Dengue fever is a viral disease which is caused by a virus of 4 types. Each type of the virus causes the fever that in the majority of cases ends with recovery. After treatment, the patient acquires a strong immunity only to the type of virus that caused the fever. This means there is a risk of re-infection with another type of the dengue virus.
The symptoms of the dengue fever depend on the form of the disease. Let’s review them in turn.
The classic form is characterized by a benign course, i.e. without the development of the hemorrhagic syndrome. Characteristic symptoms of this stage are as follows:
two-wave nature of fever. Body temperature rises to 38-41ºC on the first day after the end of the incubation period. After 3-4 days the temperature drops to a normal level and then a second temperature peak occurs.
a runny nose;
inflammation of the eye mucous membrane covering;
a headache along with pressing pain in the eyeballs;
pain in muscles, joints, spine, and limbs. Severe pain immobilizes the patient completely.
disturbed sleep, loss of appetite and bitterness in the mouth;
swollen lymph nodes;
vomiting and impaired consciousness are also possible;
a rash appears on the 5-6 day. Initially, it localizes on the breast, an inner surface of the shoulders and then spreads to the torso and limbs. The rash is of the red color and is accompanied by itching.
Haemorrhagic form or Dengue Hemorrhagic Fever (DHF) has the following characteristic signs:
a two-wave character of fever;
strong shaking ague, headache, sore throat, and cough;
unlike the classical form, muscle and joints pain is rare;
swelling of the face and redness of the mucous membranes;
the rash develops on the 3-5 day on the body and spreads to the face and limbs. A rash is accompanied by severe itching.
pain in the stomach area or all over the belly, often accompanied by vomiting (sometimes with blood);
abundant and watery stool may appear;
enlargement of the liver that becomes painful during palpation.
After 2-7 days the body temperature may normalize meaning the beginning of the recovery. In case of a heavy course of the disease, the patient’s condition may rapidly deteriorate and dengue shock syndrome occurs. This is a pathological condition provoked by a decrease in circulating blood volume due to the loss of liquid as a result of bleeding and/or abundant watery stools. It is manifested by the following signs:
the sharp drop of arterial blood pressure;
loss of consciousness;
suppression of reflexes;
skin is cold, pale and of bluish shade;
convulsions of separate muscle groups;
pulse is very weak or barely determined.
The duration of shock is small. The patient may die within 12-24 hours. Recovery occurs quite quickly after the anti-shock measures despite the severity of the condition.