What do you mean by disease symptoms? Explain giving two examples.

Disease symptoms are evidences or presence of diseases. Symptoms are in the form of structural and functional changes in the body or body parts. They indicate and are signal for the disease that may show up in future if not treated on time e.g. wound with pus, oedema, cough, cold, loose motions, pain in abdomen, headache, fever. However symptoms do not give any exact cause of the disease. For instance, headache may be due to some dozen different diseases. There may be problem of eyesight, blood pressure, some sort of stress (such as of examination, meningitis, pollution, etc).