Disinfection Best Practices in Animal Facilities
Effective disinfection is critical for maintaining pathogen-free vivarium environments. Key principles:
Contact time matters: The single most common error in vivarium disinfection is wiping surfaces before the required contact time has elapsed. A 10-minute contact time means the surface must remain wet with disinfectant for the full 10 minutes.
Cleaning before disinfecting: Organic matter (bedding, food, feces) inactivates most disinfectants. Always clean surfaces of visible debris before applying disinfectant. The standard workflow is: remove gross debris → clean with detergent → rinse → apply disinfectant → wait contact time → rinse if required.
Rotation and resistance: Some facilities rotate between disinfectant classes (oxidizing, quaternary ammonium, phenolic) to prevent resistance. While bacterial resistance to disinfectants is less clinically significant than antibiotic resistance, biofilm formation can reduce efficacy over time.
Common disinfectant classes in vivaria:
- Chlorine dioxide (Clidox-S): Fast-acting, broad-spectrum, relatively safe
- Quaternary ammonium (MB-10): Economical, low toxicity, good surface compatibility
- Peroxygen (Virkon-S): Excellent virucidal activity, pink color indicates potency
- Sodium hypochlorite (bleach): Inexpensive, effective, but corrosive and unstable
- Alcohol + quaternary ammonium (CaviCide): Ready-to-use convenience for procedure areas