Some infections can affect overall condition and, in turn, coat quality. A dull coat in cats may indicate underlying issues, including infections, especially when paired with appetite or energy changes (Ding H, 2017). It’s not that the coat is the problem—it’s that the coat is a visible place where the body’s “off days” show up.
If you suspect illness—feverish warmth, hiding, vomiting, diarrhea, coughing, eye/nose discharge, or sudden coat change—treat it as a veterinary moment rather than a grooming project. Once the underlying issue is addressed, the coat often improves as hydration, appetite, and normal grooming return. Your role is noticing early and keeping care steady, not guessing at diagnoses.