The exact post-harvest losses are difficult to assess. Some examples based on surveys are given below which indicate the huge financial losses that have been found and can generally be expected. In large grain stores the situation may be even worse. At an estimated 50 gm one rat can destroy in one night appreciable losses will accumulate. It is impossible to put an exact estimate on these losses, but it is obvious that the damage caused by rodents is enormous.
Diseases transmitted by rats to man pose a serious public health problem in tropical countries.
Apart from causing human suffering, they are responsible for financial losses incurred through work-days lost and additional medical bills. While this topic is not directly related to post-harvest problems, it bears relevance to postharvest rodent control. As rodent pests in stores and households are controlled the rate of disease transmission will be reduced. Just as it is difficult to put exact figures on losses caused by rodent pests, it is not easy to estimate the exact benefits of rodent control. However it is apparent that rodent control is mostly if not always cost effective.