Composting for avian influenza virus elimination

Area of Science:

• Veterinary Virology
• Environmental Microbiology
• Biosecurity

Background:

• Viral epizootic outbreaks necessitate effective pathogen sanitization methods.
• Manure management is critical for preventing the spread of avian influenza virus (AIV).
• Thermal inactivation is a potential strategy for decontaminating infectious materials.

Purpose of the Study:

• To evaluate thermal inactivation of highly pathogenic avian influenza virus (H7N1) in inoculated manure.
• To assess the efficacy of bacteriophages MS2 and 6 as indicator organisms for AIV during thermal treatment.
• To inform guidelines for emergency composting of contaminated litter.

Main Methods:

• Inoculation of manure with H7N1, MS2, and bacteriophage 6.
• Exposure of inoculated manure to various temperatures (35°C, 45°C, 55°C).
• Quantification of viral and bacteriophage inactivation rates.

Main Results:

• Rapid inactivation of H7N1 was observed at mesophilic and thermophilic temperatures.
• Bacteriophage 6 showed similar inactivation rates to H7N1.
• Bacteriophage MS2 exhibited high thermoresistance, making it unsuitable as an indicator for AIV thermal inactivation.

Conclusions:

• Thermal treatment is effective for sanitizing H7N1 in manure.
• Bacteriophage 6 can serve as a reliable indicator organism for AIV thermal inactivation.
• Bacteriophage MS2 is not recommended for monitoring thermal decontamination of AIV.
• Study findings support developing guidelines for emergency composting of contaminated poultry litter.