Yellow fever: symptoms
Last reviewed: 23.04.2024
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The incubation period of yellow fever is usually 3-6 days (rarely up to 10 days).
Symptoms of yellow fever allow us to distinguish the following forms of the disease:
- light;
- moderate;
- heavy:
- lightning fast.
In typical cases, yellow fever has a two-wave flow with three periods:
- initial febrile (period of hyperemia):
- period of remission with a decrease in body temperature:
- period of venous stasis (reactive).
Yellow fever begins, as a rule, acutely without prodromal phenomena. High fever develops within the first 24 hours. The rise in temperature is accompanied by chills, pains in the muscles of the back and limbs and a severe headache. There is nausea, vomiting.
Usually the body temperature drops to normal values by the end of 3 days, but with a heavy current, fever can last 8-10 days. Then the temperature rises again, usually not reaching the original high values. At the onset of the disease there are symptoms of yellow fever, such as: hyperemia of the face, neck and upper body, pronounced vascular injection sclera, eyelid edema, swelling of the lips, puffiness of the face ("amarilla mask"). Characteristic photophobia and lacrimation. The mucous membrane of the mouth and tongue are bright red. Patients suffer from insomnia. Appears nausea, vomiting with an admixture of bile. Pulse reaches 100-130 beats per minute, good filling; in the future develops a bradycardia. Arterial blood pressure is normal, the heart sounds are slightly muted. They reveal an increase in the liver and spleen, and it is possible that they are painful on palpation. In a general blood test, neutropenia and lymphopenia are detected. ESR is not increased. Proteinuria is characteristic.
With the beginning of icteric staining of the sclera, conjunctiva and soft palate, blood pressure decreases and cyanosis appears. The condition of patients is significantly deteriorating. Possible nasal bleeding, bleeding gums, in the vomit masses reveal blood. In severe yellow fever during this period, the patient may die. With a mild course, the remission phase begins, with the body temperature dropping to normal values, the general condition improves, nausea and vomiting cease, the face turns pale, the puffiness disappears. However, after a few hours, the patients deteriorate sharply, the body temperature rises rapidly. These symptoms of yellow fever indicate the transition of the disease in the most difficult period - venous stasis. Observed in about 15% of patients and characterized by the development of jaundice, hemorrhagic diathesis and acute renal failure. Detect bleeding gums, as well as nasal, uterine and intestinal bleeding. Against the background of a polymorphous rash, the skin develops hemorrhages. Often there is vomiting of coffee grounds. Blood pressure drops; heart tones are muffled: a pulse of weak filling up to 40 per minute. The patient's condition is often aggravated by kidney damage; show a decrease in diuresis. Oliguria can be replaced by anuria: the development of azotemia is possible. The amount of protein in the urine rises to 10 g / l and more, granular and hyaline cylinders appear. The blood levels of urea and creatinine are increasing. The liver is somewhat enlarged, painful. The amount of bound and free bilirubin increases, and the activity of aldolase and aminotransferases increases. The content of leukocytes is reduced to 1.5-2.5x10 11 in a liter of blood; there is neutropenia and lymphopenia. Slowing down the blood, increasing ESR. These changes are most pronounced on the 6-7th day of the disease - a critical period for the patient.
With a favorable course of the disease from 8-9 days, the general condition of patients gradually improves. There is a normalization of clinical and laboratory indicators. Asthenia persists for a week.
There are also possible forms of the disease in which the symptoms of yellow fever are absent. Diagnosis is established retrospectively using serological methods of investigation.
[Mortality and causes of death
Lightning-fast form leads to death on the 3rd-4th day of the course of the disease. Severe symptoms of yellow fever usually end with lethal outcomes on the 6th-7th day.
Death occurs with the development of acute renal, hepatic and cardiovascular insufficiency. Often identify symptoms of toxic encephalopathy.