Interpretation guide: SINGLE BAND tests: Difference between revisions
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'''Less likely but possible alternatives:''' | '''Less likely but possible alternatives:''' | ||
*A faint band was present but not seen by observer | *A faint band was present but not seen by observer | ||
*The species is present but not detected due to low parasite concentration | *The species is present but not detected due to low parasite concentration | ||
*The species is present is but not detected for technical reasons [ [[Practical reasons for poor RDT performance]] ] | *The species is present is but not detected for technical reasons [ [[Practical reasons for poor RDT performance]] ] | ||
*The species is present, but there is gene deletion of the target antigen (HRP2 tests) [ [[HRP2 gene deletion]] ] | *The species is present, but there is gene deletion of the target antigen (HRP2 tests) [ [[HRP2 gene deletion]] ] | ||
Revision as of 15:24, 26 September 2024
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| RESULT PATTERN 1
|
No band appears in the control area (black arrow)
Irrespective of whether any other bands are present, this is always an invalid test: do not interpret. Report as failed test
Action:
- Repeat the test
- Consider the reasons for [ test failure ]
| RESULT PATTERN 2 |
The test has valid control line (black arrow) and an additional band in the species-specific area (red arrow)
Most likely interpretation: The species detected by the test is present and is the only malaria species infecting the individual
Less likely but possible interpretations:
- There is a dual-species infection (a second species cannot be detected by single band kits) [ Co-infection with two species ]
- The patient recently received successful treatment, but the antigen has not yet cleared [ Clearance of parasite antigens from blood ]
- The "specific band" is a false positive result (infrequent but observed) [ see here ]
| RESULT PATTERN 3 |
The test has valid control line (black arrow) but there is no band in the species-specific area (red arrow)
Most likely interpretation: the species detected by the test is not present
Less likely but possible alternatives:
- A faint band was present but not seen by observer
- The species is present but not detected due to low parasite concentration
- The species is present is but not detected for technical reasons [ Practical reasons for poor RDT performance ]
- The species is present, but there is gene deletion of the target antigen (HRP2 tests) [ HRP2 gene deletion ]
- The species is present but exceeds test capacity due to very high parasite Pyrome effect (mainly HRP2 tests) [ Prozone effect ]