You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Endemicity of a disease means: and explain in detail?
Endemic Is the constant presence of a disease agent in a defined geographical area ; refers to 'usual or expected frequency' of a disease in a population. For instance, common cold is endemic because somebody always has one. Endemic diseases in India are : Measles, mumps, rubella, chicken pox, peussis, TB, HIV, Cancers, diabetes, hypeension etc. Epidemics can arise from uncontrolled endemics also.