Patient: The female partner is a healthy carrier of hepatitis B virus and the male partner is healthy. The baby was born with high potency immunoglobulin and the 016 vaccination program. Now that the baby is more than 9 months old, can we go for a test to determine if she is a “non-carrier” and has developed antibodies? If it’s not easy to determine now, when is the best time to have the baby checked? Li Jun, Department of Infectious Diseases, Jiangsu Provincial People’s Hospital: The internationally and nationally recommended standard prevention program is for newborns to receive combined active and passive immunization after birth, which can effectively block more than 95% of infections. Your description indicates that your child is receiving such an immunization strategy. Your child can now be tested for the production of his or her own surface antibodies, and if effective levels of surface antibodies are still not produced, you are advised to consult with your local regular hospital for information about further booster immunization. Patient: Dr. Li, thank you! Li Jun, Department of Infectious Diseases, Jiangsu Provincial People’s Hospital: You’re welcome, and I wish your whole family good health and happiness! Patient: Please ask Dr. Li: If my baby is checked for antibodies and antibody levels, is a blood test the way to go? If I have to take a blood test, do I have to go in the morning on an empty stomach and not give my baby anything to eat, including water? Li Jun, Department of Infectious Diseases, Jiangsu Provincial People’s Hospital: Blood test is required, but not fasting. Patient: Dr. Li: The baby has been checked and only the five items are positive for antibodies and negative for the others. The test results are negative or positive, but there is no specific data on antibody levels. Please tell me: as long as the antibodies are positive, does it mean that the antibodies have reached a certain level and it is safe? Li Jun, Department of Infectious Diseases, Jiangsu Provincial People’s Hospital: The lack of quantitative test results may be due to the hospital’s testing equipment, which often has low sensitivity. Patient: It shows positive, it doesn’t say weak positive, so it should reach the protection level. Thank you for your answer! I wish you all the best!