If your temperature is 103°F (39.4°C) or lower, try to treat the fever at home, seeing whether it responds to at-home care.  If it's 104°F or higher, call emergency services or go straight to the emergency room; you may need immediate medical attention.  If your temperature has been 103 °F (39 °C) for at least 3 days, call your doctor. If the person's skin feels very hot to the touch, they are likely running a fever. Using this method, though, it's going to be hard to tell whether your temperature is at 98.7 °F (37.1 °C) or at 101.2 °F (38.4 °C). If the person feels hot to the touch, look for other symptoms or pick up a thermometer from a drug store to see if medical intervention may be necessary. A fever happens when your body raises its internal temperature in order to ward off harmful infections, viruses, or other maladies. Some research has even found that certain immune cells work better at these elevated temperatures. It's a natural defense mechanism. One significant result of this switching on of the body's heat switch is that patients can get or feel dehydrated.  Signs that you may be dehydrated include:  Dry mouth Thirst Headache and fatigue Dry skin Constipation   Dehydration can be made even worse if it is accompanied by vomiting or diarrhea. If you've experienced any one of these, especially, be sure to drink plenty of fluids to compensate for their loss. If you're struggling to drink fluids, try eating ice chips. In many cases, muscle aches are associated with dehydration, but they can be especially aggravating in a patient with the fever. Note: If your fever presents with back or muscle stiffness, call a doctor right away, as your condition may be related to a number of complications including kidney issues or bacterial meningitis, which can potentially cause brain damage. If your fever is at or above 104°F (40°C), you could experience some of the following in addition to hot flashes, dehydration, headaches, muscle aches, and general weakness. If you do experience any of the following, or have...

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Write a summary of the previous text in Vietnamese:
Theo dõi nhiệt độ cơ thể nếu có nhiệt kế. Thử tự cảm nhận làn da nếu nghi ngờ. Kiểm tra dấu hiệu mất nước. Kiểm tra dấu hiệu đau cơ. Kiểm tra dấu hiệu đặc biệt tồi tệ của cơn sốt. Đến bác sĩ khám nếu nghi ngờ.