A 32-year-old nurse in a tertiary care hospital in Mumbai sustained a needlestick injury from a patient with unknown HIV and hepatitis B status. The contaminated needle and syringe require immediate disinfection before disposal. Which agent is the drug of choice for rapid surface disinfection of blood-contaminated sharps in this occupational exposure scenario?

Explanation

## Disinfection of Blood-Contaminated Sharps in Occupational Exposure **Key Point:** Sodium hypochlorite (bleach) 0.5% is the preferred disinfectant for immediate decontamination of blood-contaminated sharps and surfaces in occupational exposure incidents, particularly for bloodborne pathogens (HIV, HBV, HCV). ### Why Sodium Hypochlorite is Superior **High-Yield:** Sodium hypochlorite is: 1. **Rapid-acting**: Kills bloodborne viruses within seconds to minutes 2. **Virucidal**: Highly effective against enveloped viruses (HIV, HBV) and non-enveloped viruses 3. **Cost-effective**: Inexpensive and readily available in all healthcare settings 4. **Penetrating**: Effective even in the presence of organic matter (blood, body fluids) ### Mechanism of Action Hypochlorite releases hypochlorous acid (HOCl), which oxidizes and denatures viral proteins and nucleic acids, achieving rapid inactivation of bloodborne pathogens. ### Disinfectant Comparison for Sharps Contamination | Agent | Contact Time | Virucidal (HIV/HBV) | Organic Matter Tolerance | Practical Use | |---|---|---|---|---| | **Sodium hypochlorite 0.5%** | **30 sec–2 min** | **Excellent** | **Good** | **Immediate surface/sharp disinfection** | | Glutaraldehyde 2% | 20–30 min (HLD) | Excellent | Excellent | Prolonged soak; not practical for immediate sharps | | Ethanol 95% + acetic acid | 1–5 min | Good | Poor (inactivated by blood) | Limited use in presence of organic matter | | Quaternary ammonium compounds | 5–10 min | Moderate | Poor (inactivated by blood) | Not recommended for bloodborne pathogen exposure | **Clinical Pearl:** The CDC and WHO recommend 0.5% sodium hypochlorite for immediate disinfection of surfaces and sharps contaminated with blood or body fluids in occupational exposure settings. A 1:10 dilution of household bleach (5% stock) yields 0.5% working solution. **Warning:** Glutaraldehyde, while sporicidal, requires 20–30 minutes for high-level disinfection and is impractical for immediate sharps decontamination in occupational exposure. Ethanol and quaternary ammonium compounds are inactivated by blood proteins, reducing efficacy.