Transport of Moving Duck Flocks in Indonesia and Vietnam: Management Practices That Potentially Impact Avian Pathogen Dissemination.

Highly pathogenic avian influenza (HPAI) virus is endemic in Indonesia and Vietnam, where "moving" duck production is commonly practiced. Questionnaire surveys were conducted with transporters of "moving" duck flocks in Indonesia ( = 55) and Vietnam ( = 43). The main purpose of transportation was to transport duck flocks between rice paddies used for scavenging.

Characteristics of two duck farming systems in the Mekong Delta of Viet Nam: stationary flocks and moving flocks, and their potential relevance to the spread of highly pathogenic avian influenza.

Ducks are considered to play a major role in the spread of highly pathogenic avian influenza (HPAI) H5N1 in Viet Nam, but detailed information on their management is limited. We distinguished two different systems (1) stationary duck flocks that are not commonly driven to rice fields beyond village boundaries and that are confined overnight on farms and (2) moving duck flocks that are intentionally driven to rice fields beyond village boundaries, that are not returning to home farms for extended periods and that are housed overnight in temporary enclosures in rice paddies. A total of 115 stationary and 22 moving flock farmers were interviewed in 2007 in the Mekong Delta of Viet Nam.

Risk factors and characteristics of H5N1 Highly Pathogenic Avian Influenza (HPAI) post-vaccination outbreaks.

Highly pathogenic avian influenza (HPAI) virus H5N1 is now endemic in South-East Asia but HPAI control methods differ between countries. A widespread HPAI vaccination campaign that started at the end of 2005 in Viet Nam resulted in the cessation of poultry and human cases, but in 2006/2007 severe HPAI outbreaks re-emerged. In this study we investigated the pattern of this first post-vaccination epidemic in southern Viet Nam identifying a spatio-temporal cluster of outbreak occurrence and estimating spatially smoothed incidence rates of HPAI.