After immunization, it's normal for babies to experience fussiness and intermittent crying. A low fever and soreness might follow. A warm compress applied after the shot can help reduce soreness. You can also try moving the thigh in which the shot was administered -- do the "bicycle" to help bring relief.
If baby is crying for more than 3 hours at a time, has a super high fever of more than 40 degC, start convulsing - please rush baby to the doctor.
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