Bites and Stings at a Glance
- Dog bites account for 80%–90% of all mammalian bites involving humans, but cat bites are more likely to become infected.
- Whether or not postexposure prophylaxis with rabies immunoglobulin and human diploid cell rabies vaccine is needed depends on the circumstances surrounding the bite.
- In the United States, there are approximately five to six deaths from snakebites and probably 6,000 to 7,000 snakebite envenomations each year.
- Most stingray injuries occur when bathers, waders, or fishermen accidentally step on rays as they lie partially covered with sand in shallow waters. The extreme pain caused by the venom may be relieved by soaking the affected body part in very warm water.
Humans are a part of the environment and ideally live peacefully with other animals and plants. However, sometimes the interactions between man and the environment prove harmful to one or the other. The first two sections of this chapter consider the harmful effects of land-borne animal bites, as well as the bacterial and viral infections they may transmit. The last section reviews bites and stings and other forms of injury that may be inflicted by marine life.
Dog bites account for 80%–90% of all mammalian bites involving humans. Four to five million dog bites are estimated to occur each year in the United States, and, in 2001, it was estimated that 368,245 persons were treated for dog bite-related injuries.1 The human victim is often a 5– 9-year-old boy who may have been teasing or playing with the dog. Sometimes the bite occurs when a person is trying to break up a pair of fighting dogs or trying to aid an animal. In the United States 4%–5% of dog bites are work related and include bites sustained by postal carriers. Overseas, a higher percentage are produced by untamed animals.2–4 Most dog bite injuries involve the upper extremities, especially the hands. Cat bites are the second most common type of mammalian bite after dog bites, but the wounds following a cat's bite are nearly twice as likely to become infected as wounds from dog bites.5
Clinical Approach (Pathogenesis and Treatment)
The evaluation and treatment of all bite wounds should include taking a careful history of the incident, the type of animal, the site of the bite, and the geographic setting. Hand wounds, puncture wounds, and crush injuries are likely to become infected. Specimens from infected bites should be cultured and a Gram-stained smear prepared; the wound should then be washed, well-irrigated, and left open. Most patients with bites on the hands, deep cat bites, deep cat scratches, and sutured wounds should be treated with amoxicillin/clavulanic acid or ceftriaxone because of the risk of Pasteurella multocida infection; if the patient is allergic to these agents a quinolone or a tetracycline should be used. Evidence that the use of prophylactic antibiotics ...