Level 1: What is baby autumn diarrhea? Autumn is the season when babies are prone to diarrhea, usually caused by viruses, bacteria, etc. Your baby\’s intestines and stomach are not fully developed and their immunity is weak, making them more susceptible to infections. Diarrhea is characterized by increased stool frequency, watery stool, yellow-green or gray-white color, and is sometimes accompanied by symptoms such as fever and vomiting. Level 2: How to prevent autumn diarrhea in babies 1. Preservation