1. Colds Colds are one of the common diseases in infants and are usually caused by viruses. Symptoms of colds in babies include runny nose, sneezing, throat irritation, fever, etc. Treatments for colds include keeping the room well ventilated, drinking plenty of fluids, gargling with salt water, and using antipyretics. 2. Diarrhea Diarrhea refers to excessive bowel movements or thin stools, usually caused by bacterial or viral infection. Symptoms of diarrhea in infants include diarrhea, vomiting, and abdominal discomfort. Treating diarrhea includes giving enough fluids and electrolyte supplements