RESUMEN
In the nineteenth century recurrent epidemics of cholera and influenza and decreasing cases of diseases in later years produced the question why communicable disease would suddenly produce epidemics and then disappear. Designing one model bases mathematically such as SIR model has been done for the question response. The aim of research survey model has been done on the measles in Iran and determination of outbreaks of measles at 1996 to determine the least vaccine covering for prediction of measles epidemics in the future.With collection, of data from disease control centers, the number of suffering with measles, age mean of measles and life expanse was calculated and the amount of R [Basic Reproduction Rate] resulted. Calculating R amount at range 5.5 to 7.49 for the reason R0 resulted in amounts greater than the measles epidemic that occurred in our country and least effective vaccine was 81.8-86.65%.Calculating R and the least vaccine predicted for measles epidemics determined that epidemic control vaccine must be more than 82.65% to decrease herd immunity and increase measles age mean under conditions due to another epidemic in the 2005