2006 Annual Report 4d.Progress report. This report serves to document research conducted under a reimbursable agreement between ARS and the Department of Homeland Security. Additional details of research can be found in the report for the parent CRIS (6612-32000-041-00X). H5N1 HPAI virus could be transmitted to chickens during a simulated live poultry market slaughter. H5N1 high pathogenicity avian influenza (HPAI) virus has caused poultry outbreaks on 3 continents. Transmission between birds is poorly understood. In this study, we conducted simulated live poultry market slaughter of H5N1 infected chickens. Moderate levels of virus were recovered from the room air and chickens placed within 2, 5 and 10 feet of the processing became infected and died. This data indicates that H5N1 HPAI virus is aerosolized during slaughter of infected poultry and can serve as a method of transmission within the live poultry markets.