What is the risk of rabies transmission from a cat scratch?

Risk of Rabies Transmission from Cat Scratches

Nonbite exposures such as cat scratches very rarely cause rabies, but transmission is possible if saliva or other potentially infectious material from a rabid cat contaminates open wounds or abrasions. 1

Transmission Risk Assessment

• Cat scratches alone do not constitute a rabies exposure unless they are contaminated with saliva or other potentially infectious material (e.g., neural tissue) from a rabid animal 1
• For rabies transmission to occur, the virus must be introduced into fresh, open cuts in skin or onto mucous membranes 1
• The contamination of scratches with saliva from a rabid animal constitutes a nonbite exposure that requires assessment for potential post-exposure prophylaxis 1
• Rabies virus is inactivated by desiccation, ultraviolet irradiation, and other factors and does not persist in the environment - if the suspect material is dry, the virus can be considered noninfectious 1

Risk Factors That Increase Concern

• Scratches from cats with abnormal behavior, neurological signs, or unexplained aggressive behavior should be considered high-risk 2
• Two clinical manifestations of rabies have been identified in cats: the furious form and the dumb form, with death occurring after a clinical course of 1-10 days 2
• The average incubation period for rabies in cats is 2 months but may vary from 2 weeks to several months or even years 2
• There are documented cases of paralytic rabies following cat scratch where post-exposure prophylaxis failed (particularly when rabies immunoglobulin was not administered) 3

Management of Cat Scratches

• Immediate and thorough washing of all scratches with soap and water for about 15 minutes is the most effective measure for preventing rabies transmission 4, 5

• The decision to initiate rabies post-exposure prophylaxis depends on:

  1. The nature of the exposure (whether saliva contaminated the scratch) 1
  2. The epidemiology of rabies in the area where the exposure occurred 1
  3. The species and vaccination status of the animal involved 1
  4. The availability of the animal for observation or testing 1

• If the cat appears healthy and is available for observation, it should be confined and observed for 10 days 1

• If the cat remains alive and healthy 10 days after the incident, it would not have been shedding rabies virus in its saliva at the time of the scratch 1

Other Health Concerns from Cat Scratches

• Cat scratches can also lead to bacterial infections, most commonly cat-scratch disease caused by Bartonella henselae 5, 6
• Cat-scratch disease typically presents as self-limiting lymphadenopathy and affects an estimated 22,000 people in the United States each year 6, 7
• Antibiotic treatment with amoxicillin-clavulanate is recommended for prophylaxis against bacterial infection in cat scratch wounds 8, 5

When to Seek Post-Exposure Prophylaxis

• Consult with local or state public health officials to determine the need for rabies post-exposure prophylaxis following a cat scratch 1

• Post-exposure prophylaxis should be considered if:

  1. The scratch was contaminated with saliva from a rabid or potentially rabid cat 1, 4
  2. The cat exhibited abnormal behavior suggestive of rabies 2
  3. The cat is unavailable for observation or testing and rabies is endemic in the area 1

• If post-exposure prophylaxis is indicated, both rabies immune globulin and rabies vaccine should be administered as soon as possible 4

• Failure to administer rabies immune globulin along with the vaccine can result in treatment failure, as documented in case reports 3