A very high fever can be extremely dangerous. If you're an adult and your fever reaches above a temperature of 103 °F (39 °C), go to an emergency room or an urgent care facility for testing. You may need prescription medication or hospitalization.  For infants under 3 months old, contact your doctor if they have any fever at all. It could be a sign of a serious infection. Children from 3-12 months should see their doctor if they have a temperature of 100.4 °F (38 °C) or higher. If they're 3-12 months old they should be seen if they have a fever of 102.2 °F (39 °C) or higher, as well as if they're under age 2 and have a fever that lasts longer than 48 hours. Children aged 7-12 should go to the emergency room if their fever reaches above 102 °F (39 °C). A fever is your body’s natural way to eliminate illness. But a fever that continues could be a sign of a deeper or more serious problem. If your fever doesn’t go away after several days, even after trying to get rid of it, call your doctor. They may suggest that you seek emergency treatment or they can prescribe medication that can help. If your fever lasts longer than 48 hours, call a doctor. It could be a sign of a viral infection. A high fever can cause your body to lose fluids and could lead to dehydration. If you begin to feel symptoms like dry mouth, sleepiness, little or dark urine output, headache, dry skin, dizziness, and faintness, get to an emergency room or an urgent care clinic immediately. Your emergency care team may administer IV fluids to rehydrate you. If you have a disease such as diabetes, anemia, a heart condition, or lung disease and you develop a high fever, you need to get checked out by a doctor. A fever is much more dangerous if you already have a condition that could be exacerbated by a fever. If you’re concerned, call your primary care doctor to be sure of what you need to do. If you develop a skin rash or you see bruises that you can’t explain and seem to have come out of nowhere, contact your doctor. It could be a sign of a serious...

How would you rephrase that briefly using Chinese?
如果体温达到39-41摄氏度，立刻寻求紧急治疗。 如果发烧迟迟不退，一定要联络医生。 出现脱水症状时，一定要寻求紧急治疗。 如果你本来就患有某种疾病，发烧时一定要去看医生。 如果你在发烧期间起皮疹或出现淤青，一定要联络医生。