Dengue Fever NS1 Antigen
Understanding Dengue Fever NS1 Antigen
What is Dengue Fever NS1 Antigen?
A Dengue Fever NS1 Antigen test helps to detect dengue, a viral infection caused by the dengue virus (DENV). This test detects the presence of the dengue NS1 antigen, a protein produced by DENV. It is used to detect the infection during the initial stages, thereby preventing disease advancement and severe illness.
Dengue spreads via the bite of an infected Aedes aegypti mosquito which carries the virus and commonly occurs in tropical and subtropical climates. Most of the infected people do not show any symptoms but for those that do, the most common symptoms include high fever, body pain, headache, nausea, and rash. Usually, these symptoms get better in about 1-2 weeks, but people who develop a severe dengue infection may need hospitalization, as severe dengue can be fatal.
Currently, there is no specific treatment available for dengue. Hence, early diagnosis with a Dengue Fever NS1 Antigen test is essential to prevent complications. If you have traveled to a place where dengue is common, get tested even if you do not have any symptoms. Also, reports state that dengue may also spread from an infected mother to her unborn baby. Expecting mothers should get tested if an infection is suspected. Appropriate measures like proper rest, drinking plenty of fluids, and regular monitoring of symptoms can help prevent disease progression and further complications. Usually, no special preparation is required for a dengue fever test; eat and drink as per your daily routine.
Test result ranges are approximate and may differ slightly between different labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. The results will help them determine your medical condition and formulate an overall treatment plan. Additional tests may be needed if you test negative yet show symptoms.
What is Dengue Fever NS1 Antigen used for?
A Dengue Fever NS1 Antigen test is done:
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For the detection of dengue infection.
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When you experience symptoms suggestive of dengue fever such as fever, body pain, fatigue, nausea, vomiting, rash, and pain behind the eyes.
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For differential diagnosis of flaviviruses and fever.
What does Dengue Fever NS1 Antigen measure?
A Dengue Fever NS1 Antigen test measures the NS-1 protein of the dengue virus. This protein is secreted into the blood during the infection, hence it can be detected during the early stages of the infection only. This test is sensitive for 7 days after the symptoms are experienced. After day 7, the Dengue Fever NS1 Antigen test is not recommended.
If left untreated, dengue fever may progress to a severe form such as dengue hemorrhagic fever or dengue shock syndrome.
Dengue hemorrhagic fever (DHF) can go to a higher grade. It might also include variable bleeding manifestations like bleeding from the nose, vomiting blood, passing blood in the stool, difficulty breathing, and cold clammy skin, especially in the extremities. During the second phase, the virus may attack blood vessels, causing capillaries to leak fluid into the space around the lungs (pleural effusion) or the abdominal cavity (ascites).
Dengue shock syndrome (DSS) is a severe complication of dengue fever that is caused when the body's immune system overreacts to the dengue virus. It can lead to a sudden drop in blood pressure and dehydration, and if not managed timely, it may lead to multiple organ failures.
There is no specific treatment for dengue, but early diagnostic testing, such as the dengue NS1 antigen can prevent the advancement of dengue to its complicated forms.
Interpreting Dengue Fever NS1 Antigen results
Interpretations
Result in index |
Remarks |
Negative (<0.9) |
No detectable dengue NS1 antigen. The result does not rule out dengue infection. An additional sample should be tested for IgG & IgM serology in 7-14 days.
|
Equivocal (0.9-1.1) |
Repeat sample after 1 week
|
Positive (>1.1) |
Presence of detectable dengue NS1 antigen. Dengue IgG & IgM serology assays should be performed on follow up samples after 5-7 days of onset of fever, to confirm dengue infection. |
Note: Recommended to do NS1 Antigen by ELISA in the first 5 days of fever. After 7-10 days of continuous fever, the recommended test is Dengue fever antibodies IgG & IgM by ELISA.