Rapid communication Open Access
Like 0


In June 2023, a fatal disease outbreak in cats occurred in Poland. Most cases tested in Poland (29 of 47) were positive for highly pathogenic avian influenza (HPAI) A (H5N1) virus. Genetic analyses revealed clade with point mutations indicative of initial mammalian hosts adaptations. Cat viral sequences were highly similar (n = 21), suggesting a potential common infection source. To investigate possible infection routes, our group tested food samples from affected households. HPAI H5N1 virus was detected in one poultry meat sample.


Article metrics loading...

Loading full text...

Full text loading...



  1. Centers for Disease Control and Prevention (CDC). Technical Report: Highly Pathogenic Avian Influenza A(H5N1) Viruses. Atlanta: CDC; Updated 7 Jul 2023. [Accessed 2 Aug 2023]. Available from: https://www.cdc.gov/flu/avianflu/spotlights/2022-2023/h5n1-technical-report_june.htm#human-cases
  2. World Health Organization (WHO). Influenza A(H5N1) in cats – Poland. Geneva: WHO. 16 July 2023. Available from: https://www.who.int/emergencies/disease-outbreak-news/item/2023-DON476
  3. Alkie TN, Cox S, Embury-Hyatt C, Stevens B, Pople N, Pybus MJ, et al. Characterization of neurotropic HPAI H5N1 viruses with novel genome constellations and mammalian adaptive mutations in free-living mesocarnivores in Canada. Emerg Microbes Infect. 2023;12(1):2186608.  https://doi.org/10.1080/22221751.2023.2186608 
  4. Bordes L, Vreman S, Heutink R, Roose M, Venema S, Pritz-Verschuren SBE, et al. Highly Pathogenic Avian Influenza H5N1 Virus Infections in Wild Red Foxes (Vulpes vulpes) Show Neurotropism and Adaptive Virus Mutations. Microbiol Spectr. 2023;11(1):11.  https://doi.org/10.1128/spectrum.02867-22 
  5. Vreman S, Kik M, Germeraad E, Heutink R, Harders F, Spierenburg M, et al. Zoonotic Mutation of Highly Pathogenic Avian Influenza H5N1 Virus Identified in the Brain of Multiple Wild Carnivore Species. Pathogens. 2023;12(2):168.  https://doi.org/10.3390/pathogens12020168 
  6. Siegers JY, Ferreri L, Eggink D, Kroeze EJBV, te Velthuis AJW, van de Bildt M, et al. Evolution of highly pathogenic H5N1 influenza A virus in the central nervous system of ferrets. PLoS Pathog. 2023;19(3):e1011214.  https://doi.org/10.1371/journal.ppat.1011214 
  7. Kuiken T, Rimmelzwaan G, Van Riel D, Van Amerongen G, Baars M, Fouchier R, et al. Avian H5N1 influenza in cats. Science. 2004;306(5694):241.  https://doi.org/10.1126/science.1102287 
  8. Frymus T, Belák S, Egberink H, Hofmann-Lehmann R, Marsilio F, Addie DD, et al. Influenza Virus Infections in Cats. Viruses. 2021;13(8):1435.  https://doi.org/10.3390/v13081435 
  9. Choroba kotów (Odpowiedzi) - Arkusze Google. [Feline disease (answers) - Google Sheets]. Polish. [Accessed 12 Jul 2023]. Available from: https://docs.google.com/spreadsheets/d/1mxrfKbes4JoEDyxSisYFPindgd_N7Mer9e7KM7biIxo/edit?fbclid=IwAR1k30LBVVN3s-5LOwI5dOWKUNaNwcZsaR0DUVgO5DZRJaMwFBGXuyo_nvQ#gid=1893899732
  10. Miau.PL • Zobacz wątek - Tajemnicza śmiertelna choroba kotów. [See the topic - Mysterious deadly feline disease]. Polish. [Accessed 12 Jul 2023]. Available from: https://forum.miau.pl/viewtopic.php?p=12742263
  11. Oxford Nanopore Technologies (ONT). ONT Ligation sequencing influenza whole genome protocol. Oxford: ONT. [Accessed 13 Jul 2023]. Available from: https://community.nanoporetech.com/docs/prepare/library_prep_protocols/ligation-sequencing-influenza-whole-genome/v/inf_9166_v109_revb_24aug2022
  12. Song W, Wang P, Mok BWY, Lau SY, Huang X, Wu WL, et al. The K526R substitution in viral protein PB2 enhances the effects of E627K on influenza virus replication. Nat Commun. 2014;5(1):5509.  https://doi.org/10.1038/ncomms6509 
  13. Bogs J, Kalthoff D, Veits J, Pavlova S, Schwemmle M, Mänz B, et al. Reversion of PB2-627E to -627K during replication of an H5N1 Clade 2.2 virus in mammalian hosts depends on the origin of the nucleoprotein. J Virol. 2011;85(20):10691-8.  https://doi.org/10.1128/JVI.00786-11 
  14. Harder TC, Teuffert J, Starick E, Gethmann J, Grund C, Fereidouni S, et al. Highly pathogenic avian influenza virus (H5N1) in frozen duck carcasses, Germany, 2007. Emerg Infect Dis. 2009;15(2):272-9.  https://doi.org/10.3201/eid1502.080949 
  15. Kandeil A, Patton C, Jones JC, Jeevan T, Harrington WN, Trifkovic S, et al. Rapid evolution of A(H5N1) influenza viruses after intercontinental spread to North America. Nat Commun. 2023;14(1):3082.  https://doi.org/10.1038/s41467-023-38415-7 
  16. World Health Organization (WHO). WHO information for the molecular detection of influenza viruses. Geneva: WHO; 2021. [Accessed 12 Jul 2023]. Available from: http://www.who.int/influenza/gisrs_laboratory/collaborating_centres/list/en/index.html

Data & Media loading...

Supplementary data

Submit comment
Comment moderation successfully completed
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error