Migratory birds not necessarily carriers of avian flu

Migratory birds should not be immediately blamed for the avian influenza virus (AIV) that hit the provinces of Pampanga and Nueva Ecija recently, a conservationist said.

“Avian influenza in the Philippines is not traceable to migratory birds. Do not blame the migratory birds as they are victims, too (of the infection),” Carlo Custodio, a consultant of the Department of Environment and Natural Resources-Biodiversity Management Bureau (DENR-BMB), said in a roundtable discussion last month organized by the National Research Council of the Philippines.

Entitled “Avian Influenza – How do we Prevent its Entry and Spread: Policy Implications Towards Early Detection, Management and Mitigation,” the forum was held on Sept. 26 at the Bayleaf Hotel in Intramuros, Manila.

Custodio explained that avian flu was first recorded in the Philippines in 2006, after which the country was free of bird flu for more than 10 years – lessening the possibility that migratory birds are a possible vector of the virus as migration happens every year.

He said that global multi-agency Scientific Task Force on Avian Influenza and Wild Birds had issued a statement against unjustly and unfairly blaming wild birds for AIV incidences around the world.

He said that a key message of the Scientific Task Force’s statement issued in December 2016, particularly on the H5N8 Highly Pathogenic Avian Influenza, was that typically, HPAI outbreaks are associated with intensive domestic poultry production.

The task force has said that attributing the spread of HPAI viruses to wild birds has resulted in mortality and conservation issues.

“The specific role of wild birds particularly in the long-distance transmission of the virus, if existent, remains unclear,” Custodio said, reading the task force’s Dec. 20, 1996 statement.

Custodio said that the Scientific Task Force had urged countries, agencies and organizations to “focus disease prevention on biosecurity at poultry holdings and in marketing systems, and disease control actions on affected farms and zoos, with the aim of minimizing the risk of disease spread to other poultry farms, zoos and/or wildlife by preventing poultry/captive-bird-wildlife contact.”

The task force, he said, urged countries, agencies and organizations “to recognize their international obligations and ensure that there is no consideration of killing wild birds, spraying toxic products or negatively affecting wetland habitats as disease control measures.”

He said focusing attention on wild birds, to the exclusion of other potential routes of transmission, can misdirect critical resources away from effective disease control and result in continued spread among poultry populations and economic losses to farmers and national income, as well as negative conservation and health outcomes and loss of biodiversity.

The outbreak caused the culling and destruction of at least 500,000 poultry stocks in affected farms in Pampanga and Nueva Ecija.

Scientists and researchers, however, recognized that there should be a collaborative effort to identify the origin of bird flu.

“We need scientists who we could collaborate with in conducting research on the traceability of the virus origin because we cannot do it alone on our level,” said Dr. Maria Glofezita Lagayan, veterinarian and a member of the Avian Influenza Task Force of the Department of Agriculture’s Bureau of Animal Industry, who served as one of the resource persons.

Lagayan added that enforcement of biosecurity measures in small private poultry farms is also weak because farm owners normally go to private veterinarians who do not have training on such measures prescribed in the Avian Influenza Protection Program Manual of Procedures of 2016.