Factors Associated with Highly Pathogenic Avian Influenza H5N2 Infection on Table-Egg Layer Farms in the Midwestern United States, 2015.
A case-control study was conducted among commercial table-egg layer and pullet operations in Iowa and Nebraska, United States, to investigate potential risk factors for infection with highly pathogenic avian influenza (HPAI) H5N2. A questionnaire was developed and administered to 28 case farms and 31 control farms. Data were collected at the farm and barn levels, enabling two separate analyses to be performed-the first a farm-level comparison of case farms vs. control farms, and the second a barn-level comparison between case barns on case farms and control barns on control farms. Multivariable logistic regression models were fit using a forward-selection procedure. Key risk factors identified were farm location in an existing control zone, rendering and garbage trucks coming near barns, dead-bird disposal located near barns, and visits by a company service person. Variables associated with a decreased risk of infection included visitors changing clothing, cleaning and disinfecting a hard-surface barn entryway, and ceiling/eaves ventilation in barns.
A United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Science Technology and Analysis Services, Center for Epidemiology and Animal Health, 2150 Centre Avenue, Building B, Fort Collins, CO 80526.
Lindsey
L
Garber
A United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Science Technology and Analysis Services, Center for Epidemiology and Animal Health, 2150 Centre Avenue, Building B, Fort Collins, CO 80526.
Kathe
K
Bjork
A United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Science Technology and Analysis Services, Center for Epidemiology and Animal Health, 2150 Centre Avenue, Building B, Fort Collins, CO 80526.
Kelly
K
Patyk
B Incursion Investigation and Surveillance Team, Investigation Diagnostic Centres and Response Directorate, Ministry for Primary Industries, 66 Ward Street, Wallaceville, Upper Hutt 5040, New Zealand.
Thomas
T
Rawdon
A United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Science Technology and Analysis Services, Center for Epidemiology and Animal Health, 2150 Centre Avenue, Building B, Fort Collins, CO 80526.
Maria
M
Antognoli
A United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Science Technology and Analysis Services, Center for Epidemiology and Animal Health, 2150 Centre Avenue, Building B, Fort Collins, CO 80526.
Amy
A
Delgado
A United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Science Technology and Analysis Services, Center for Epidemiology and Animal Health, 2150 Centre Avenue, Building B, Fort Collins, CO 80526.
Sara
S
Ahola
A United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Science Technology and Analysis Services, Center for Epidemiology and Animal Health, 2150 Centre Avenue, Building B, Fort Collins, CO 80526.
Brian
B
McCluskey
D000818:Animals; D016022:Case-Control Studies; D002645:Chickens; D000072480:Farms; D005260:Female; D053125:Influenza A Virus, H5N2 Subtype / Q000502:physiology*; D005585:Influenza in Birds / Q000453:epidemiology* / Q000635:transmission* / Q000821:virology; D007484:Iowa / Q000453:epidemiology; D009329:Nebraska / Q000453:epidemiology; D011201:Poultry Diseases / Q000453:epidemiology* / Q000635:transmission* / Q000821:virology
H5N2; avian influenza; highly pathogenic; risk factors; table-egg layers