Small interventions to prevent spread of bird flu
Researchers at the Royal Veterinary College (RVC) have analysed the live bird market in Asia, and how it supports the spread of H5N1 avian influenza, finding that it could be a permanent source of poultry and human infection.
Dr Guillaume Fournié and colleagues at the RVC interviewed live poultry traders in northern Vietnam and constructed contact networks and a disease transmission model based on the movements of traders.
The resulting report found that it constitutes a “highly interconnected network” that can support large-scale disease transmission, and that this transmission can potentially spread to outside uninfected regions.
“Depending on trading practices, they may amplify and sustain the virus circulation, and therefore become a permanent source of infection for the poultry sector, as well as for humans,” the report said.
Researchers recommended a number of small-scale interventions at “key hubs” within the network of poultry traders, such as daily disinfection of trading areas, vehicles and equipment. They found these measures could “dramatically disconnect the network” and prevent disease spread.
“Alternatively, thorough and frequent hygienic measures and changes in the management of marketed birds – especially the reduction in the length of time birds remain in markets – may be more realistic and sustainable strategies,” the report added.
Researchers hoped these recommendations would mean disease control measures undertaken in the past could be avoided. Vaccination, culling and movement restrictions were “not realistic in resource-poor settings dominated by smallholder poultry farms”.
“While their official banning may appear as the best option at first sight, the enforcement of such a policy is challenging in low and middle countries where live bird markets are widespread.”