Rotavirus is the primary causative agent for acute gastroenteritis, especially in children of less than 2 years. It was discovered in 1973 and its association with infantile gastroenteritis represented an advanced study of gastroenteritis that it is not caused by acute bacterial infection. Rotavirus is transmitted by oral-fecal contact with an incubation period of 1 to 3 days.
Adenovirus is the second most common cause of viral gastroenteritis in children (10 to 15%). This virus may also cause respiratory diseases and, depending on the serotype, it also causes diarrhea, cystitis, conjunctivitis, etc. At least 47 serotypes of adenovirus have been described till now, all sharing a common hexon antigen. Serotypes 40 and 41 are the ones associated with gastroenteritis, whose main symptom is diarrhea that may last between 9 to 12 days associated with the temperature and vomits.
SUMMARY AND PRINCIPLE OF THE TEST
This test kit and uses a new homogenous immunochromatographic system with gold particulates. It is ready to use test and only needs a fecal sample dilution with the supplied ready to use dilution buffer. The test is specific as it uses the monoclonal antibody conjugated with gold particulates and is directed against the specific human genus-specific Rotavirus antigen or Adenovirus antigens. The immunochromatographic stick is coated with a monoclonal immunoreagent that is specific for genus-specific Adenovirus hexon antigens or rotavirus VP6 antigen. Liquid sample and gold conjugate both migrate by the capillary action and reaches the first specific anti-Adenovirus monoclonal reagent. If Adenovirus is present in the sample, it is blocked and immunoreactions appear as a red-pink line. As sample still migrates, it reaches the second non specific anti-mouse IgG that gives rise to a second red-pink line. This rear line indicates that the chromatography has been developed without any hindrance. It also appears with negative samples.
REAGENTS AND MATERIALS
Extraction Buffer 15ml
Instruction for use 1
PRECAUTION FOR USERS
It is used for in-vitro diagnostic only.
Handle all the specimens carefully as if they contain infectious agents. When the assay procedure is completed, dispose of the specimens carefully after autoclaving for at least one hour. Alternatively, treat it with a 0.5 or 1% solution of sodium hypochlorite for one hour before disposing of.
While testing wear laboratory coat and disposable gloves.
Avoid eating, drinking or smoking in the areas where specimens and kit reagents are being handled.
Avoid any contact between hands and eyes or nose during the specimen collection and testing.
Stool samples must be taken as soon as the symptoms appear, viral particles decrease in number after one week onset of symptom, making the diagnosis difficult. The samples can be stored in the refrigerator for 1 to 2 days and for longer storage they must be kept frozen at -20ºC. When frozen the sample should be totally thawed, and brought to room temperature and homogenized before testing.
STORAGE OF TEST KIT
Rota/Adeno Rapid Test Strip can be stored at any room temperature between 4 to 30°C. Do not freeze. The stability of the kit under these storage conditions is of 24 months. Use the reagents as soon as possible after opening the kit.
Allow all reagents to reach room temperature before use.
Add 0.5 to 1ml of extraction buffer in a properly marked testing tube.
Add a sample portion of approximately 5 to 6 mm size (25-100mg), with a swab, a wooden applicator or a bacteriology loop. Squeeze the applicator to the tube wall. For liquid or semi-solid stools add 100 micro liters of specimen using an appropriate pipette.
Shake it vigorously in order to re-suspend it into the buffer. If needed Vortex shake for 15 seconds.
Dip the reaction strip into the test tube with an arrow pointing to the bottom.
Incubate the test at room temperature and read the test in 5 to 15 minutes.
INTERPRETATION OF RESULTS
Negative: One pink line appears in the control line, indicating the test has been carried out correctly and there will be no line in test region.
Positive: In addition to a pink colored control line, an upper test line will also appear, for rotavirus positive.
Invalid: Absence of color in both regions is an indication of procedural error and/or that the test reagent has deteriorated. It is recommended repeat the test by using a new strip.
LIMITATIONS OF THE ASSAY
The test should be used only for the detection of rotavirus and adenovirus antigen in fecal samples.
This test is qualitative and not used for quantitative interpretation with respect to the intensity of the positive line when reporting the result.
More than 200 samples were evaluated to assure the correct performance of the test. The correlation of the results with other techniques (ELISA) was excellent. However, interferences in the performance of the tests should not be excluded.
No cross-reactions with other viruses or substances were observed. A negative result does not totally exclude the possibility of rotavirus infection. The significance of the results must be evaluated in relation to the patient’s clinical symptoms.
Specificity: 97 % (in comparison with an ELISA test)
Sensitivity: 98 % (in comparison with an ELISA test)
Inter-series and intra-series accuracy: 100 %
Interference: Cross reactivity has been evaluated and found to be negative as compared to the positive specimens of Cryptosporidium parvum, rotavirus.