We have proposed a model considering two equally sized population (group A and group B) with low and high levels of disease tolerance. We have argued that in the more tolerant group (group B) the progression of the disease with respect to time will be slow with lower number of infections at any given time. We attribute this effect to the innate immunity which advantageously, can also be one of the major contributing factors for flattening the curve. We have compared the growth of Covid-19 disease in various countries to understand this effect.