Flock Size and HPAI Risk in Cambodia,
Thailand, and Viet Nam.
Open / Free access
Otte, J.; Pfeiffer, D.; Soares-Magalhaes, R.; Burgos, S.; Roland-Holst, D.
HPAI Research Brief No. 5, 2008. 4 pp.
Cambodia, Thailand, Viet Nam
Because the majority of HPAI outbreaks in Asia have been reported in smallholder 'backyard'
flocks, there is an assumption these small flocks, with typical flock sizes of well under 50
birds, largely, but not exclusively kept for home consumption, have an inherently higher risk
of contracting and thereby disseminating HPAI than larger market-oriented flocks
maintained in poultry operations following the specialized, high-input production models of
industrialized countries. This assumption was tested using HPAI reports from Cambodia,
published data from the first 2004 HPAI epidemic and concurrent active surveillance
programme in Thailand, and data collected in Viet Nam by the national animal health
authorities during the second, third and fourth epidemic waves. In fact, the highest HPAI risk
appeared to be associated with those producers best able to finance improved risk reduction
measures themselves, i.e. the larger commercial poultry operations.