Endemicity of a disease means:
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.
Occurs clearly in excess of normal expectancy
Is constantly present in a population
Exhibits seasonal pattern
Is prevalent among animals
Time Distribution, Epidemics