Using quantitative disease dynamics as a tool for guiding response to avian influenza in poultry in the United States of America

Authors: PEPIN, KIM - Colorado State University; Spackman, Erica; BROWN, JUSTIN - University Of Georgia; PABILONIA, KRIST - Colorado State University; GARBER, LINDSEY - Animal And Plant Health Inspection Service (APHIS); WEAVER, TODD - Animal And Plant Health Inspection Service (APHIS); KENNEDY, DAVE - Pennsylvania State University; PATYK, KELLY - Animal And Plant Health Inspection Service (APHIS); HUYVAERT, KATE - Colorado State University; MILLER, RYAN - Animal And Plant Health Inspection Service (APHIS); FRANKLIN, ALAN - Animal And Plant Health Inspection Service (APHIS); PEDERSEN, KERRI - Animal And Plant Health Inspection Service (APHIS); BOGICH, TIFFANY - Princeton University; ROHANI, PEJMAN - Michigan State University; SHRINER, SUSAN - Animal And Plant Health Inspection Service (APHIS); WEBB, COLLEEN - Colorado State University; RILEY, STEVEN - Imperial College

Submitted to: Preventive Veterinary Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/25/2013
Publication Date: 3/1/2014
Publication URL: http://handle.nal.usda.gov/10113/60127
Citation: Pepin, K., Spackman, E., Brown, J., Pabilonia, K., Garber, L., Weaver, T., Kennedy, D., Patyk, K., Huyvaert, K., Miller, R., Franklin, A., Pedersen, K., Bogich, T., Rohani, P., Shriner, S., Webb, C., Riley, S. 2014. Using quantitative disease dynamics as a tool for guiding response to avian influenza in poultry in the United States of America. Preventive Veterinary Medicine. 113(4):376-397. DOI: 10.1016/j.prevetmed.2013.11.011.

Interpretive Summary: Computer models are a valuable tool for elucidating how diseases spread, which can inform the development of control plans. Developing models for specific aspects of avian influenza spread, for example the interface between wild birds and poultry, will aid our ability to control and even prevent the disease. Here we focus on the history of avian influenza virus in the United States and the structure of the poultry industry in the united states to identify gaps in data necessary to build the models and compiling relevant data for model construction. We determine that current data can be used to develop critical models for virus spread from wild birds to domestic birds, virus spread between and among farms during an outbreak, and how virus spread may differ among differ parts of the poultry industry.

Technical Abstract: Wild birds are the primary source of genetic diversity for influenza A viruses that eventually emerge in poultry and humans. Much progress has been made in the descriptive ecology of avian influenza viruses (AIVs), but contributions from quantitative studies are less evident. Transmission between hosts species, host individuals or flocks has not been quantified with sufficient accuracy to allow robust quantitative evaluation of alternate control protocols. We focused on the United States of America (USA) as a case study for determining the state of our quantitative knowledge of AIV emergence processes from wild hosts to poultry. We identified priorities for quantitative research that would build on existing tools for responding to AIV in poultry. We concluded that the following knowledge gaps can be addressed with current empirical data: 1) quantify the spatio-temporal relationship between AIV prevalence in wild hosts and poultry populations, 2) understand how the structure of different poultry sectors impacts within-flock transmission, and 3) determine mechanisms and rates of between-farm spread, and 4) validate current policy-decision tools with data. The modeling studies we recommend will improve our mechanistic understanding of potential AIV transmission patterns in USA poultry, leading to improved measures of accuracy and uncertainty when evaluating alternative control strategies.