sick weak chicken what do i feed?

[chickmama8]

The sick chicken is eating and drinking but still unable to walk. she has been wormed and she is on day 3 of corid. she cant stand up at all. its like her legs wont work. she kicks them to move around on the floor but doesn't get up. I don't think she is going to make it. poor girl.

 

[chickmama8]

I have been reading other posts about the same symptoms that my hen has. could it be mareks and how can I tell for sure? I don't have a large animal vet in my town to take her to. My husband is not going to allow me to spend a lot of money on this hen either. I don't want her to suffer. She cant get to her food on her own I have to put it right in front of her and I have to give her water from a syringe.
help please. if it is mareks what do I do about my other hens? so far they are showing no symptoms of any illness. thank you. im very discouraged.