I think you did right. I have also not heard of Coccidiosis not responding at all to Corid after several days. And I think at the stage Anna is at she needs help quickly.
I have suspected Mycoplasma in my flock and read a bit about it at the time. I had one hen with bubbles in her eyes and four chickens with very swollen faces, and sneezes. I didn't treat any with antibiotics because their behaviour were otherwise completely normal. Just rinsed the eye and checked that they had no difficulty breathing. Those symptoms disappeared by themselves, but now I do have most of my birds sneezing a few times a day.
I suppose you know that the antibiotics treat the symptoms but do not eliminate the bacteria, that birds can be asymptomatic carriers, or develop symptoms that range from light to deadly, and that stress tend to make them develop symptoms.
I would personally not treat Ida with antibiotics just for sneezes, and keep the Baytril for when she really needs it. Enrofloxacin seems to be a very effective and wide range antibiotic. My view is that those must be used sparingly to preserve their efficiency. It's a personal choice. I think you can wait one day or two to see the evolution.
Not sure you see my post before you run to the store, but just in case, I would suggest getting also some powder. My chickens utterly hate the spray and it becomes more and more difficult to use it on them, whereas they don't mind the pyrethrum/ geraniol powder or the neem oil.
If you had tapeworms in your flock, you would know, believe me. They reproduce by shedding live segments through feces so it's not like roundworms, you can't have them without knowing, unless you never look at a fresh poop (after a while the segments move away).
Sorry for the yuck! A few Monday mugs.
Laure
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Pied beau
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Piou-piou
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Nieva (both a mug and a thirst pic!)
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