There are no symptoms of hepatitis B infection in babies. Because the baby is so young when he/she is infected with hepatitis B, the body’s immune system does not play a relatively obvious role in attacking the hepatitis B virus that invades the body, so the body’s liver function and the general shape of the liver are not significantly affected, and the body does not feel obvious symptoms. Only when the baby’s blood is drawn and tested for the five hepatitis B tests can the baby be found to be suffering from hepatitis B. The main thing to look for in the five hepatitis B tests is the first hepatitis B surface antigen, which will be positive if the baby is infected with hepatitis B. The surface antigen will also be accompanied by the core hepatitis B test. If you’re a big triple-positive, you’ll also have a positive e antigen, and a small triple-positive will be accompanied by a positive e antibody. Babies infected with hepatitis B will become chronically infected and will need to wait until adulthood, usually around the age of 10 or 30 or 40, before immune clearance may occur, leading to liver function damage and the appearance of related clinical symptoms.