Question
My baby is 38 days old and has swelling at the injection site on the arm after receiving the BCG vaccine. Also, redness and hardness are found under the armpit. What is the cause?
Answer
After BCG vaccination, regional hard lumps and inflammatory reactions may occur, at which point the wound should not be exposed to water. If you notice that the lymph nodes under the same armpit are swollen, causing hardness under the armpit with a diameter exceeding 1 centimeter, this is generally a normal reaction. However, if it exceeds 1 centimeter, medical examination and treatment should be sought.