House finch disease?

This is worrisome: a pair of house finches has been visiting my sunflower seed tray. This afternoon, I took some photos and discovered signs of house finch disease.

The male, in bright red, seems to have discharge from his eye.

Three years ago, I had one with a severe case. As far as I know, he died of it.

This is a common respiratory disease of finches, as well as many others, from chickens to pigeons, even to hawks. It is caused by the bacterium Mycoplasma gallisepticum. In the wild, it mostly affects members of the finch family. Chickadees often carry antibodies without showing any symptoms of having had the disease.

The symptoms are:

... red, swollen, runny, or crusty eyes; in extreme cases the eyes become swollen shut or crusted over, and the birds become essentially blind. Birds in this condition obviously have trouble feeding. You might see them staying on the ground, under the feeder, trying to find seeds. If the infected bird dies, it is usually not from the conjunctivitis itself, but rather from starvation, exposure, or predation as a result of not being able to see. (Cornell)

This one seems alert and able to navigate still. He may recover, I hope.

Alternatively, he could have salmonellosis, or some other condition. Last time, in the end stages, the bird's feet were badly swollen, as well, a symptom I don't find in the description of either house finch disease or salmonellosis. This guy's feet look ok, so far, but his mate's feet don't look right.

She doesn't hold the perch normally. Otherwise, she looks fine.

More info from Cornell:

Although infected birds have swollen eyes, the disease is primarily a respiratory infection. It is caused by a unique strain of the bacterium Mycoplasma gallisepticum, which is a common pathogen in domestic turkeys and chickens. The infection poses no known health threat to humans...

I took action immediately; removed the feeder tray, and bleached it thoroughly to kill any germs. I won't use it again; it's got too many cracks where gunk can collect.

Cornell recommends also raking up dropped seed; I do this at least every second day, partly for neatness sake, partly because the sunflower shells attract slugs. I keep the bird bath scrubbed out, but usually don't use bleach, trusting to clean water and a good brush to prevent contamination. I'll be using bleach now, until I see no signs of disease.

A white-crowned sparrow at the same feeder shows no sign of illness.

More info:

• Index page for Cornell's discussion of House Finch disease, with photos.
• Project Feeder Watch
• Suite 101 article
• Stewardship Garden. A goldfinch suffering from the disease.
• A DC Birding Blog. Feeders and disease.