Cats generally do not scratch their ears. If a cat scratches its ears, it may be caused by ear mites, bacterial and fungal infections. Symptoms of itching, redness and swelling will occur. You need to take the cat to the pet hospital for examination and treatment, and provide regular epidemic prevention to the cat. Deworm and keep your cat clean and hygienic. Try not to let cats play in dirty environments or places with grass to avoid contracting the virus.