Monkeypox Virus IgG/IgM Rapid Test
Monkeypox is used to be a viral zoonosis with symptoms very similar to those in smallpox patients, caused by by infection with Monkeypox virus. It is an enveloped double-stranded DNA virus that belongs to the Orthopoxvirus genus of the Poxviridae family. Human monkeypox was first identified in humans in 1970 in the Democratic Republic of the Congo in a 9-year-old boy in a region where smallpox had been eliminated in 1968. Since then, most cases have been reported from rural, rainforest regions of the Congo Basin, particularly in the Democratic Republic of the Congo and human cases have increasingly been reported from across Central and West Africa. In humans, the symptoms of monkeypox are similar to but milder than the symptoms of smallpox. Monkeypox begins with fever, headache, muscle aches, and exhaustion. The main difference between symptoms of smallpox and monkeypox is that monkeypox causes lymph nodes to swell (lymphadenopathy) while smallpox does not. The incubation period (time from infection to symptoms) for monkeypox is usually 7−14 days but can range from 5−21 days.
The Monkeypox virus IgG/IgM Rapid Test is a rapid test that utilizes a combination of Monkeypox antigen coated colored particles for the detection of IgG and IgM Monkeypox antibodies in human whole blood, serum, or plasma.
The Monkeypox virus IgG/IgM Rapid Test is a qualitative membrane-based immunoassay for the detection of Monkeypox antibodies in whole blood, serum, or plasma. This test consists of two components, an IgG component and an IgM component. In the IgG component, anti-human IgG is coated in test line region G of the test. During testing, the specimen reacts with Monkeypox antigen-coated particles in the test strip. The mixture then migrates upward on the membrane chromatographically by capillary action and reacts with the anti-human IgG in test line region G. If the specimen contains IgG antibodies to Monkeypox, a colored line will appear in test line region G. In the IgM component, anti-ligand is coated in test line region M of the test. During testing, the specimen reacts with ligand anti-human IgM. Monkeypox IgM antibodies, if present in the specimen, reacts with the ligand anti-human IgM and the Monkeypox antigen-coated particles in the test strip, and this complex is captured by the anti-ligand, forming a colored line in test line region M.
Therefore, if the specimen contains Monkeypox IgG antibodies, a colored line will appear in test line region G. If the specimen contains Monkeypox IgM antibodies, a colored line will appear in test line region M. If the specimen does not contain Monkeypox antibodies, no colored line will appear in either of the test line regions, indicating a negative result. Appearance of a colored band at the control region serves as a procedural control, indicating that the proper volume of specimen has been added and membrane wicking has occurred.
SPECIMEN COLLECTION AND STORAGE
- The Monkeypox virus IgG/IgM Rapid Test is intended for use with human whole blood, serum or plasma specimens only.
- Only clear, non-hemolyzed specimens are recommended for use with this test. Serum or plasma should be separated as soon as possible to avoid hemolysis.
- Perform testing immediately after specimen collection. Do not leave specimens at room temperature for prolonged periods. Serum and plasma specimens may be stored at 2-8°C for up to 3 days. For long term storage, specimens should be kept below -20°C. Whole blood collected by venipuncture should be stored at 2-8°C if the test is to be run within 2 days of collection. Do not freeze whole blood specimens. Whole blood collected by fingerstick should be tested immediately.
- Containers containing anticoagulants such as EDTA, citrate, or heparin should be used for whole blood storage.
- Bring specimens to room temperature prior to testing. Frozen specimens must be completely thawed and mixed well prior to testing. Avoid repeated freezing and thawing of specimens.
- If specimens are to be shipped, pack them in compliance with all applicable regulations for transportation of etiological agents.
- Icteric, lipemic, hemolysed, heat treated and contaminated sera may cause erroneous results.
INTERPRETATION OF RESULTS
IgG Positive:* The colored line in the control line region (C) appears, and a colored line appears in test line region G The result is positive for Monkeypox virus specific-IgG and is probably indicative of secondary Monkeypox infection.
IgM Positive:* The colored line in the control line region (C) appears, and a colored line appears in test line region M. The result is positive for Monkeypox virus specific-IgM antibodies and is indicative of primary Monkeypox infection.
IgG and IgM Positive:* The colored line in the control line region (C) appears, and two colored lines should appear in test line regions G and M. The color intensities of the lines do not have to match. The result is positive for IgG & IgM antibodies and is indicative of secondary Monkeypox infection.
*NOTE: The intensity of the color in the test line region(s) (G and/or M) will vary depending on the concentration of Monkeypox antibodies in the specimen. Therefore, any shade of color in the test line region(s) (G and/or M) should be considered positive.
Negative: Only one colored band appears, in the control region (C). No line appears in test line regions G or M.
INVALID: No Control line (C) appears. Insufficient buffer volume or incorrect procedural techniques are the most likely reasons for control line failure. Review the procedure and repeat the procedure with a new test device. If the problem persists, discontinue using the test kit immediately and contact your local distributor.
The specimens were correctly identified >99% of the time.
LIMITATIONS OF THE TEST
- The Monkeypox virus IgG/IgM Rapid Test is for in vitro diagnostic use only. The test should be used for the detection of Monkeypox antibodies in whole blood, serum or plasma specimens only. Neither the quantitative value nor the rate of increase in Monkeypox antibody concentration can be determined by this qualitative test.
- The Monkeypox virus IgG/IgM Rapid Test will only indicate the presence of Monkeypox antibodies in the specimen and should not be used as the sole criteria for the diagnosis of Monkeypox.
- The continued presence or absence of antibodies cannot be used to determine the success or failure of therapy.
- Results from immunosuppressed patients should be interpreted with caution.
- As with all diagnostic tests, all results must be interpreted together with other clinical information available to the physician.
- If the test result is negative and clinical symptoms persist, additional testing using other clinical methods is recommended. A negative result does not at any time preclude the possibility of Monkeypox infection.