Host Defences

Naturally when the immune system encounters a virus it produces specific antibodies that can bind to it and eliminate it. Antibodies present in the blood samples may be used to determine if the person has been suffering for the specific  infection. The second way of defence is may be by the cell mediated and humoral immune response by the production of B cells and T helper cells. The immune system holds the retention of the infection hence a second encounter of the same virus is prevented and eliminated.