The dengue virus, which causes the disease, infects people when a mosquito bites them. The typical symptoms of a patient include high-temperature fever, rash, and discomfort in the muscles, bones, and area behind the eyes. The important period, however, from days 3 to 7, is when a small number of people may get severe dengue, which can be fatal. 

Dengue NS1 Antigen Test Overview 

The dengue virus, which causes the disease, infects people when a mosquito bites them. The typical symptoms of a patient include high-temperature fever, rash, and discomfort in the muscles, bones, and area behind the eyes. The important period, however, from days 3 to 7, is when a small number of people may get severe dengue, which can be fatal. 

What Do We Understand by Dengue-Antigen-NS1 Test? 

Dengue-Antigen-NS1 allows for the diagnosis of acute DV infection. Within 24 hours, the Dengue antigen NS 1 is visible and can last up to 9 days. Acute infection and dengue virus exposure are diagnosed using dengue-antigen-NS1. The detection technique is referred to as an enzyme-linked immunosorbent test. If a patient is suspected of having an acute dengue sickness, a clinician might request Dengue-Antigen-NS1 testing.  

The doctor must do the test if the patient's fever lasts longer than six days. Additionally, there may be signs of musculoskeletal discomfort, migraines, retro-orbital pain, or a brief macular rash. In youngsters, these symptoms are more common. 

How Dengue NS1 Antigen Diagnoses the Illness? 

The enzyme-linked immunosorbent assay (ELISA) test for dengue NS1 antigen aids in the identification of the virus in the blood. The dengue NS1 antigen, a protein produced by the dengue virus, is tested for in this test. A human can get the dengue virus from an infected mosquito. It is mostly transmitted by female mosquitoes of the Aedes aegypti and Aedes albopictus species, which are widespread in tropical and subtropical areas of the world.  

The symptoms of dengue fever take 3 to 7 days to appear. Some of the typical dengue symptoms include headache, nausea, rash, swollen glands, body aches, muscular pains, and vomiting. Severe dengue is more likely to occur in elderly persons with underlying medical issues. The ELISA test for dengue NS1 antigen is performed: 
 

• to quickly identify dengue virus infection. 
• When the dengue virus infection is being treated initially. 
• To differentiate between flaviviruses and fever. 
   

Why Does One Need a Dengue NS1 Antigen? 

The Dengue NS1 Antigen test is used to identify dengue virus infection and initiate treatment operations. In addition to the existing antibody test, the dengue-antigen-NS1 test can be employed. It aids in the differential diagnosis of flaviviruses. If you reside in or recently returned from a region where dengue fever is prevalent and exhibits symptoms, you might require this test. The following symptoms may appear four to seven days after being bitten by an infected mosquito: 
 

• An unexpectedly high fever (104°F or greater) 
• Inflamed glands 
• Scratches on the face 
• aching behind the eyes or a severe headache 
• aching muscles and joints 
• Vomiting and nauseous 
• Fatigue 
• Intense stomach discomfort 
• Bleeding in gums 
• Bleeding nose 
• Restlessness 
• Breathing trouble 
• Blood in the stools or urine

Preparation and Procedure of Dengue NS1 Antigen Test 

The test requires very little preparation. This test is painless and non-invasive, which means there is no surgery involved. It is a basic serum test administered by venipuncture. However, it is always a good idea to inform the doctor about the drugs the patient is taking. There is no contamination in the test. As a result, using haemolytic, lipemic, icteric, or bacterially contaminated samples might have negative consequences. 

Usually, during the first five days following the beginning of symptoms, this test is carried out early in the course of the illness. This is because NS 1 antigen can be present for up to 5-7 days after the initial day of dengue infection. After then, it starts to leave the body, which might mean that the results are falsely negative. 
 

• A sample of blood is drawn from the arm.  
• The vein beneath the arm’s top portion may be seen plainly since the arm is looped around a belt. The phlebotomist uses Dengue NS1 Antigen Test an alcohol pad to clean the area after the vein is seen.  
• In front of the patient, the needle syringe is unwrapped, and the tube attached to the needle is used to collect blood.  
• The belt is relaxed once the blood has been drawn to allow the blood to return to the body naturally. 
• After the region has been suitably massaged and wiped with a cotton ball, the patient is asked to keep his arm folded in front of him for a few minutes.  
• Following collection, the research laboratory receives the blood sample for analysis. 
   

Interpretation of Dengue NS1 Antigen Test 

Positive results of more than 1.1 

If the test is positive, you have likely contracted the dengue virus. To confirm dengue infection, dengue IgG & IgM serology tests should be run on follow-up samples 5-7 days following the beginning of a fever.  

Negative Result: Less than 0.9 

No NS1 antigen for dengue is present. If the test yields a negative result, you may not be sick or you may have been tested too soon for the virus to manifest. Within 7 to 14 days, to assess if they may have recently been exposed to dengue, those with negative NS1 results should also be analysed for IgG and IgM serology. 

The results should be utilized in combination with the exposure history and clinical presentation. False-positive non-structural protein 1 (NS1) findings are rare but can happen in people who are actively infected with other flaviviruses like West Nile virus or yellow fever virus. If the sample was taken more than 7 days after the commencement of the symptoms, negative findings for the NS1 antigen may be obtained.  

In these situations, serologic testing for the existence of IgM and IgG antibodies to the dengue virus is advised. Ask your doctor whether you need to be retested if you believe you may have been exposed to the dengue virus or if you are experiencing signs of illness.