Laboratory testing shows that flies exposed to a food source infected with exotic Newcastle disease (END) can pick up the virus and carry it for several days, perhaps later passing it on to chickens that eat the food.
“Flies can carry END virus and evidence is mounting that flies may be able to transmit the virus between chickens,” says Alec Gerry, UC Riverside assistant veterinary entomologist.
END is a contagious and fatal viral disease affecting the respiratory, nervous and digestive systems of poultry and other birds.
“END is so infectious that many birds die without ever showing signs of illness,” Gerry says.
In 2002 and 2003, an END outbreak in California resulted in the quarantine of nearly 20,000 buildings, the destruction of 3.2 million birds, and eradication efforts that cost $170 million.
UC Riverside postdoctoral associate Seemanti Chakrabarti found that flies (bronze blow fly, housefly and little house fly) routinely contract infectious END virus at locations where chickens are also infected. Presumably, flies are making contact with the virus when they land or feed on poultry manure containing the virus.
“Conservatively, flies should be considered as transmitters of the END virus,” Gerry says. “This means that fly control should be an important part of a biosecurity program at all poultry operations.”