Bird Flu Is Slamming Factory Farms But Sparing Backyard Flocks. Why? – Tom Philpott

The Midwest’s ongoing avian flu crisis is wreaking havoc on the region’s large-scale egg and turkey farms. Last week alone, the US Department of Agriculture confirmed that the virus had turned up in more than 20 additional facilities in the region, condemning 4 million birds to euthanasia. Altogether, the H5N2 virus—”highly pathogenic” to birds, so far non-threatening to humans—has affected …