Question about disease in the ground.

Chatting to an old friend (ho does not keep hens) today he was telling me about his neighbour that had kept hens and that they got a disease that killed them and lived in the ground of his poultry run. Does anyone know what this might be? The reason I ask is that this same neighbour is possibly looking for a new home for 3 of his ducks and I'm wondering if this problem could be transferred via the ducks to my hens and ducks.

Sorry to be so vague but any information or opinions would be of value. Of course I will ask more detailed questions if the ducks are eventually offered to me.

Organic material like wood chips etc if not dug out, can get anaerobic bacteria Clostridium botulinum (aka limberneck). Death is rapid.

Thanks for the replies. Do you know how botulism is spread...so for example if these ducks came to live with me in my lovely grassy paddock where they would have clean water and Savoy standard living accommodation would the botulism live in the ground from their poo to be spread among my flock or would it stay behind in the original run? Of course all still hypothetical as I've not been offered these ducks yet.