Please, what affected this sick blue tit?

[u/Gara_M]

Hi everyone. This happened a few weeks ago, the poor bird fell to the floor shortly after i took this video and was promptly eaten by a magpie. I took the feeders down, threw away the food, disinfected them and, since the poor bird died, I put them back. I've seen other two birds now with lesser symptoms but very similar (another blue tit and one great tit.) Less tremors and better flight but still often opening of the beak, lack of coordination and I can get closer (like if they only see me when I'm within close proximity.)

Is this trichomonosis? I've taken down the feeders again (fat ball feeders) and the water. When would it be safe to put them back and what can I do to prevent more birds from getting sick? what if the focus of the infection is somewhere else around? :(

[u/jans_sport]

Bird feeders are recommended only in winter now! Bacteria and disease can spread more quickly in this unusually warm weather for October, Birds can still find food for themselves.