This information came from the WAVD Consensus Statement on Diagnosing and Treating Dermatophytosis in Dogs and Cats. ✅️Comment “Derm” for a 9 page summary of it! For years we were taught that fewer than half of M. canis cases fluoresce. But many of us were probably not using a true Wood’s lamp (probably black lights) and that skewed the data. A black light emits a lot of visible blue light, which makes subtle fluorescence hard to see. A true Wood’s lamp filters out visible light and emits UV at