An ongoing bird flu outbreak that has devastated the U.S. poultry and egg industries seems to be leaving backyard chicken farms mostly untouched in what experts are calling an epidemiological mystery.
Bird flu is a highly lethal strain of influenza that can kill a bird or human within days. Fortunately, the disease is not transmitted very easily, and it only tends to infect human beings who work in close contact with birds. However, epidemiologists fear that the flu could be only a mutation or two away from a strain that spreads easily from person to person.
When birds are kept in close quarters, as in factory-farm operations, the disease can run wild. For this reason, the standard practice among poultry operators has been to kill an entire flock at the first sign of infection.
The current North American outbreak is the biggest in history, and it has led the poultry industry to kill 40 million birds in Canada and 16 U.S. states.
Conventional wisdom overturned
According to data from the U.S. Department of Agriculture (USDA), as of May 14, only about 10 percent of confirmed bird flu cases have come from backyard operations.
This is true even though the official response to any confirmed case is to search the surrounding area for birds (including people’s homes) and then quarantine and test any birds found, including those in backyard flocks.
In Iowa, for example, all flocks within 6.2 miles of an outbreak are tested. Of the 400 flocks tested to date, more than half have been backyard operations. Yet the trend continues: it’s the factory-farmed birds getting sick.