This test kit is a single use, a rapid device intended for the qualitative detection of IgM-class antibodies to Hepatitis E virus (HEV) present in the serum or plasma samples. It is intended to be used in the clinical laboratories for diagnosis of acute Hepatitis E and management of patients related to infection with hepatitis E virus.
Hepatitis E virus (HEV) is a single-stranded, non-enveloped RNA virus identified in 1990. Its infection can cause acute or sub-clinical liver diseases similar to hepatitis A. HEV infection is endemic and frequently epidemic in developing countries, it is seen also in developed countries in a sporadic form with or without a history of traveling to the endemic area. The overall case-fatality is 0.5 to 3% and much higher 15 to 25% among pregnant women.
HEV infection is a zoonosis was presented in 1995, then swine HEV and later an avian HEV were identified and sequenced separately in 1997 and 2001. Since then, HEV infection includes anti-HEV; viremia and feces excretion of HEV was seen in a wide variety of animals, like swine, rodents, wild monkeys, cow, goats, deer, dogs and chicken. A direct testimony was reported that the consumption of uncooked dear meat infected with HEV led to acute hepatitis E in human and HEV genome sequences can be detected in pork livers.
With the discovery of epitopes in HEV, HEV serology was further explored and understood. The phenomenon of long-lasting and protective antibodies to HEV was observed that greatly enhance the understanding of the diagnosis, epidemiology, zoonosis-related studies and vaccine development.
PRINCIPLE OF THE ASSAY
This test uses chromatographic lateral flow device in cassette format. Colloidal gold-conjugated recombinants antigens (Au-Ag) correspond to HEV antigens that are dry-immobilized at the end of the nitrocellulose membrane strip. IgM (anti-μ chain) are bonded at the Test Zone (T) and goat-anti-mouse IgM antibodies are bonded at the Control Zone (C). When the sample is added it migrates by the capillary diffusion and rehydrates the gold-conjugate. The HEV IgM antibodies then bind with the gold conjugated antigens forming particles. These particles then continue to migrate along the strip till the Test Zone (T) where they are captured by the anti-human IgM (anti-μ chain) generating a visible red line. If there are no antibodies in the sample, no red line is formed. The gold conjugates continue to migrate alone until it is captured in the Control Zone(C) by the goat-anti-mouse IgM antibodies aggregating in a red line, which indicates the validity of the test.
40 HEV IgM colloidal gold rapid test strips, each placed in a white plastic cassette and is packed in a foil pouch
Instructions for use
5 ml×1 dilution tubes
Materials required but not provided: clock or timer, safety lancets, specimen collection container, alcohol pre-pad, disposable pipettes, centrifuge, biohazard waste container.
Wash your hands properly with soap and warm water. Choose a puncture site on the fingertip, clean the area with alcohol prep-pad. Place a safety lancet on the selected site. Forcefully press the tip of the lance against the fingertip. Wipe away the first drop of blood using sterile gauze or cotton. Now by using a disposable pipette, collect the blood from the puncture site. Alternatively, draw the blood following laboratory procedure for obtaining venous blood.
STORAGE AND STABILITY
This test kit can be stored at room temperature 2 to 30°C, do not freeze. It can be used for about 24 months from the date of manufacture (see the label on pouch). Use it immediately after opening.
PRECAUTIONS AND SAFETY
This test is for In Vitro and for professional use only.
All the waste and sample should be treated as contagious and must be properly disinfected (autoclaving is preferred) before disposing of.
Once opened the pouch, carry out your testing as early as possible, not more than 20 minutes to avoid any moisture absorption. The nitrocellulose membrane can absorb water that can affect the test chromatography performance.
To obtain accurate results, the test results must be read within 15 to 20 minutes. Results read after 20 minutes can lead to incorrect interpretation.
Detection of high rate diluted samples (e.g. more than 100 times), directly dispense 80μL diluted samples for testing.
Make sure that the test is within the indicated validity.
If using an automatic pipette, calibrate it frequently to assure the accuracy of dispensing. Use different disposable pipette tips for each sample in order to avoid Cross-contaminations.
Do not modify the test procedure.
Do not reuse the test cassettes, autoclave before disposal.
An invalid test result should be repeated.
Blood that has been chemically treated, diluted, heated, or modified may give inaccurate results.
Allow the test cassette to reach room temperature, keep for 30 minutes before opening the pouch.
Add one drop approx 10μL serum or plasma sample into the sample dilution tube by using the sample dispenser and mix completely.
Open the pouch and pipette add 100μl of diluted sample into the sample window (S). Avoid dropping the sample into the observation window and do not allow the sample to overflow.
Place the cassette on a horizontal surface and read the results within15-20 minutes.
A positive test line may appear after 20 minutes; this is a false positive result. Do not read the results after 10minutes.
Invalid Results: One red line will always appear next to the Control Zone(C) indicates the validity of the test. If no red line appears, the test is invalid, discard the test and repeat with a new sample and cassette.
Positive Results: One red line next to the Test Zone (T) indicates that IgM antibodies to HEV have been detected.
Negative Results: No red line appears within 10 minutes next to the Test Zone (T) indicates that no IgM antibodies to HEV have been detected.
However, this does not exclude the possibility of infection with HEV.
The positive result obtained with this test kit alone cannot be the final diagnosis of HEV. Any positive result must be interpreted in conjunction with the patient’s clinical history and other laboratory testing. Follow-up and supplementary testing of any positive samples with other analytical systems (e.g. ELISA, WB) is required to confirm the positivity.
Negative results do not exclude the possibility of HEV exposure or infection.
Infection through recent exposure (seroconversion) to HEV may not be detectable.
For positive results, line intensity cannot be used to evaluate the HEV IgM antibody levels. A test should be repeated if giving an invalid result.
After retesting of the initially reactive samples, the test results are negative; these samples should be considered as non-repeatable (false positive) and interpreted as negative.
As with many sensitive rapid diagnostic tests, false positive results can occur due to the several reasons, most of which are related but not limited to the quality of the sample and exposure of the test to the humidity.
For more information and further assistance contact BIONEOVAN.CO. LTD technical support.
This test kit is intended only for testing serum or plasma samples. Do not use it for testing of cadaver samples, urine, saliva, or other body fluids, or pooled (mixed) blood.
This is a qualitative assay and the results cannot be used to measure the antibodies concentrations.