This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infectious disease, Subject name: Pediatrics
[{'content': 'Which is not given at the time of bih? \nSelect and explain. \nA. OPV, B. BCG, C. Hepatitis B, D. HiB', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Routine vaccination of Hib vaccine is staed at the age of 2 months of age. The vaccine is usually given in infancy as repeated doses together with DPT vaccine. A time lag of 8 weeks between any two doses is ideal. A booster is recommended at 12-18 months of age. Reference: Ghai essential pediatrics 6th edition Page 197', 'role': 'assistant'}]