What is Mantoux test? And can a child of 2 years+ still do the test?
And if he has no immunity to tuberculosis will he still receive the BCG?
Yes a 2 years old can still take BCG Vaccine.
The first thing to do is check if the child is immunized that is has developed response despite the NO SCAR.... this is by doing a Mantoux test... If the response is compatible for a child who has received BCG that is okay. There is no need to worry about the scar.