Diarrhea in babies over 5 months old may be due to cold or infection with virus or bacteria. If it is symptomatic diarrhea after being cold, the number of stools may not be very high, and the color of the stools will be greenish, accompanied by the baby’s runny nose, cough and other symptoms. If the number of stools is very high, some as high as more than ten times, and the stools are also eggdrop soup-like or dilute watery stools, it may be infected with rotavirus enteritis, because babies more than five months old are the most common age for rotavirus enteritis, especially in the fall and winter seasons, and if eggdrop soup-like stools occur, fecal rotavirus testing should be conducted. If the baby’s stool still has sticky mucus like snot, or even blood, we should consider whether bacterial enteritis has occurred, and may be ingested bacteria, we should carry out routine stool tests, if there are more white blood cells in the routine stool, it can be diagnosed as bacterial enteritis.