INTENDED USE
The HEV IgG/IgM Rapid Test Cassette by Novala Biotech is a lateral flow immunoassay intended for the qualitative detection of antibodies (IgG and IgM) to Hepatitis E virus (HEV) in human whole blood, serum, or plasma. It provides a diagnostic aid for detecting HEV infections.
SUMMARY
Hepatitis E is an acute liver disease caused by the Hepatitis E virus (HEV), primarily transmitted via the fecal-oral route. While generally self-limiting, it can have severe implications for pregnant women. The disease’s prevalence is linked to socioeconomic conditions, and its spread is more common in areas with inadequate sanitation. Seroepidemiological studies suggest anti-HEV antibody prevalence ranges from 15% to 100% in different regions.
PRINCIPLE OF THE ASSAY
The HEV IgG/IgM Rapid Test Cassette is a membrane-based immunoassay that detects antibodies (IgG and IgM) specific to HEV in whole blood, serum, or plasma. The test contains:
- Conjugate Pad: Contains HEV recombinant antigens conjugated with colloidal gold.
- Nitrocellulose Membrane: Pre-coated with Mouse anti-Human IgM and IgG antibodies on the test line, and Goat anti-HEV antibody on the control line.
When the sample is applied to the cassette, it migrates through capillary action. If the sample contains HEV IgG or IgM antibodies, they form an immunocomplex with the HEV conjugates, resulting in a burgundy line on the respective IgM and/or IgG test lines, indicating HEV IgG or IgM positivity.
- IgM Line: Indicates a fresh HEV infection.
- IgG Line: Indicates past or repeat HEV infection.
Absence of test lines indicates a negative result, while a procedural control line (C) should always appear to confirm the test’s validity.
WARNINGS AND PRECAUTIONS
- For professional use only.
- In vitro diagnostic use only.
- Do not use the test cassette beyond its expiration date.
- Read the entire instruction before performing the test.
- Keep the test cassette in its sealed pouch until use.
- All samples should be treated as potentially infectious.
- Dispose of used test cassettes according to local regulations.
COMPOSITION
- Test Cassette: Contains membrane strips with Mouse anti-Human IgG, Mouse anti-Human IgM, and Goat anti-HEV polyclonal antibodies.
- Buffer Solution
- Dropper
- Information for Use
Materials Required but Not Provided:
- Timer
- Specimen collection materials
STORAGE AND STABILITY
- Store the test kit in the sealed pouch at 4-30°C (40-86°F). The kit is stable until the expiration date.
- Use the test cassette within one hour after opening the pouch to avoid deterioration due to prolonged exposure to humidity or heat.
- Do not freeze the kit or expose it to direct sunlight.
SPECIMEN COLLECTION AND STORAGE
- The test can be performed using whole blood, serum, or plasma.
- For whole blood, serum, or plasma collection, follow clinical laboratory procedures.
- Store serum or plasma at 2-8°C for up to 7 days. For longer storage, freeze at -20°C. Do not freeze whole blood.
- Avoid hemolyzed, lipemic, or grossly contaminated samples to ensure accurate results.
TEST PROCEDURE
- Preparation: Allow the test device and samples to reach room temperature (15-30°C or 59-86°F) before starting the test.
- Test Setup:
- Open the sealed pouch and remove the test cassette. Place it on a clean, level surface.
- Hold the dropper vertically, and add 1 drop (approximately 10µL) of specimen into the sample well (S) on the test cassette.
- Add 2 drops (approximately 70µL) of buffer to the same well.
- Start Timer: Begin timing after adding the buffer.
- Result Interpretation: Wait for the colored lines to appear. Read the results at 15 minutes. Do not interpret results after 20 minutes.
RESULT INTERPRETATION
- Positive: Control line (C) and one or both test lines (IgM or IgG) appear:
- IgM Positive: Indicates a fresh HEV infection.
- IgG Positive: Indicates past or repeat HEV infection.
- Negative: Only the control line (C) appears, indicating no detectable HEV antibodies.
- Invalid: No control line (C) appears. Repeat the test with a new cassette.
QUALITY CONTROL
- The internal control line (C) verifies that sufficient specimen volume was added, and membrane wicking occurred.
- Positive and negative controls are recommended for use as per good laboratory practice to verify the test’s performance.
LIMITATIONS
- This test is a qualitative assay and does not quantify antibody concentration.
- Results should be interpreted with patient history and other diagnostic tools.
- Negative results may indicate an absence or undetectable levels of HEV antibodies.
- Certain conditions, such as early infection, may result in false-negative results.
PERFORMANCE CHARACTERISTICS
- Clinical Sensitivity: 98.32% for IgG and 98.33% for IgM.
- Clinical Specificity: 98.80% for IgG and 98.95% for IgM.
- Accuracy: 98.63% for IgG and 98.73% for IgM.
Data based on clinical evaluations with 1,025 specimens.
CROSS-REACTIVITY AND INTERFERENCE
The HEV IgG/IgM Rapid Test showed no cross-reactivity with other infectious diseases (e.g., HIV, HAV, HBsAg, HCV, HTLV, CMV, and TP) or endogenous substances (e.g., lipids, haemoglobin, bilirubin) spiked into HEV positive and negative samples.
REPRODUCIBILITY
- Reproducibility studies were conducted at three independent laboratories using 60 clinical samples (negative, borderline positive, and positive). The intra-assay agreement was 100%, with no variation across different testing sites.
This HEV IgG/IgM Rapid Test by Novala Biotech provides reliable, quick, and effective results for diagnosing Hepatitis E virus, making it ideal for clinical and laboratory use.
BIBLIOGRAPHY
- Li, Shao-Wei et al., “The development of a recombinant hepatitis E vaccine HEV 239.” Human Vaccines & Immunotherapeutics.
- Subrat, Kumar, “Hepatitis E virus: the current scenario.” International Journal of Infectious Disease.
- Hoofnagle, J.H. et al., “Hepatitis E,” New England Journal of Medicine.
Above information are for Professional and In Vitro Diagnostic Use Only