You should not eat crab during fever. Crab is an aquatic animal and cold food. If you eat too much crab during fever, it will lead to a cold body and aggravate typhoid fever. If you eat crab during fever, you will have diarrhea, abdominal pain and other adverse reactions due to low gastrointestinal function and weak spleen and stomach. Crab is a high-protein food, and if you eat too much high-protein food during fever, it will lead to an increase in body heat and aggravate the symptoms of fever. In addition to crab, you should also be careful not to eat seafood, squid or shrimp during fever. Try to maintain a light diet, avoid spicy, cold, greasy stimulation, and eat more fresh fruits and vegetables to replenish vitamins. Avoid high-protein foods to avoid increasing the burden on the stomach and intestines. You also need to drink more warm water, try to rest in bed during the fever, reduce outdoor activities, and take good care of your diet and life in order to recover as soon as possible.