2005 - Animal Bites

Animal bites to humans are reportable in order to assess the transmission risk of rabies virus from animals to humans and to assess the need for rabies postexposure prophylaxis. This risk assessment can be accomplished by several methods. The most frequently used method is observation of the offending animals for 10 days (dogs, cats, and ferrets). When observing the animal is not appropriate, laboratory testing of the animal’s brain serves as an alternative assessment method.

While the incidence of rabies disease in Indiana’s domestic animals is low, animal bites are still a public health issue as they are a preventable injury that causes pain, trauma and infection, loss of function, disfigurement, and anxiety.

Animal bites are suffered disproportionately by the young. In 2005, 49 percent of reported bites in Indiana occurred to individuals less than 20 years of age. Figure 1 shows the number of animal bite victims by age and sex. The rate of bite injury in children less than 1 year of age (684.18) is over two times that of any other age group. In children less than 1 year of age, 80 percent of animal bites were from dogs, 15 percent were from cats, and 1 percent was from bats.

Most animal bites are associated with animals that have the greatest interaction with humans. Of the 7,857 animal bites analyzed, 6,193 (79%) were committed by dogs and 1,377 (18%) by cats. A number of other wild and domestic species committed the remaining 3 percent. Table 1 presents the number of reported bites by species. The category “other” includes bites by guinea pigs, muskrats, a coyote, and a monkey.

Rabies vaccination status was reported for 49 percent of biting dogs and 32 percent of biting cats. Of those animals with a reported vaccination status, 72 percent of dogs and 54 percent of cats were vaccinated for rabies (Figure 2). The difference in vaccination percentages is possibly due to dogs being associated with rabies and Indiana law requiring dogs to be vaccinated. Nationally, cats are diagnosed with rabies more frequently than dogs, especially in states where the raccoon rabies variant is present.

Two steps have been suggested to reduce animal bites: confinement and neutering. The 2005 Indiana animal bite data do not support this suggestion. For both dogs and cats, more bites were reported from confined animals than unconfined (Figure 3), and only intact male dogs were involved in more bites than other neutered animals (Figure 4 and Figure 5). Widespread community “leash laws” may be a factor in fewer reported animal bites by unconfined animals. According to the Centers for Disease Control and Prevention (CDC), most dog bites incurred by persons 18 years of age or younger are by either a family or neighbor’s dog.

You can learn more about animal bites by visiting the following Web sites: http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5226a1.htm