Hives may not be viral at all. It is very hard to figure the trigger, food, dust, medicine. I would recommend yoy read the website called hereditaryangioedema.com. It seems a very small number of people have a genetic defect of CH-1 inhibitor factor in their blood. This results in the giant hives. Thats why antihastamines have no effect on these peoples hives. The defect is in the blood, hereditary.