Very few humans have gone up against bird flu. But we've all dealt with seasonal flu for years. Some of our immune systems might be primed to fend off a worse case, research finds.

Thus far, this strain of bird flu has been spread primarily due to contact with infected birds, their excrement, saliva, or feathers ... rolled out a new plan late in February to help poultry ...

There have not been reported cases of someone contracting the disease from down feathers. The CDC also says birds infected with avian flu spread it through their saliva, mucus, and feces.