I agree, after reading up on botulism some more, the website I sent you is the only one that mentions it as caused by a virus. I highly doubt now that this is what it is. I apologize if I got you worried. According to what I read, if it is botulism, she will die within 24 to 48 hours. The...
No, its not necessarily from the food - read this short article:
http://www.helium.com/items/1387367-poultry-diseases-botulism
Most likely she ingested it in the soil and it was activiated in her body because she carried the virus - if you read the article it explains it better, but I would...
I would isolate her just to be on the safe side. She could have botulism which paralyzes them or it could be nothing. ( I apologize if this is a repeat post - it looked like my first one did not go).
Please check the bottom of your duck's feet. She could have "bumblefoot" which is an infection. If there is a sore on her foot, it would cause her to walk funny.