Poultry farmer response to disease outbreaks in smallholder farming systems in southern Vietnam

  1. Alexis Delabouglise  Is a corresponding author
  2. Nguyen Thi Le Thanh
  3. Huynh Thi Ai Xuyen
  4. Benjamin Nguyen-Van-Yen
  5. Phung Ngoc Tuyet
  6. Ha Minh Lam
  7. Maciej F Boni
  1. CIRAD, France
  2. Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Viet Nam
  3. Ca Mau sub-Department of Livestock Production and Animal Health, Viet Nam
  4. Ecole Normale Superieure, France
  5. Pennsylvania State University, United States

Abstract

Avian influenza outbreaks have been occurring on smallholder poultry farms in Asia for two decades. Farmer responses to these outbreaks can slow down or accelerate virus transmission. We used a longitudinal survey of 53 small-scale chicken farms in southern Vietnam to investigate the impact of outbreaks with disease-induced mortality on harvest rate, vaccination, and disinfection behaviors. We found that in small broiler flocks (≤16 birds/flock) the estimated probability of harvest was 56% higher when an outbreak occurred, and 214% higher if an outbreak with sudden deaths occurred in the same month. Vaccination and disinfection were strongly and positively correlated with the number of birds. Small-scale farmers – the overwhelming majority of poultry producers in low-income countries – tend to rely on rapid sale of birds to mitigate losses from diseases. As depopulated birds are sent to markets or trading networks, this reactive behavior has the potential to enhance onward transmission.

Data availability

The study dataset is available online at the Open Science Framework, https://osf.io/ws3vu/.

The following data sets were generated

Article and author information

Author details

  1. Alexis Delabouglise

    ASTRE, CIRAD, Montpellier, France
    For correspondence
    alexis.delabouglise@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5837-7052
  2. Nguyen Thi Le Thanh

    Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
    Competing interests
    The authors declare that no competing interests exist.
  3. Huynh Thi Ai Xuyen

    Ca Mau sub-Department of Livestock Production and Animal Health, Ca Mau, Viet Nam
    Competing interests
    The authors declare that no competing interests exist.
  4. Benjamin Nguyen-Van-Yen

    CNRS UMR 8197, Ecole Normale Superieure, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  5. Phung Ngoc Tuyet

    Ca Mau sub-Department of Livestock Production and Animal Health, Ca Mau, Viet Nam
    Competing interests
    The authors declare that no competing interests exist.
  6. Ha Minh Lam

    Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
    Competing interests
    The authors declare that no competing interests exist.
  7. Maciej F Boni

    Center for Infectious Diseases Dynamics, Pennsylvania State University, University Park, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0830-9630

Funding

Wellcome (098511/Z/12/Z)

  • Maciej F Boni

Defense Threat Reduction Agency

  • Maciej F Boni

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Human subjects: The research collaboration was approved by the Hospital for Tropical Diseases in Ho Chi Minh City, and the study design was approved by the Ca Mau sub-Department of Livestock Production and Animal Health. The Ca Mau sub-Department of Livestock Production and Animal Health (CM-LPAH) specifically approved this study and is equivalent to an Animal Care and Use Committee that approves studies like this in Vietnam. CM-LPAH approved the publication of these results. No consenting process was required as the study involved no human biological samples, no patients, and no personal or identifiable information. The IRB that made this determination was the Hospital for Tropical Diseases Scientific and Ethical Committee (Ho Chi Minh City).

Reviewing Editor

  1. Joshua T Schiffer, Fred Hutchinson Cancer Research Center, United States

Publication history

  1. Received: May 22, 2020
  2. Accepted: August 21, 2020
  3. Accepted Manuscript published: August 25, 2020 (version 1)
  4. Version of Record published: September 21, 2020 (version 2)

Copyright

© 2020, Delabouglise et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Alexis Delabouglise
  2. Nguyen Thi Le Thanh
  3. Huynh Thi Ai Xuyen
  4. Benjamin Nguyen-Van-Yen
  5. Phung Ngoc Tuyet
  6. Ha Minh Lam
  7. Maciej F Boni
(2020)
Poultry farmer response to disease outbreaks in smallholder farming systems in southern Vietnam
eLife 9:e59212.
https://doi.org/10.7554/eLife.59212

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