Social network analysis of the movement of poultry to and from live bird markets in Bali and Lombok, Indonesia.
Highly pathogenic avian influenza H5N1 has resulted in large losses to the Indonesian poultry sector. Evidence suggests that live bird markets (LBMs) play an important role in the epidemiology of the disease. Knowledge of the frequency and type of contact between the various poultry market players should allow animal health authorities to develop a better understanding of factors influencing virus transmission between Indonesian villages. A questionnaire-based cross-sectional survey was conducted in 17 LBMs on the neighbouring Indonesian islands of Bali and Lombok to investigate the movement patterns of poultry to and from markets. Using social network analyses, a network of contacts was created for each island from a total of 413 live poultry traders and 134 customers. Individual nodes with high degree and/or betweenness were identified in each network. The Lombok network was more dense and connected than the Bali network indicating that disease transmission would be more efficient in the Lombok network. Our findings indicate that whilst live poultry are typically transported over relatively short distances of approximately 10 km, it is not uncommon for traders and customers to travel in excess of 100 km to buy or sell poultry, which may facilitate the spread of disease over a large geographical area. This study highlights the different roles markets play in poultry movement networks and their potential for disease dissemination. The identification of highly influential market nodes allows authorities to target HPAI surveillance activities to locations where disease is more likely to be present, which is crucial in low-resource settings.
School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia.|Department of Global Health, Research School of Population Health, Australian National University, Acton, ACT, Australia.
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http://orcid.org/0000-0002-6858-7501
J
Kurscheid
Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville, Vic., Australia.
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M
Stevenson
Australian Animal Health Laboratory, Commonwealth Science and Industry Organisation, Geelong, Vic., Australia.
P A
http://orcid.org/0000-0003-0851-5300
PA
Durr
Faculty of Veterinary Science, Camden Campus, School of Life and Environmental Sciences, The University of Sydney, Camden, NSW, Australia.
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JLML
Toribio
John Curtin School of Medical Research, Australian National University, Acton, ACT, Australia.
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S
Kurscheid
Agribusiness Study Program, Faculty of Agriculture, Udayana University, Denpasar, Bali, Indonesia.
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IGAA
Ambarawati
Research Center for Rural Development, Mataram University, Mataram, Lombok, Indonesia.
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M
Abdurrahman
Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, Boston, MA, USA.
S
S
Fenwick
D000818:Animals; D003132:Commerce; D003430:Cross-Sectional Studies; D006801:Humans; D007214:Indonesia / Q000453:epidemiology; D053124:Influenza A Virus, H5N1 Subtype / Q000472:pathogenicity / Q000502:physiology*; D005585:Influenza in Birds / Q000453:epidemiology* / Q000635:transmission / Q000821:virology; D011200:Poultry; D011201:Poultry Diseases / Q000453:epidemiology* / Q000635:transmission / Q000821:virology; D011795:Surveys and Questionnaires
H5N1; Indonesia; highly pathogenic avian influenza; live bird markets; social network analysis