Mareks disease in a vaccinated hen?

I have an americana hen about a year old. I noticed the other hens pecking her about a week ago. We brought her into the house and are keeping her in a box with food and water. She was limping at first and now has no use of either leg that I can tell. One leg sticks straight out when she tries to move and the other seems to stay tucked under her. I take her out to the yard (not with the other chickens) daily and let her hang out in a shady area for a couple of hours. She mostly doesn't move at all. I prop her up with a rolled towel on either side so that she is upright and doesn't get 'bed sores'. She was eating for the first few days (loved chopped almonds) but now shows no interest even in corn but still drinks water.

My question is whether or not this is certainly Mareks disease. She was vaccinated at the hatchery. She's about a year old. This wouldn't be typical for Mareks disease but the symptoms seems to fit. I cannot find an injury or sore spot on her feet.

Any help would be appreciated. I'm really worried about my other 13 hens too - 11 of them were vaccinated at the hatchery but I've got two wonderful seramas that I'd be devastated to lose. They are a couple of years old.

Lastly, what can I disinfect with that is effective against Mareks to minimize contamination to the area just in case?

One last question, I have a pigeon - can she contract Mareks? I don't know if the disease is specific to chickens and ducks or can spread further. I can't seem to get a definitive answer through a google search.

Thanks everyone!!!!

Cocci??? http://www.firststatevetsupply.com/content/view/16/43/

Could it look like Mareks disease with the stiff leg? I don't know.

The Vaccine is not 100% effective. It also has to be used within a time frame from when its mixed, so if that chick was at the very end, it may have been old.
The stiff leg is like mareks and the increasing paralysis is like mareks, but the only way to know would be to necropsy her. Your state poultry extension can help with that or a vet can do it....its sometimes worth it for beloved pets and if youre very worried about the others.
you can try to treat with some different meds but if it is mareks, just keep her comfortable, but she will likely die. She will probably eat and be Ok till she dies so you can give her some quality of life...but thats your call. I usually cull when they are in their own poop and cant take care of themselves.
Mareks is everywhere and some chickens are more susceptible to it that others. It is spread via feather dust, so keep her separate.
If you are very worried about your serama, you may want to put her down just to stop the dust from being around. But maybe try some sulmet for cocci first...and try something like an antibiotic in case its some sort of mycoplasma type...search out anything that causes progressive paralysis....but it really sounds like mareks to me...and that is 99.9% deadly. The leg thing is common in mareks. they sometimes begin by walking like a soldier a little.
Since she is vaccinated, its worthwhile to try a couple of things. There are holistic remedies as well. I tried once or twice but I never found that they worked on true mareks (diagnosed by UConn's poultry extension)
Sorry that you have to go through this...I know its pretty horrible.... good luck..

Thanks for the reply. I guess I wanted someone to tell me that it wouldn't be Mareks because I know that might cause havoc with the rest of the hens too. This hen is comfortable - I have her in a box with rolled towels to keep her balanced and out of her poop. I would cull her if I was sure the diagnosis is Mareks but without necropsy there doesn't seem to be a definitive test.

The only way to know is to treat her for other things that it may be...they dont always even see mareks on first inspection in necropsy; its actually tumors on the nerve endings...and Ive had them come to the conclusion of mareks by ruling other things out.
I find that they live along OK as long as you help them...and they dont seem all so aware that something is wrong. They only want to be outside and around grass and sun, with snacks...its just too bad that they cant be with their friends, so they need attention.
But its not a terrible way to go as long as you end it before it gets really messy...when gets bad then you will have to think of culling.
Just remember that they dont perceive things the way we do. They get alot of enjoyment from just the things that chickens do...they are hardy and unless there is real pain they dont react much. It seems to me that they just sorta keep going with whatever life throws at them...this is evidenced by a mareks bird that can only lift its head but is happily eating and pecking around when I put him out in the grass...
I dont think that there is pain. But its a lousy disease because its so fatal and so contagious...the vaccine is not stable and Ive had hatchery birds get it...silkies and polish seem more susceptible. the smaller, more hybrid birds seem to get it easier. So be careful with those serama!!
Hang in....

The Marek's vaccine does not prevent Marek's disease from being in your flock, but is supposed to help prevent the sypmtoms and death of your flock.

Your hen may have Marek's disease, but is not likely because of her age and the fact that she was vaccinated. If it is Marek's I wouldn't worry about the other hens showing symptoms at this age - typically Marek's disease will hit the weakest or most stressed of the flock, but doesn't hit them all with symptoms like a respiratory illness or other contagious disease would. Your hen may be suffering from something else instead - maybe something she ate (botulism), an injury, or another disease.

The last time I had a sick bird, a year or so ago, I took her to a vet and without any diagnosis or help other than culling my bill was $150. I think the 'exotic' animal vets around me are used to seeing parrots not chickens and charge accordingly.

I have antibiotic powders. One is "All-in-one" that contains ronidazole, tylosin, levaminsol, aprolium. The other is "puramycin" that contains tetracycline hydrocloride soluble powder. Do you know which of these would be more likely to help the hen?

Please read a bit on the following link. Marek's is highly contagious, and it's very unlikely that Marek's is the problem with only one grown, vaccinated hen affected.

I'd be looking to see it there was some moldy food that she might have gotten into. Even a tiny amount can cause paralysis.

http://edis.ifas.ufl.edu/ps044

having been through this and consulted extensively with the vet extension for my state, I can say that its possible to have one bird come down with it. Vaccinated birds dont get symptoms so if they are run down somehow they will get it and die. If a bird gets the tail end of the vaccinations in the hatchery, and the vaccination only lasts 2 hours when kept cold, after mixing, then they might not get the protection they need from it.
If one bird in a flock of vaccinated birds comes down with mareks for some reason (and the vaccine is not 100% effective) that doesnt mean that the others will suddenly get it!
Its best to remove the bird and keep the dander away from other flocks, but the disease is pretty much everywhere and its not like coryoza or certain mycoplasmas where one bird gets it and then the rest catch it and die all in a row!
Using antibiotics (and I would start with the broadest one) is only to check for it maybe being something else. I suggest having a necropsy done my a bird vet, state or otherwise, but many dont. Most people cull a lame bird immediately and ask questions later. If this is a pet and you want to see if it will recover, keep it in isolation and try some different treatments...antibiotics, sulfa, etc....just research things that can cause your symptoms and try different things. All being equal, it wont hurt to try...there are also "natural" cures but Ive found that they dont work.
Mareks is pretty usual...apparently chicks get some antibodies from the mother and flock so you cant vaccinate broody chicks, but I have had some broody chicks come down with it.
there are different strains also...so its hard to tell without a necropsy. I would keep the babies separate so as not to stress the hen and also to protect them.

Im not saying not to look for botulism or rotted food, but its pretty unlikely...and thats probably where you would see multiple chickens getting sick.
I havent had multiple chickens getting mareks since the very beginning of my chicken keeping when I was told by the hatchery that small flocks dont need vaccination...WRONG! That was then, and now they pretty much suggest it all around.