Test Principle

Explanation of the Test
LABit Dengue NS1 Ag device is an immuno-chromatographic assay used for the rapid detection of dengue virus NS1 antigen in human blood. Dengue-specific antibodies complexed with gold conjugate are placed in the conjugate pad in the test region, while anti-dengue NS1 antibodies are immobilized on the membrane. When a dengue antigen positive specimen is loaded into the sample injection point, the liquid sample migrates to the test region via lateral flow movement then antigen is captured by immobilized anti-dengue NS1 antibodies on the membrane. The antigen reacts with dengue-specific antibodies complexed with gold conjugate to make a visible band in the test line.

Biomedical Background

The Disease
Dengue is caused by a virus transmitted by Aedes aegypti and A. albopictus mosquitoes but usually the former is the main vector of the disease. Four known viral serotypes are known to cause dengue infection these are: dengue virus 1 (DENV-1), dengue virus 2 (DENV 2), dengue virus 3 (DENV-3), and dengue virus 4 (DENV-4). Some reports declared that a person can be infected concurrently by more than one viral serotypes. There are three forms of dengue infection: dengue fever (DF), dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) and each of them has its different implications.

The Course of Dengue Illness
Source: WHO Dengue: Guidelines for Diagnosis Treatment, Prevention and Control

The Substance it Detects
NS1 (stands for non-structural protein 1) is one of the proteins encoded by the genome of dengue virus. NS1 in the biological samples suggests dengue infection and it is the key to the early detection of the disease. Antibodies IgG/IgM titers are very low during the early acute phase of dengue infection, however, NS1 level is high. Its timely recognition can subsequently result to good clinical management of the illness.

Dengue Virus Serology

Dengue Methods of Detection
Source: WHO Dengue: Guidelines for Diagnosis Treatment, Prevention and Control

Product Technical Specification

LABit Dengue Test
Reading Time 15-20 mins
Specimen Whole blood, plasma, serum
Volume of Sample 100 μL
Storage Temperature 2-30C (35.6~86F)
Format Test Device
Limits of Detection 5.8 ng/mL
Shelf Life 24 months after date of manufacture
Sensitivity 97.16%
Specificity 100%
Accuracy 98%

Limitations of the Test
LABit Dengue Test is designed for primary screening test of dengue virus NS1 antigen.

References

  1. Chakraborty, T. (2008) Deadly Diseases and Epidemics: Dengue Fever and Other Hemorrhagic Viruses. New York, USA: Infobase Publishing.
  2. Edillo,F.E., Halasa,Y.A., Largo, F.M, Erasmo, J.N.V., Amoin, N.B, Alera, M.T.P,…Shepard, D.S. (2015) Economic Cost and Burden of Dengue in the Philippines (Abstract) Am J Trop Med Hyg. 2015 Feb 4; 92(2): 360–366. doi: 10.4269/ajtmh.14-0139
  3. World Health Organization. (2009) Dengue: Guidelines for Diagnosis Treatment, Prevention and Control (New Edition). © 2016 by Philab Industries Inc.