A family of flies that feed off of decaying flesh and feces can transmit highly pathogenic avian influenza (HPAI) to commercial poultry and wild birds, reports a study by researchers at Kyushu University.
The findings, published in Scientific Reports, reveal blowflies as a potential vector for HPAI and highlight a new target for halting the spread of the virus.
"By keeping areas clean and using fly control methods, such as fine nets or insecticides, we can reduce the risk of virus spread to indoor poultry farms. However, in outdoor farms in other countries, and in wild bird populations, controlling blowflies may be logistically impossible,” said first author and associate professor at Kyushu University’s Faculty of Agriculture, Ryosuke Fujita.
A new HPAI vector?
The research project collected and analyzed blowfly colonies found near wild crane populations in Izumi city, Kagoshima Prefecture, located in southern Japan.
During the winter, the dense population of migrating cranes makes them vulnerable to HPAI. HPAI has also been detected at poultry farms in the area, so the findings in crane colonies are also applicable to the commercial poultry industry, the researchers noted.
Of the 648 blowflies collected, 14 carried the bird flu virus. Genetic testing confirmed that the virus strain found in the blowflies in the same as the one infecting the crane colony.
"While 14 blowflies may seem like a low number, this represents a prevalence in blowflies of 2.2%, which is a huge percentage compared to other diseases spread by insects,” Fujita explained.
Blowflies ingest HPAI from infected dead birds or their waste, unlike other disease vectors like birds and mammals that become infected with the virus. The fly spreads HPAI to commercial poultry and wild birds by contaminating surfaces, food and water or by being eaten by fowl, the researchers hypothesized.
Future research will focus on the confirmation that blowflies are HPAI vectors at infected poultry farms and the development of new tools that use artificial intelligence (AI) to predict the potential risk of insects to transmit diseases.
View our continuing coverage of the global avian influenza situation.
