Dengue: Symptoms, Diagnosis And Treatment

What Is Dengue Fever?
Dengue is a viral infection caused by the bite of female Aedes Aegypti mosquito. There are four serotypes of dengue virus.  Infection with anyone confers lifelong immunity from that particular strain but only partial protection against others. At present type 1 and type 2 strains are widespread in India.

How Does It Spread?

Dengue is spread by Aedes Aegypti mosquito that breeds in stagnant water. This mosquito can be identified by black and white markings over it’s body. Usually, it bites on the legs and arms and during day time.

What Are The Symptoms?

Dengue is commonly associated with high fever usually with chills, headaches, muscle aches and joint pains. The fever usually decreases around 3rd to 7th day of illness, which is followed by marked fatigue for days to weeks. In some cases, nausea ,vomiting and a rash can also occur.

What Is Dengue Hemorrhagic Fever?

In rare cases, a more severe life threatening disease called dengue hemorrhagic fever can also occur which results in bleeding, blood plasma leakage and rarely dengue shock syndrome.The World Health Organization has laid down criteria for diagnosis of dengue hemorrhagic fever. They are:Low platelet count (<1 lac), Fever 2 to 7 days, Hemorrhagic manifestations with positive tourniquet test.

What Are The Various Tests Available To Diagnose Dengue?

The diagnosis is usually established when there is sudden high fever accompanied by severe body, muscle or joint pain. In the lab, it can be established by the following methods:

1 .  Antibody Detection And Serology:  Dengue IgM and IgG antibody tests are usually done by ELISA. This test is usually positive after 5 to 7 days of illness. If this test is negative before 7 days, a repeat sample is taken from the recovery phase to confirm the diagnosis.You can get these tests done here

2 . Dengue Virus Isolation: It is the definitive test for dengue infection. It is useful only in early phase when blood is collected before day 5 of illness. But, the disadvantage is that it is expensive and time consuming and has a poor yield as compared to the molecular tests.

3 . Non Structural Protein (NS 1 ) Antigen Or Dengue Antigen – High concentration of NS1 antigen is found in the blood of dengue infected patients in the early phase. The sensitivity drops from day 4 to 5 of illness and usually becomes undetectable in the recovery phase.You can book this test here

4 . PCR: It helps in the early diagnosis of dengue infection (< 5 days of illness). Sensitivity is 100% in the first five days of illness but this test is also expensive and time consuming.

5 . Torniquet Test : A tourniquet is tied to the arm and if blood blotches appear beyond the tourniquet, the patient might be suffering from increased bleeding which may indicate dengue hemorrhagic fever.

6 . Blood Counts: A decreased platelet count may also occur in dengue fever ( normal level is between 1.5 to 4 lacs). Therefore, platelet count should be monitored carefully and regularly especially when the fever comes down.An increased hematocrit i,e. The volume percentage of red blood cells can also occur in some cases by approximately 20%. You can get your platelet count test done here

How Is Dengue Treated?

There is no specific treatment. The fever can be treated with antipyretic drugs like paracetamol to bring the temperature down and also to relieve body aches. Drugs such as aspirin and ibuprofen should be avoided as they may increase the risk of hemorrhage. Few home remedies like papaya leaves and kiwi are also quite popular in treatment of dengue fever as they have been known to increase the platelet count. Patients should drink lots of fluids as dehydration is a common symptom in dengue.

Is There Any Vaccine Against Dengue?

The world’s first dengue vaccine won clearance in Mexico in December 2015.The vaccine has been approved for patients aged 9-45 years and can thwart all four subtypes of the dengue virus. The vaccine has an efficacy of 60% more