Appendix A: Defining samples/materials and test results
Samples and Materials
The presence of Alphainfluenzavirus influenzae H5N1 (avian influenza A[H5N1]) in samples or other materials contributes to the determination of applicable regulatory, reporting, and containment requirements.
Table A defines the terms used throughout the Biosafety Advisory that describe whether samples and other materials may contain avian influenza A(H5N1), along with examples. This information helps to clarify and determine what samples and materials are subject to the outlined recommendations and requirements.
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Description |
Samples/materials |
Examples |
|---|---|---|
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Does not contain (Synonym: Highly unlikely to contain) Known to be free of viable avian influenza A(H5N1) or very high likelihood that the material does not contain viable avian influenza A(H5N1). |
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May contain (but unlikely to contain) (Synonym: Not suspected to contain) Reasonable belief that the material does not contain viable avian influenza A(H5N1) but, due to specific circumstances, its presence cannot be ruled out. |
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Contains (Synonyms: Known to contain, highly likely to contain) Known to contain viable avian influenza A(H5N1) or a high likelihood that the material will contain viable avian influenza A(H5N1). Contains also includes materials that are likely or suspected to contain, which is the reasonable belief that the material can or will contain viable avian influenza A(H5N1) due to specific circumstances. |
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Test Results
Once samples and other materials have been tested for avian influenza A(H5N1), the results will fall within one of the following categories. This information helps to clarify and determine what samples and materials are subject to the outlined recommendations and requirements.
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Test Result |
Explanation and interpretation |
|---|---|
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Negative |
A diagnostic test result indicating the complete absence of avian influenza A(H5N1), with no suspicious or inconclusive findings. A negative result signifies that the sample has undergone appropriate testing and can be officially confirmed as free from detectable avian influenza A(H5N1) (e.g., no detectable genetic material, no immunological or serological reaction). |
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Non-Negative (Synonyms: probable, presumptive, suspected, suspicious, inconclusive, and detected) |
A diagnostic test result that cannot be officially reported as either “negative” or “positive.” This may include preliminary screening that suggests the presence of avian influenza A(H5N1) genetic material, samples that react to avian influenza A antigen or antibodies in serological or immunological tests, evidence of gross pathology where the specific strain has not yet been confirmed, or other results that are suspicious or inconclusive (e.g., failed tests, invalid results pending retest, necropsy findings). Further analysis, testing or retesting may be needed to confirm the presence of avian influenza A(H5N1) and to rule out contamination. |
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Positive (Synonyms: confirmed, diagnosed) |
A diagnostic test result that confirms the presence of avian influenza A(H5N1). A positive result indicates that the sample has undergone appropriate testing and can be officially reported as containing detectable avian influenza A(H5N1) (e.g., detectable genetic material, immunological or serological reaction). |