Damage to thymus in a child may lead to

Our immune system's main gland is the thymus. The thymus is responsible for a number of immune system tasks, including the creation of T-lymphocytes, a kind of white blood cell that plays a role in cell mediated immunity. Immunity in which specialised cells carry out defensive functions is known as cell mediated immunity. They defend the body against any disease causing foreign particles that have invaded the cells of the host. Thus, any damage to the thymus will inhibit the formation of effector T-cells, causing loss of cell mediated immunity.