INTENDED USE
This test is a single use, rapid device intended for qualitativedetection of IgM-class antibodies to hepatitis A virus (HAV)in serum, plasma samples. It is intended tobe used in clinical laboratories for diagnosis of acutehepatitis A and management of patients related to infectionwith hepatitis A virus.
SUMMARY
Hepatitis A is a self-limited disease and chronic stage or other complications are rare. Infections occur early in life in areas where sanitation is poor and living conditions are crowded. With improved sanitation and hygiene, infections are delayed and consequently the number of persons susceptible to the disease increases. Because the disease is transmitted through the fecal-oral route in dense populated regions, an outbreak can arise from single contaminated source. The cause of hepatitis A is hepatitis A virus (HAV)-non enveloped positive strand RNA virus with a linear single strand genome, encoding for only one known serotype. HAV has four major, structural polypeptides and it localizes exclusively in the cytoplasm of human hepatocytes. The infection with HAV induces strong immunological response and elevated levels first of IgM and then IgG are detectable within a few days after the onset of the symptoms. The presence of anti–HAV IgM is an important serological marker for early detection and observation of the clinical manifestation of the disease. Increasing levels of anti-HAV IgM are detectable about three weeks after exposure with highest titter after four to six weeks later. Within six months after infection IgM concentration declines to non-detectable levels.
PRINCIPLE OF THE ASSAY
This test employs chromatographic lateral flow device in acassette format. Colloidal gold conjugated recombinantantigens (Au-Ag) corresponding to HAV antigens aredry-immobilized at the end of nitrocellulose membrane strip.Anti-human IgM (anti-μ chain) are bond at the Test Zone (T)and goat anti-mouse IgG antibodies are bond at the ControlZone (C). When the sample is added, it migrates by capillarydiffusion rehydrating the gold conjugate. If present in sample,HAV IgM antibodies will bind with the gold conjugatedantigens forming particles. These particles will continue tomigrate along the strip until the Test Zone (T) where they arecaptured by anti-human IgM (anti-μ chain) generating a visible red line. If there are no HAV IgM antibodies in sample,no red line is formed in the Test Zone (T). The gold conjugatewill continue to migrate alone until it is captured in the ControlZone(C) by the goat anti-mouse IgG antibodies aggregating
in a red line, which indicates the validity of the test.
COMPONENTS
Forty tests/kit
40 HAV IgM colloidal gold rapid test strips, each placed in white plastic cassette and packed in foil pouch, instructions for use, 1×6 ml vial of sample diluents. Materials required but not provided: clock or timer, safety
lancets, alcohol prep-pad, disposable pipettes, specimen collection container, centrifuge, biohazard waste container, sterile gauze or cotton.