It takes about a week for symptoms to appear after an individual is infected. The symptoms presented by those infected with dengue determine its severity and the treatment plan. After you've been bitten by a dengue-infected mosquito, symptoms will appear typically four to seven days later. These symptoms generally last about three to ten days. There are two major classifications of dengue: without and without warning signs.  Dengue without warning signs is usually identified by the presence of a fever (40 degrees Celsius/104 degrees Fahrenheit) and two or more of the following: nausea or vomiting; a rash that causes the face to redden and red patches to develop on arms, legs, chest, and back; body ache and pain; low white blood cell count; swelling of glands in the neck and behind the ear.  Dengue with warning signs is classified similarly to dengue without warning signs, but patients in this category exhibited one or more of the following: abdominal pain; persistent vomiting; fluid accumulation in abdomen and lungs; bleeding from gums, eyes, nose; lethargy or restlessness; enlarged liver.  Such warning signs indicate that the dengue infection may be serious and could progress to associated bleeding and organ failure, or what is called dengue hemorrhagic fever (DHF). If one or more of the above symptoms are present, the subsequent 24-48 hours of dengue infection could be lethal without proper hospital care. Severe dengue includes symptoms from both of the above classifications along with any of the following:  Severe bleeding or blood in urine Severe fluid accumulation in abdomen, lung Loss of consciousness Involvement of other organs, such as heart, leading to further fluid accumulation, low pressure, high pulse rate If any of these symptoms are present, take the person immediately to the nearest hospital. All patients with severe dengue or dengue that presents with warning signs should go to the hospital as soon as possible. Those who present without warning signs should also visit the hospital for a...

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Write a summary of the previous text in Vietnamese:
Nhận biết thời gian ủ bệnh. Quan sát xem người bệnh có dấu hiệu cảnh báo nghiêm trọng không. Xác đinh xem bệnh nhân có bị sốt Dengue nghiêm trọng hay không. Đi bệnh viện. Xác định phương pháp điều trị và chăm sóc bệnh nhân.