Bird Flu (Avian Influenza) Transmission to Humans: Routes and Prevention

Avian influenza (bird flu) is caused by influenza A viruses (e.g., H5N1, H7N9) that primarily infect birds. Human infections are rare but can be severe.

Transmission Routes

1. Direct Contact: Handling infected live/dead birds, feathers, feces, respiratory secretions. Highest risk: poultry workers, cullers, live-market vendors.
2. Environmental/ Fomite: Virus survives days in feces, water, feathers, surfaces. Touching contaminated objects then mucosa (eyes, nose, mouth).
3. Aerosol/Inhalation: Inhaling dust/droplets from infected flocks, especially in enclosed spaces.
4. Foodborne: Not a route for properly cooked poultry/eggs. Virus destroyed at 70°C (165°F).

Human-to-Human Spread

Extremely rare; limited, non-sustained clusters in close contacts. No sustained community transmission documented.

Prevention

• Avoid contact with sick/dead birds; report to authorities.
• Use PPE (gloves, masks, goggles) when handling poultry.
• Wash hands thoroughly with soap after bird contact.
• Cook poultry/eggs thoroughly.
• Seasonal flu vaccine reduces co-infection risk (reassortment).
• Antivirals (oseltamivir) for post-exposure prophylaxis in high-risk contacts.