Successful treatment of acute head and neck dog bite wounds withoutantibiotics.Ann Plast Surg. Jul 1986;17(1):45-8. [Medline].

18. Trott A. Bite wounds. In: Wounds and Lacerations Emergency Care and Closure. 2nd ed. StLouis, Mo: Mosby-Year Book Inc; 1997:265-84.

19. Weber EJ. Mammalian bites. In: Marx JA, Hockberger RS, Walls RM, eds. Rosen'sEmergency Medicine: Concepts and Clinical Practice. 6th ed. Mosby; 2006:906-21.
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