4. Decreased or loss of appetite
It’s not surprising that a person’s appetite would wain significantly when their mouth has become a bubbling island of volcanoes. Sometimes it’s the pain that causes a change in eating habits, but sometimes it’s a change all on its own, whereby the illness tells the body it doesn’t need to take on any food. It’s like a system hijack with the virus at the helm, well aware of what would improve the body’s ability to fight back.
Vitamins, nutrients, and energy obtained from food would be more power in the body’s armory and so the virus decreasing a person’s appetite is a way of fighting back. A declaration that the virus has found a nice place to live and doesn’t fancy the idea of some repowered sickness fighting cells stocking up at the canteen. You could maybe interpret a decrease in appetite as a final throw of the dice from the victim. It must be ignored and food must be taken on if this is a fight that the patient is going to win.