Can cats carry Pasteurella on their claws?

Pasteurella on Cat Claws: Transmission Risk and Prevention

Yes, cats can carry Pasteurella on their claws, making scratches a significant transmission route for this bacterial infection. 1 Pasteurella species are part of the normal oral flora of cats, and can contaminate their claws during grooming or when they retract their claws through their oral cavity.

Transmission of Pasteurella from Cats to Humans

• Primary transmission routes:

  • Cat scratches (30-50% infection rate, significantly higher than dog bites at 5-25%) 2
  • Cat bites
  • Contact with respiratory secretions 1

• Infection characteristics:

  • Signs of local infection after a cat scratch typically appear within 3-6 hours 1
  • Infections manifest as rapidly developing cellulitis at the site of injury 3
  • Wounds typically produce serosanguineous or purulent drainage 3

Risk Factors for Severe Infection

• Location of scratch: Hands, feet, areas near joints, face, and genitals have higher infection risk 2
• Timing of treatment: Wounds treated more than 24 hours after injury have increased infection risk 2
• Wound depth: Deep wounds have higher infection rates 2
• Immune status: Immunocompromised individuals, especially those with HIV and low CD4+ counts, are at high risk for severe infections 2

Prevention Recommendations

According to guidelines for preventing opportunistic infections in HIV-infected persons (which provide comprehensive recommendations for cat-related infections):

1. For immunocompromised individuals:

   • Consider the risks of cat ownership carefully 4
   • If acquiring a cat, choose one over 1 year of age in good health 4

2. For all cat owners:

   • Avoid rough play with cats and situations where scratches are likely 4
   • Wash any cat-associated wound promptly with soap and water 4
   • Do not allow cats to lick open wounds or cuts 4
   • Implement proper flea control for cats 4

3. Although declawing is not generally advised, keeping cats' nails trimmed can help reduce scratch risk 2

Management of Cat Scratches

• Immediate wound care:

  • Deep irrigation of the wound to remove foreign bodies and pathogens 2
  • Remove any necrotic tissue to reduce pathogen burden 2

• Antibiotic treatment:

  • Penicillin or its derivatives are the preferred treatment for Pasteurella infections 5, 3
  • For cat scratch disease caused by Bartonella henselae:
    • Azithromycin is first-line (500 mg on day 1, then 250 mg for 4 days) 2
    • Alternative treatments include erythromycin or doxycycline 2

Special Considerations

• Monitoring: Schedule follow-up within 24-48 hours for scratches showing signs of infection 2
• Complications: Without proper treatment, Pasteurella infections can lead to abscess formation, tenosynovitis, septic arthritis, and osteomyelitis 6
• Severe outcomes: While severe disease and fatal outcomes are more common in immunocompromised individuals, they have also been reported in healthy people 1

Remember that the acute onset of cellulitis, lymphangitis, and serosanguineous or purulent drainage from wounds 12-24 hours after cat scratches strongly suggests Pasteurella multocida as the predominant pathogen 3.