Common diseases in kittens include, one is gastroenteritis, because kittens have very shallow stomachs and do not know how to control their food intake. If the pet owner does not feed properly, it will easily cause gastroenteritis in cats. The main symptoms are: There are symptoms such as diarrhea, vomiting, and fever; the second is colds. Kittens have relatively low immunity, so they are more likely to catch colds. The main symptoms are coughing, sneezing, runny nose, fever, and lack of energy; the third is ear mites. Their resistance is weak, so they are more likely to get ear mites than adult cats. If the pet owner finds that there is oily or dry flaky brown-black dirt in the ears of the kitten, and the cat often scratches the ears with its hind legs, it is likely to be ear mites.