I’m sorry I want to ask if the baby doesn’t have an injection how much does it do ???
Immunization is very important for babies. Immunization can prevent disease. BCG immunization serves to help prevent TB disease. Tuberculosis is a disease caused due to a bacterial infection that is transmitted through respiratory air. TB can affect both infants and adults. so that if you don't get BCG immunization, your child can easily get TB.
Ideally, BCG immunization should be carried out before the child is 2 months old. However, if the age of 3 months has not been immunized against BCG, then your child can get BCG immunization, but before that several tests must be done first, such as the tuberculin test.
Therefore, you should bring your child to be checked by a pediatrician, so that the doctor can further check the condition of your child.
Here's an article you can read about the BCG vaccine
may be useful. thank you