I'm sorry to say but it looks like its columnaris. I've had many tetras (specifically red eyed tetras) that have gotten this disease. I've had a few survive but it's unlikely. Usually what works the most is to isolate them ASAP. Columnaris is very contagious usually with a single species that schools. In their isolation tank use aquarium salt, not marine salt, and any medication that cures ich. Hope your fish makes it. Good luck.
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