Lab Matters Summer 2022 - Page 23


Public Health Laboratories Respond to Familiar Avian Influenza Threat

by Melissa Warren , senior specialist , Influenza
Highly pathogenic avian influenza ( HPAI ) A ( H5 ) emerged in the United States in early 2022 for the first time since 2016 . 1 The virus was detected first in wild birds and then in commercial poultry in multiple states located in the Atlantic and Mississippi migratory bird flyways .
Based on available epidemiologic and virologic information about these viruses , CDC believes that the risk to the general public ’ s health from current H5N1 bird flu viruses is low , however some people may have job-related or recreational exposures to birds that put them at higher risk of infection .” 3
Getting Reacquainted with HPAI
During the US outbreak of avian influenza in 2015-2016 , over seven million turkeys and 43 million chickens died from disease or were depopulated to control the spread of the virus representing a significant economic loss for the poultry industry . Of the 2015-2016 outbreak , the US Department of Agriculture ( USDA ) Animal and Plant Health Inspection Service ( APHIS ) states “ this outbreak was the largest HPAI outbreak ever recorded in the US and arguably the most significant animal health event in US history .” 2
Avian and swine influenza viruses are important to public health due to the potential introduction of a novel virus to susceptible human populations . The H5 virus recently detected in birds appears to lack ability to cross over to mammalian species and antivirals would likely be effective treatment . Based on these factors the perceived risk is relatively low , but it is not zero and merits further monitoring .
The Public Health Laboratory Response
US Centers for Disease Control and Prevention ( CDC )— public health laboratories may test suspected H5 specimens in parallel on the H5 diagnostics assay and the influenza A / B assays , as opposed to in succession .
Lixia Liu , PhD , MP ( ASCP ), D ( ABMM ), laboratory director and Brian Pope , Virology supervisor from the Indiana Department of Health Laboratory Division recently shared their experience with the current H5 outbreak . Six flocks of sick poultry from southern Indiana were identified by the APHIS National Veterinary Services Laboratory in February . The commercial turkeys were confirmed to be infected with H5N1 by the Animal Disease Diagnostic Laboratory at Purdue University . The State Veterinarian and Board of Animal Health coordinated with state partners , including arranging with the Department of Health ’ s epidemiology and laboratory divisions for human health surveillance .
“ The public health veterinarian did great work and included background [ information ] from 2016 .” Liu said . “ We were prepared as partners . Everyone knows what it takes to respond .”
Pope described the communication as “ early and often ” between state partners and that the laboratory was kept in the loop ready to receive specimens for testing . As of April 1 , the laboratory received four specimens related to the H5 response from symptomatic patients , however all tested positive for influenza A ( H3 ), not H5 . Pope concluded with the reminder to reach out to CDC or other laboratories to learn from those who have been through a similar experience .
Tim Southern , PhD , director of the South Dakota State Public Health Laboratory echoed Pope ’ s sentiments .
“ This is a quintessential One Health program so nothing will replace good communication between the professionals that work in the poultry industry and the human healthcare and public health sectors .” n
1 . CDC . Recent Bird Flu Infections in US Wild Birds and Poultry Pose a Low Risk to the Public . February 14 , 2022 . Available from https :// www . cdc . gov / flu / avianflu / spotlights / 2021-2022 / bird-flu-poses-lowrisk-public . htm .
2 . US Department of Agriculture . Final Report for the 2014-2015 Outbreak of Highly Pathogenic Avian Influenza ( HPAI ) in the United States . Revised August 11 , 2016 . Available from https :// www . aphis . usda . gov / animal _ health / emergency _ management / downloads / hpai / 2015-hpai-final-report . pdf .
3 . CDC . March 7 , 2022 Update : H5N1 Bird Flu Poses Low Risk to the Public . March 7 , 2022 . Available from https :// www . cdc . gov / flu / avianflu / spotlights / 2021-2022 / h5n1-low-risk-public . htm .
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