What does ringworm look like on a cat?

Infected areas usually appear as circular bald patches with scabbing and scaling, and some show red spots and red papules. As the disease progresses, the cat develops multiple bald patches and the infection spreads. Ringworm is a fungal infection, mostly from Microsporum canis or Trichophyton. Early infection may show only mild scaling that is not obvious, but parting the fur reveals clear abnormality. You can use a Wood’s lamp at home for preliminary diagnosis; Microsporum canis infections typically show apple-green fluorescence under the lamp.