2008 Annual Report 1a.Objectives (from AD-416) The objective of this cooperative research project is to study the biological characteristics of low pathogenic Avian Influenza (LPAI) isolates by experimental infection of common domestic avian species (chickens, turkeys, and ducks). This information will be compared to the sequence of the virus to try and understand how the genotype affects the phenotype. Additional studies to evaluate potential routes of transmission of avian influenza virus on the farm will be performed. This information will be used to improve current stochastic models of avian influenza spread on farms. 1b.Approach (from AD-416) Pathogenicity and transmissibility studies planned following a standard protocol will be conducted to evaluate the biological characteristics of low pathogenic Avian Influenza (LPAI) virus isolates in different domestic birds. Experiments will be conducted at the Poultry Diagnostic and Research Center (PDRC) at the University of Georgia with LPAI viruses selected from the Southeast Poultry Research Laboratory (SEPRL) repository. The transmission studies will include field work on farms to evaluate contact and spread of virus on and between farms. A combination of surveys and investigator studies of people and equipment movement on farms will be conducted. 3.Progress Report Progress related to Objective 3 of the in-house project: Conduct genomic sequencing of avian influenza (AI) viruses and determining the biological and molecular epidemiological relevance of genetic information. This project focused on pathobiological impact of wild-bird avian influenza (AI) viruses on domestic poultry and the epidemiology of on-farm transmission. During 2008, 16 wild bird origin H4, H6 and H9 low pathogenicity avian influenza (LPAI) viruses were inoculated into 4-week old specific pathogen free (SPF) chickens and 3-week old commercial turkeys. Virus replication was detected by real time reverse transcription-polymerase chain reaction (RT-PCR) for 11 of 16 viruses given to chickens and 8 out of 16 viruses given to turkeys. No clinical signs were observed except for one virus that caused mild upper-respiratory signs in turkeys and resulted in one death and one moribund bird. Histopathological lesions, consistent with viral infection, were observed in chickens and were confined to the upper-respiratory and gastrointestinal tracts. Seroconversion was detected by enzyme-linked immuno sorbant assay (ELISA) and hemagglutination-inhibition (HI) tests in chickens for 4 of 16 viruses and in turkeys for 13 of 16 viruses. In an effort to evaluate poultry producer compliance with recommended biosecurity procedures for disease prevention and control, participating companies were contacted and asked for any materials that they provide to their contract growers. Most companies did not provide specific materials or requirements to contract growers pertaining to biosecurity. A poultry grower survey was distributed to 1035 to poultry growers with 171 growers representing 5 different companies returned completed surveys. The data is currently being evaluated. A stochastic model was evaluated to examine the sensitivity of the model to input data: Infectious period - the effect of varying the infectious period of the virus from 3 days to 6 days; Transmission rate - effect of varying the transmission rate between 10 contacts/infected bird up to 140 contacts/infected bird. Varying the infectious period had minimal impact on varying the transmission rate. While varying the transmission rate resulted in accelerating the outbreak dynamics, the actual times to potential off-farm spread of virus (based upon birds in infectious class) did not change by more than 1 day except at the extremes of the range. The dynamics of the outbreak on the farm, combined with the reported poultry grower sensitivity to morbidity and mortality, resulted in poultry grower detection of the outbreak between days 4 and 8, depending upon bird age at the onset of disease, under all evaluated conditions. MONITORING: The Authorized Departmental Officer's Designated Representative (ADODR) had regular email and telephone conversations with the cooperator at the University of Georgia on research progress. There has been one face-to-face meeting in Athens, Georgia.