Introduction:
Dengue fever is a viral illness that spreads by the bite of an infected mosquito. It is a severe and potentially fatal illness that affects millions of people worldwide. Early diagnosis and treatment of dengue fever are crucial for a better prognosis. One of the diagnostic tools used for the early detection of dengue fever is the Dengue Card Test. In this blog post, we will discuss the principle of the Dengue Card Test, its requirements, specimen, procedure, observation, and results in detail.
Principle of Dengue Card Test:
The Dengue Card Test is a rapid diagnostic test that detects the presence of dengue virus-specific antibodies in human serum or plasma. The test is based on the principle of immunochromatography, where the dengue virus-specific antibodies in the specimen react with the antigen-coated on the test strip, producing a visible band.
What is dengue card test?
Diagnose Dengue card is a rapid solid phase Immuno-chromatographic test for the qualitative differential detection of IgM and IgG antibodies to dengue virus in Human serum /Plasma.
Methodology:
Semi-Quantitative Enzyme-Linked Immunosorbent Assay.
Requirements for Dengue Card Test:
The following are the requirements for the Dengue Card Test:
- Dengue Card Test kit
- Specimen collection tubes
- Sterile lancets for blood collection
- Alcohol swabs for disinfection
- Timer or stopwatch
- Disposable gloves
Specimen for Dengue Card Test:
The Dengue Card Test requires a small amount of human serum or plasma. Separate serum from cells ASAP or within 2 hours of collection. The specimen can be collected using a sterile lancet by pricking the finger or by venipuncture. The specimen should be collected in a sterile collection tube and transported to the laboratory as soon as possible.
Unacceptable Conditions:
Bacterially contaminated, heat-inactivated, hemolyzed, icteric, lipemic, or turbid specimens.
Stability
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Procedure of Dengue Card Test:
The following is the procedure for the Dengue Card Test:
- Clean the finger or venipuncture site with an alcohol swab.
- Collect the specimen using a sterile lancet or venipuncture.
- Transfer the specimen to a sterile collection tube.
- Open the Dengue Card Test kit and remove the test strip.
- Place the test strip on a clean and dry surface.
- Add a few drops of the specimen to the sample well on the test strip.
- Set the timer for the recommended time.
- Read the results within the recommended time.
Observation of Dengue Card Test:
The Dengue Card Test results should be observed within the recommended time. The test has a control line and a test line. A visible control line indicates the validity of the test, and a visible test line indicates the presence of dengue virus-specific antibodies in the specimen.
Result of Dengue Card Test:
The Dengue Card Test results are interpreted as positive or negative. A positive test result indicates the presence of dengue virus-specific antibodies in the specimen, and a negative test result indicates the absence of dengue virus-specific antibodies in the specimen.
Conclusion:
The Dengue Card Test is a rapid diagnostic test that detects the presence of dengue virus-specific antibodies in human serum or plasma. The test is based on the principle of immunochromatography and is easy to perform. Early diagnosis and treatment of dengue fever are crucial for a better prognosis. The Dengue Card Test can be used as a diagnostic tool for the early detection of dengue fever.
What are the 3 tests for dengue?
There are several tests available for the diagnosis of dengue fever, but the three most commonly used tests are:
- Dengue NS1 Antigen Test: This test detects the presence of NS1 antigen, a protein produced by the dengue virus, in the blood of the infected person. This test is usually performed in the early phase of the infection and can provide rapid results within a few hours.
- Dengue Antibody Test: This test detects the presence of dengue-specific antibodies, IgM and IgG, in the blood of the infected person. This test is usually performed in the later stages of the infection and can help to confirm the diagnosis of dengue fever.
- Dengue Polymerase Chain Reaction (PCR) Test: This test detects the genetic material of the dengue virus in the blood of the infected person. This test is usually performed in the early phase of the infection and can provide rapid and accurate results. However, it requires specialized laboratory equipment and technical expertise.
What is the normal range of dengue card test?
2.85 IV or greater: Positive – IgG antibody to dengue fever virus detected, which may indicate a current or past infection. 1.64 IV or less: Negative – No significant level of detectable dengue fever virus IgM antibody. 1.65-2.84 IV: Equivocal – Questionable presence of antibodies.
What is NS1 vs IgG in dengue?
NS1 and IgM is secreted into the blood during dengue infection and are detectable within 3-4 days of illness. Therefore this test helps in early diagnosis and treatment of dengue infection. IgG antibodies appear after 14th day of infection and persist for life.
