Health secretary RFK, Jr. has repeatedly suggested that farmers should let bird flu spread through flocks. Experts explain why that’s a dangerous idea

One of the ways it can spread to healthy poultry farms is by a single infected duck visiting a flock and shedding the virus through feces. H5N1 kills relatively quickly, causing respiratory distress, swelling, lack of coordination and other symptoms before death. (Culling is therefore considered more humane.)

Stray feathers litter the ground inside the empty coop at Kakadoodle Farm. A few beige eggshells crunch underfoot. No hens were left alive.