Dengue is among the most rapidly spreading vector-borne diseases in the world. The key to handling dengue infection is its early recognition and a clear grasp of the clinical problems during the different gradual phases of the disease. This will lead to a rational approach to case management and an excellent clinical outcome- a life saved Dengue infection is a dynamic and systematic disease. There are 3 phases of infection; febrile, critical, and recovery. A Patient in the critical phase may have Plasma leakage leading to Dengue shock syndrome (DSS).
The Dengue NS1 Antigen can be detected from approximately Day 1 to Day 7 of onset of fever. Dengue IgM & IgG Antibodies response to the infection varies as per the host’s immune status.
During a Secondary infection, the Dengue IgG Antibodies level rises quickly, reaching a peak in about two weeks after the onset of symptoms and may persist for years. The IgM antibodies become detectable after about 4-5 days, and their levels are comparatively low.
Therefore Dengue NS1 Antigen test must be performed for the patients exhibiting clinical symptoms of Dengue since NS1 Antigen can be detected from Day 1 of infection.
Rapid tests using a combination of both NS1 Antigen and Antibody (IgM & IgG ) detection to diagnose Dengue bridge the diagnostic challenges posed by the initial period of viremia and the delayed immunological responses. Therefore, if the test result is negative and symptoms persist, a Dengue NS 1 Antigen and IgM & IgG antibody test must be performed to confirm the infection.
The current crop of the Dengue Rapid tests available for diagnosis is a visual test with a user-friendly test procedure. No equipment is required for the same, and they provide test results within 20 minutes.
Samples detected positive in Rapid tests can be confirmed for specific markers, i.e., NS1 Ag, IgM, or IgG on ELISA( Enzyme-linked immunosorbent assay ) as these are more sensitive and specific.
Dengue Diagnosis by Dengue Rapid tests based on Fluorescence immunoassay (FIA)using analyzer is the best alternative to the ELISA with the provision of conducting a single test at a time. They provide test results in 30-40 minutes, and results are presented in terms of Dengue units similar to ELISA.
J Mitra & Co. offers Dengue Rapid Card tests, Dengue Quanti card tests(FIA ), and ELISA range of products to screen and diagnose Dengue infection.
The Dengue Day 1 test is the ideal choice for getting early and fast test results during an outbreak and the first few days of illness since it can detect both current and past infection. In addition, Dengue Quanti cards are the most appropriate test kits for Labs and Hospitals with NABL/NABH accreditation with accurate patient data and documentation results.
As per various studies published, the use of dengue NS1 antigen detection combined with IgM and IgG serology can remarkably increase the sensitivity of acute dengue diagnosis and extend the possible detection window to include very early acute samples. In addition, it enhances the clinical utility of rapid card tests based on the immunochromatography principle for Dengue.
We can conclude that using the Dengue Rapid /ELISA test of good sensitivity and Specificity at the right time is very important to have an early and accurate Dengue diagnosis.