Wind-Borne Transmission of Infectious Laryngotracheitis Between Commercial Poultry Operations


Authors

  • Y.J. Johnson American Academy for the Advancement of Science, Global Security Fellow Office of Science and Technology Policy, Executive Office of the President, Washington, DC 20502, USA
  • N. Gedamu American Academy for the Advancement of Science, Global Security Fellow Office of Science and Technology Policy, Executive Office of the President, Washington, DC 20502, USA
  • M.M. Colby American Academy for the Advancement of Science, Global Security Fellow Office of Science and Technology Policy, Executive Office of the President, Washington, DC 20502, USA
  • M.S. Myint American Academy for the Advancement of Science, Global Security Fellow Office of Science and Technology Policy, Executive Office of the President, Washington, DC 20502, USA
  • S.E. Steele American Academy for the Advancement of Science, Global Security Fellow Office of Science and Technology Policy, Executive Office of the President, Washington, DC 20502, USA
  • M. Salem American Academy for the Advancement of Science, Global Security Fellow Office of Science and Technology Policy, Executive Office of the President, Washington, DC 20502, USA
  • N.L Tablante American Academy for the Advancement of Science, Global Security Fellow Office of Science and Technology Policy, Executive Office of the President, Washington, DC 20502, USA

DOI:

https://doi.org/10.3923/ijps.2005.263.267

Keywords:

Epidemiology, geographic information systems, Infectious laryngotracheitis, windborne

Abstract

Infectious Laryngotracheitis (ILT) is an acute respiratory disease of poultry and causes significant economic losses due to increased mortality and decreased productivity. First described in 1925, ILT has been extensively studied, but little is known about the epidemiology of the disease. In the past 15 years, there have been severe ILT outbreaks in several poultry-producing states. The spread of ILT in outbreak situations is typically quite rapid, and then in an ever-widening arc around the initial case. The mechanism of this spread is not well understood, and many hypotheses are currently in existence. Several risk factors that have been identified are indicative of wind-borne transmission. A case-control study of 18 case and 122 control flocks was conducted. A GIS database of poultry operations and meteorological data from local weather stations were employed to analyze the risk of clinical ILT associated with prevailing wind patterns. Case farms were 9.9 times more likely located within the wind vector of a clinical ILT flock during the 14 day incubation period for ILT than control flocks (p< 0.001). House orientation and proximity to a backyard flock or a commercial flock were not significantly associated with case status. The control-to-case flock distance was significantly greater than the case-to-case flock distance (p=0.03). House ventilation system, wind vector, and distance from another case flock were presented to a backward eliminating logistic regression model. Only wind vector variable was retained in the model. The point estimate for the odds ratio was 0.110 (95% confidence interval 0.038 - 0.322).

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Published

2005-04-15

Issue

Vol. 4 No. 5 (2005)

Section

Research Article

License

Copyright (c) 2005 Asian Network for Scientific Information

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.

How to Cite

Johnson, Y., Gedamu, N., Colby, M., Myint, M., Steele, S., Salem, M., & Tablante, N. (2005). Wind-Borne Transmission of Infectious Laryngotracheitis Between Commercial Poultry Operations. International Journal of Poultry Science, 4(5), 263–267. https://doi.org/10.3923/ijps.2005.263.267