Dear Dr. Roach: I have two bird feeders off of my back deck. They hang from tall poles as a vain attempt to keep the squirrels from eating all of the birdseed! But to refill them, I must take them down and handle them, and I recently wondered if I might be exposing myself to the new bird flu.

"The Chinese poultry lineage may have experienced more vaccine-driven selection compared to other lineages," the researchers wrote.

H5N1 vaccines have been previously licensed, and millions are in the national stockpile. But even with the news of the country’s first human death due to bird flu, vaccination isn’t yet recommended.