White-nose syndrome diagnostic harmonization
The USGS National Wildlife Health Center, in partnership with the White-nose Syndrome (WNS) National Response Team Diagnostic Working Group, has developed the White-Nose Syndrome Diagnostic Laboratory Network Handbook to harmonize WNS diagnostics.
Why this matters: Wildlife managers rely on consistent and reliable diagnostic information to make management decisions in response to disease outbreaks. Nevertheless, standardized diagnostic methods and criteria for reporting test results for non-reportable wildlife diseases is uncommon. This effort to harmonize white-nose syndrome diagnostics aims to improve consistency in reported results and may be useful as an example of national diagnostic coordination for other wildlife diseases.
Testing for Pseudogymnoascus destructans (Pd), the fungal pathogen that causes white-nose syndrome (WNS) in bats, has expanded rapidly over the past ten years to meet the demands of increased surveillance for this fast-spreading pathogen. During the last decade, quantitative polymerase chain reaction (qPCR) has become the most common method of testing for Pd because of qPCR’s speed, accuracy, and simplicity across a wide range of invasive and noninvasive sample types. Its widespread use by many state, federal, provincial, and academic institutions has inevitably led to variations in methodology and interpretation among laboratories. The progressive geographic spread of fungus and disease has also led to sampling contexts and strategies that differ from those for which the qPCR assay was originally developed and validated. These factors have periodically contributed to inconsistent results from different laboratories, making it difficult to draw conclusions needed for management decisions.
To address these challenges, the WNS National Response Team Diagnostic Working Group launched a project to harmonize testing results and reporting standards across disparate methodologies and laboratories. Beginning in 2019, interlaboratory testing was conducted to better understand how variations in Pd qPCR methodology affect diagnostic consistency and to reassess the assay’s fitness in new testing contexts. This information led to expanded conversations within the Diagnostic Working Group related to best practices in Pd qPCR diagnostic testing, the development of common interpretation language for classifying test results, and the incorporation of that language into an updated WNS case definition.
The White-Nose Syndrome Diagnostic Laboratory Network Handbook resulted from this effort and is intended to help further harmonize Pd qPCR diagnostic testing by establishing recommendations related to voluntary participation in a WNS Diagnostic Laboratory Network, documenting the currently (2022) practiced Pd qPCR methodologies, discussing general best practices for molecular diagnostics and laboratory networks, and elaborating on the epidemiologic and diagnostic basis of the agreed-upon classification language for Pd qPCR results. Through this voluntary, consensus-based approach to diagnostic harmonization, this work aims to improve management agency confidence in reported Pd qPCR results and may be a useful example of national diagnostic coordination for other wildlife diseases.
White-Nose Syndrome
The USGS National Wildlife Health Center, in partnership with the White-nose Syndrome (WNS) National Response Team Diagnostic Working Group, has developed the White-Nose Syndrome Diagnostic Laboratory Network Handbook to harmonize WNS diagnostics.
Why this matters: Wildlife managers rely on consistent and reliable diagnostic information to make management decisions in response to disease outbreaks. Nevertheless, standardized diagnostic methods and criteria for reporting test results for non-reportable wildlife diseases is uncommon. This effort to harmonize white-nose syndrome diagnostics aims to improve consistency in reported results and may be useful as an example of national diagnostic coordination for other wildlife diseases.
Testing for Pseudogymnoascus destructans (Pd), the fungal pathogen that causes white-nose syndrome (WNS) in bats, has expanded rapidly over the past ten years to meet the demands of increased surveillance for this fast-spreading pathogen. During the last decade, quantitative polymerase chain reaction (qPCR) has become the most common method of testing for Pd because of qPCR’s speed, accuracy, and simplicity across a wide range of invasive and noninvasive sample types. Its widespread use by many state, federal, provincial, and academic institutions has inevitably led to variations in methodology and interpretation among laboratories. The progressive geographic spread of fungus and disease has also led to sampling contexts and strategies that differ from those for which the qPCR assay was originally developed and validated. These factors have periodically contributed to inconsistent results from different laboratories, making it difficult to draw conclusions needed for management decisions.
To address these challenges, the WNS National Response Team Diagnostic Working Group launched a project to harmonize testing results and reporting standards across disparate methodologies and laboratories. Beginning in 2019, interlaboratory testing was conducted to better understand how variations in Pd qPCR methodology affect diagnostic consistency and to reassess the assay’s fitness in new testing contexts. This information led to expanded conversations within the Diagnostic Working Group related to best practices in Pd qPCR diagnostic testing, the development of common interpretation language for classifying test results, and the incorporation of that language into an updated WNS case definition.
The White-Nose Syndrome Diagnostic Laboratory Network Handbook resulted from this effort and is intended to help further harmonize Pd qPCR diagnostic testing by establishing recommendations related to voluntary participation in a WNS Diagnostic Laboratory Network, documenting the currently (2022) practiced Pd qPCR methodologies, discussing general best practices for molecular diagnostics and laboratory networks, and elaborating on the epidemiologic and diagnostic basis of the agreed-upon classification language for Pd qPCR results. Through this voluntary, consensus-based approach to diagnostic harmonization, this work aims to improve management agency confidence in reported Pd qPCR results and may be a useful example of national diagnostic coordination for other wildlife diseases.