Rabies is transmitted only when the virus is introduced into abite wound open cuts in skin , or mucous membranes ( such as the mouth or eyes).
When an exposure has occurred , the likehood of rabies infection varies with the nature and extent of exposure . Under most circumstances , two categories of exposure –bite and nonbite – should be considered.
Any penetration of the skin by teeth constutes a bite exposure . All bites , regardless of body site , represent a potential risk of rabies transmission , but that risk varies with the species of biting animal , the anatomic site of the bite , and the severity of the wound.
Bites by some animals , such as bats , can inflict minor injury and thus be difficult to detect.
Nonbite exposures from terrestrial animals raely cause rabies . However , occasional reports of rabies transmission by nonbite exposures suggest that such exposures should be evaluated for possible PEP administration .
The contamination of open wounds , abrasions mucous membranes , or theoretically , scratches ( potentially contaminated with infectious material from a rabid animal ) also constitutes anonbite exposure.
Other contact by itself such as petting arbid animal and contact with blood , urine , or feces of rabid animal , does not constitute an exposure and is not an indication for PEP.
An unprovoked attack by an animal is more likely than aprovoked attack to indicate that the animal is rabid . Bites inflicted on aperson attempting to feed or handle an apparently healthy animal should generally be regarded as provoked .
Other factors to consider when evaluating a potential rabies exposure include the local rabies epidemiology in the area , the biting animal’s history and current health status ( e.g . abnormal behavior ,signs of illness ) , and the potential for the animal to be exposed to rabies ( e.g. , presence of an unexplained wound or history of exposure to a rabid animal) .