HPAI spread by poor biosecurity

The USDA’s Animal and Plant Health Inspection Service (APHIS) recently released an updated epidemiology report outlining its findings on the spread of the highly pathogenic AI through June 5.

Through the use of genetic analyses of the HPAI virus, APHIS scientists found identical viruses in farm clusters indicating transmission by employees and equipment. The analyses also pointed to independent introductions occurring in several states concurrently.

In addition, virus particles were found in air samples collected outside infected poultry houses. Initial studies of wind data in these areas showed a relationship between sustained high winds and an increase in the number of infected farms approximately 5 days later.

APHIS analysis of more than 80 commercial poultry farms indicates several routes of possible virus transmission including:

• Wild birds
• Employees moving between infected and noninfected farms
• Equipment moving between infected and noninfected farms
• Vehicles moving between infected and noninfected farms without cleaning or disinfection
• Rodents or small birds inside poultry houses
• Environmental factors include airborne virus distribution

Full report (PDF)