Infants and children who have regular contact (such as living in the
same house) with someone who has active (infectious)
tuberculosis (TB) have an increased risk of becoming
infected. It is extremely rare for a fetus to become infected before
immune systems quickly produce the tiny capsules
(tubercles) that surround and wall off (encapsulate) TB-causing bacteria in the
lungs. This process may cause extensive lung damage. Often a TB infection in
infants quickly becomes active TB. In infants, it is also common for the
disease to affect other parts of the body in addition to the lungs. Therefore,
an infant who is found to have a TB infection needs to be treated as soon as
possible. TB usually does not spread outside the lungs in older children unless
they have weakened immune systems.
Children who have active TB who complete an entire course of
treatment usually recover fully.