Stool sampling and testing should not normally take more than 2 hours. Stool sampling refers to routine stool examination, after sampling, it should be sent to the laboratory for examination immediately, usually within 1 to 2 hours, because with the prolongation of the sampling time, the stool is likely to be affected by pathogenic microorganisms, such as viruses or bacteria, which will affect the results of the stool examination. Moreover, if pathogens are already present in the stool, storing the stool for too long may lead to inactivation of the pathogens, which may also affect the test results. If it has been more than 2 hours since the stool sample was taken, it is important to re-sample the stool and have it analyzed as soon as possible in order to ensure the accuracy of the test results.