DENGUE FEVER – Signs, Prevention, Vaccine and Treatment

Image Courtesy of Mikael Häggström, some rights reserved.

Dengue fever is a virus-mediated fever caused by a dengue virus which is a Flavivirus. Five serotypes of Dengue virus are identified till now as DENV – 1, DENV – 2, DENV – 3, DENV – 4 and DENV – 5. It is a vector born disease like Zika and chikungunya transmitted by Aedes mosquito. The incubation period of Dengue Fever is 7 – 10 days. 15th June of every year is observed as International Anti – Dengue Day.


80% causes of dengue fever are asymptomatic. 20% virus-infected person shows signs of dengue fever like –

  • High-grade fever
  • Malaise
  • Severe Headache
  • Retro-orbital Pain
  • Arthralgia
  • Bone Pain
  • Nausea, Vomiting

Most patients usually recover within 8 days.


  • Bleeding like epistaxis, hemoptysis, gum bleeding, black stool, heavy menstrual bleeding
  • Recurrent and persistent vomiting
  • Convulsion or seizure
  • Severe abdominal pain
  • Sudden behavioral changes like restlessness
  • Cold clammy extremities
  • Metabolic acidosis
  • Ascites or pleural effusion
  • Increased haematocrit (HCT) > 45%
  • Respiratory distress


It is very difficult to differentiate Dengue Fever. ELISA based antigen detection test (NS1) used for diagnosis from day 1 of a fever today 5. IgM ELISA (antibody detection test) used for dengue diagnosis after the 5th day of fever. PCR ( Polymerase Chain Reaction) and viral antigen detection tests are more sensitive during 1st week of fever. Serial Platelet count and hematocrit determination are essential for the diagnosis of DHF ( Dengue Hemorrhagic Fever).

TOURNIQUET TEST – This is a clinical test. It is a type of capillary fragility test and often done in Dengue fever. The tourniquet test is done by inflating blood pressure cuff to a point midway between systolic and diastolic blood pressure and maintaining it for 5 minutes. The test is positive if petechiae are more than 10 per square inch.


Few cases of Dengue fever leads to hemorrhagic fever and Dengue Shock Syndrome.

  • Dengue Haemorrhagic Fever (DHF) – Haemorrhage occurs due to low platelet count. It is manifested by ecchymoses, epistaxis (bleeding from the nose) is haematemesis, black stool. It is a life-threatening fatal condition.
  • Dengue Shock Syndrome (DSS) – Due to hemorrhagic and plasma leakage patient may go into shock. shock is manifested by hypothermia, hypovolemia, feeble pulses, tachycardia, cold extremities. Here pulse pressure falls below 20mm Hg.


  • Pregnant women
  • Infants
  • Young Children
  • Hypertension
  • Diabetes mellitus
  • Hemolytic conditions
  • Obesity
  • Older persons


There is no specific treatment for Dengue fever. Symptomatic treatment is the most appropriate method of management. Fever, body-ache, myalgia, arthralgia are treated by acetaminophen. Due to the increased risk of bleeding aspirin, NSAIDs are avoided during Dengue fever. Platelet transfusion is considered in the case of severe thrombocytopenia. The isotonic intravenous crystalloid solution is given according to severity. Acidosis correction is done by using intravenous sodium bicarbonates.


We all know that “prevention is better than cure“. Mosquito control measures should be taken to prevent Dengue. Mosquito net, repellents are used to control adult mosquitoes. Wear loose and protective clothing for self-protection. Larvicidal chemicals can be used to kill mosquitoes larvas.

Dengvaxia is a live attenuated recombinant Dengue vaccine approve in May 2019 by US FDA for Dengue prevention. Dengvaxia is a tetravalent vaccine and given as a subcutaneous injection. It shows 60% efficacy in clinical trials. Seronegative vaccine recipients have an excessive danger of serious dengue compared to unvaccinated seronegative people.

10 Replies to “DENGUE FEVER – Signs, Prevention, Vaccine and Treatment”

    1. Hello,
      There is no specific medicine to increase platelet count only platelet transfusion is the treatment. Papaya leaves are under clinical trial but not proved yet .
      Thanks for your interest . Keep supporting .

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