Dengue NS1 Antigen Quantitative, Serum
Test Overview
Dengue NS1 Antigen Quantitative is a blood test that detects the Non-Structural Protein 1 (NS1) antigen of the dengue virus in serum. NS1 can be detected during the early phase of dengue infection, making this test useful for early laboratory diagnosis, particularly during the first few days of fever.
Sample Required
-
Specimen: Serum
-
Sample type: Blood
-
Preparation: Usually no special preparation is required.
When is the test recommended?
- Fever with suspected dengue infection
- Early stage of illness, especially day 1–5 of fever
- Fever accompanied by headache, body aches, rash, nausea or other symptoms suggestive of dengue
- When early confirmation is clinically required
WHO guidance identifies NS1 antigen detection as an important method for diagnosing dengue during the acute/febrile phase.
What does the test detect?
The test detects dengue NS1 antigen, a viral protein released into the bloodstream during dengue infection. A positive NS1 result supports the diagnosis of acute dengue infection.
Result Interpretation
-
Positive: NS1 antigen detected; supports an acute dengue infection.
-
Negative: NS1 antigen not detected. A negative result does not always exclude dengue, particularly depending on the day of illness and the assay used. Further testing such as dengue IgM/IgG or molecular testing may be considered based on clinical timing and physician advice.
-
Quantitative value: The numerical result and its interpretation depend on the assay methodology and laboratory-specific reference limits.
Important Note
NS1 testing is most useful during the early phase of illness. As the illness progresses, antibody-based testing such as Dengue IgM may become more useful. Test selection should consider the number of days since symptom onset and the patient's clinical condition.
Clinical Significance
Early detection of dengue can support timely clinical evaluation and monitoring. However, the test result should always be interpreted along with symptoms, duration of fever, platelet count, hematocrit and other relevant investigations by a qualified healthcare professional.
