Environmental samples test negative for avian influenza virus H5N1 four months after mass mortality at a seabird colony

Furness, R. W., Gear, S. C., Camphuysen, K. C. J., Tyler, G., de Silva, D., Warren, C. J., James, J., Reid, S. M. and Banyard, A. C. (2023) Environmental samples test negative for avian influenza virus H5N1 four months after mass mortality at a seabird colony. Pathogens, 12(4), 584. (doi: 10.3390/pathogens12040584) (PMID:37111470) (PMCID:PMC10144497)

Abstract

High pathogenicity avian influenza (HPAI) profoundly impacted several seabird populations during the summers of 2021 and 2022. Infection spread rapidly across colonies, causing unprecedented mortality. At Foula, Shetland, 1500 breeding adult great skuas Stercorarius skua, totalling about two tonnes of decomposing virus-laden material, died at the colony in May−July 2022. Carcasses were left where they died as Government policy was not to remove dead birds. The factors influencing risk of further spread of infection are uncertain, but evidence suggests that HPAI can persist in water for many months in cool conditions and may be a major transmission factor for birds living in wetlands. We investigated risk of further spread of infection from water samples collected from under 45 decomposing carcasses and in three freshwater lochs/streams by sampling water in October 2022, by which time the great skua carcasses had rotted to bones, skin, and feathers. No viral genetic material was detected four months after the mortality, suggesting a low risk of seabird infection from the local environment when the seabirds would return the next breeding season. These findings, although based on a relatively small number of water samples, suggest that the high rainfall typical at Shetland probably washed away the virus from the decomposing carcasses. However, limitations to our study need to be taken on board in the design of environmental monitoring at seabird colonies during and immediately after future outbreaks of HPAI.

• Item Type: Articles
• Additional Information: A.C.B., J.J., S.M.R., C.J.W., and D.d.S. were part funded by the UK Department for Environment, Food, and Rural Affairs (Defra) and the devolved Scottish and Welsh governments under grants SV3400, SV3032, and SE2213. A.C.B., J.J., and D.d.S. were also part funded by the BBSRC/Defra funded research initiative “FluMAP” (BB/X006204/1).
• Keywords: Highly pathogenic avian influenza, H5N1, environmental contamination, water sample, nucleic acid detection.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Furness, Professor Robert
• Authors: Furness, R. W., Gear, S. C., Camphuysen, K. C. J., Tyler, G., de Silva, D., Warren, C. J., James, J., Reid, S. M., and Banyard, A. C.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Pathogens
• Publisher: MDPI
• ISSN: 2076-0817
• ISSN (Online): 2076-0817
• Published Online: 12 April 2023
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Pathogens 12(4): 584
• Publisher Policy: Reproduced under a Creative Commons License