The MMR vaccine should be given when the baby is 18 months old; 8. The live attenuated B encephalitis vaccine should be given when the baby is two weeks old; 9. The group A+C flu vaccine should be given before the baby starts kindergarten. Some babies may have allergies after vaccination. Parents should stay at the vaccination station for a period of time after vaccination and wait until there are no abnormalities in the baby’s body before they can leave.