Span Biotech Ltd.

INTENDED USE

The One Step Dengue NS1 Ag Test is a rapid chromatographic immunoassay for the qualitative detection of dengue virus NS1 antigen in serum or plasma and whole blood to aid in the diagnosis of Dengue viral infection.

SUMMARY

Dengue is transmitted by the bite of an Aedes mosquito infected with any one of the four dengue viruses. It occurs in tropical and sub-tropical areas of the world. Symptoms appear 3—14 days after the infective bite. Dengue fever is a febrile illness that affects infants, young children and adults. Dengue haemorrhagic fever (fever, abdominal pain, vomiting, bleeding) is a potentially lethal complication, affecting mainly children. Early clinical diagnosis and careful clinical management by experienced physicians and nurses increase survival of patients. One step Dengue NS1 Ag Test is a simple, visual qualitative test that detects dengue virus NS1 antigen in human serum or plasma. The test is based on immunochromatography and can give a result within 15 minutes.  

PRINCIPLE OF THE PROCEDURE

The One Step Dengue NS1 Ag Test is a qualitative membrane strip based immunoassay for the detection of dengue virus NS1 antigen in serum or plasma and whole blood. In this test procedure, anti-Dengue NS1 antibody is immobilized in the test line region of the device. After a Serum or plasma or blood specimen is placed in the specimen well, it reacts with anti-Dengue NS1 antibody coated particles that have been applied to the specimen pad. This mixture migrates chromatographically along the length of the test strip and interacts with the immobilized anti-Dengue NS1 antibody. If the specimen contains dengue virus NS1 antigen, a colored line will appear in the test line region indicating a positive result. If the specimen does not contain dengue virus NS1 antigen, a colored line will not appear in this region indicating a negative result. To serve as a procedural control, a colored line will always appear at the control line region indicating that proper volume of specimen has been added and membrane wicking has occurred..

REAGENTS AND MATERIALS SUPPLIED

1.Test cards/ test strips individually foil pouched with a desiccant

2.Sample diluent

3.Package Insert

MATERIALS REQUIRED BUT NOT PROVIDED

1.Timer

2.Centrifuge

3.Specimen Collection Containers

RAGE AND STABILITY

1.Store unused kit at 2 - 30°C.

2.Store test cards/strips at 2 - 30°C and away from direct sunlight. 

WARNINGS AND PRECAUTIONS

1.For professional in vitro diagnostic use only. Do not use after expiration date.

2.Do not eat, drink or smoke in the area where the specimens and kits are handled.

3.Handle all specimens as if they contain infectious agents.

4.Observe established precautions against microbiological hazards throughout all procedures and follow the standard procedures for proper disposal of specimens.

5.Wear protective clothing such as laboratory coats, disposable gloves and eye protection when specimens are assayed.

6.Follow standard biosafety guidelines for handling and disposal of potential y infective material.

7.Humidity and temperature can adversely affect results

SAMPLE COLLECTION AND PREPARATION

1.The One Step Dengue NS1 Ag Test can be performed used on Serum or plasma and whole blood.

2.To collect whole blood, serum or plasma specimens following regular clinical laboratory procedures.

3.Separate serum or plasma from blood as soon as possible to avoid hemolysis. Use only clear non-hemolyzed specimens.

4.Testing should be performed immediately after specimen collection. Do not leave the specimens at room temperature for prolonged periods. Serum and plasma specimens may be stored at 2-8℃ for up to 3 days. For long term storage, specimens should be kept below -20℃.

5.Bring specimens to room temperature prior to testing. Frozen specimens must be completely thawed and mixed well prior to testing. Specimens should not be frozen and thawed repeatedly.

ASSAY PROCEDURE

Allow the test, specimen and/or controls to reach room temperature 15-30℃ (59-86℉) prior to testing.

1. Bring the pouch to room temperature before opening it. Remove the test device from the sealed pouch and use it as soon as possible.

2. Place the test device on a clean and level surface.

3. For serum or plasma or whole blood specimen: Hold the dropper vertically and transfer 3 drops of serum or plasma (approximately 100μl) to the specimen well(S) of the test device, then start the timer. See illustration below.

4. Wait for the colored line(s) to appear. Read results at 15 minutes. Do not interpret the result after 20 minutes 

NOTE:  Applying sufficient amount of specimen is essential for a valid test result. If migration (the wetting of membrane) is not observed in the test window after one minute, add one more drop of specimen (serum or plasma) to the specimen well.

READING THE TEST RESULTS

Positive:  Two lines appear. One line should always appear in the control line region(C), and another one apparent colored line should appear in the test line region.

Negative: One colored line appears in the control region(C).No apparent colored line appear in the test line region.

Invalid:    Control line fails to appear. Insufficient specimen volume or incorrect procedural techniques are the most likely reasons for control line failure. Review the procedure and repeat the test with a new test device. If the problem persists, discontinue using the test kit immediately and contact your local distributor.

PERFORMANCE CHARACTERISTICS

Specificity and Sensitivity

1.The One Step Dengue NS1 Ag Test has been evaluated with specimens obtained from a population of symptomatic individuals who presented for examination. The result shows that the sensitivity of the One Step Dengue NS1 Ag Test is 90.0% and the specificity is 99.6% compared to actual results obtained.

2.The analytical sensitivity of the Dengue NS1 Ag Rapid Test is 3ug/ml.

LIMITATIONS OF THE TEST

1.The One Step Dengue NS1 Ag Test is for in vitro diagnostic use only. The test should be used for the detection of dengue virus NS1 antigen in Serum or plasma and blood specimens only. Neither the quantitative value nor the rate of increase in dengue virus NS1 antigen can be determined by this qualitative test.

2.The One Step Dengue NS1 Ag Test will only indicate the presence of dengue virus NS1 antigen in the specimen and should not be used as the sole criteria for the diagnosis of dengue virus infection.

3.As with all diagnostic tests, all results must be interpreted together with other clinical information available to the physician.

4.If the test result is negative and clinical symptoms persist, additional testing using other clinical methods is recommended. A negative result does not at any time preclude the possibility of dengue virus infection