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. 2023 Aug;28(31):2300366.
doi: 10.2807/1560-7917.ES.2023.28.31.2300366.

Outbreak of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus in cats, Poland, June to July 2023

Katarzyna Domańska-Blicharz  1 , Edyta Świętoń  2 , Agnieszka Świątalska  3 , Isabella Monne  4 , Alice Fusaro  4 , Karolina Tarasiuk  1 , Krzysztof Wyrostek  1 , Natalia Styś-Fijoł  1 , Aleksandra Giza  2 , Marta Pietruk  2 , Bianca Zecchin  4 , Ambra Pastori  4 , Łukasz Adaszek  5 , Małgorzata Pomorska-Mól  6 , Grzegorz Tomczyk  1 , Calogero Terregino  4 , Stanisław Winiarczyk  5   7
Affiliations

Outbreak of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus in cats, Poland, June to July 2023

Katarzyna Domańska-Blicharz et al. Euro Surveill. 2023 Aug.

Erratum in

  • Authors' correction for Euro Surveill. 2023;28(31).
    Eurosurveillance editorial team. Eurosurveillance editorial team. Euro Surveill. 2024 Mar;29(10):240307c. doi: 10.2807/1560-7917.ES.2024.29.10.240307c. Euro Surveill. 2024. PMID: 38456213 Free PMC article. No abstract available.

Abstract

BackgroundOver a 3-week period in late June/early July 2023, Poland experienced an outbreak caused by highly pathogenic avian influenza (HPAI) A(H5N1) virus in cats.AimThis study aimed to characterise the identified virus and investigate possible sources of infection.MethodsWe performed next generation sequencing and phylogenetic analysis of detected viruses in cats.ResultsWe sampled 46 cats, and 25 tested positive for avian influenza virus. The identified viruses belong to clade 2.3.4.4b, genotype CH (H5N1 A/Eurasian wigeon/Netherlands/3/2022-like). In Poland, this genotype was responsible for several poultry outbreaks between December 2022 and January 2023 and has been identified only sporadically since February 2023. Viruses from cats were very similar to each other, indicating one common source of infection. In addition, the most closely related virus was detected in a dead white stork in early June. Influenza A(H5N1) viruses from cats possessed two amino acid substitutions in the PB2 protein (526R and 627K) which are two molecular markers of virus adaptation in mammals. The virus detected in the white stork presented one of those mutations (627K), which suggests that the virus that had spilled over to cats was already partially adapted to mammalian species.ConclusionThe scale of HPAI H5N1 virus infection in cats in Poland is worrying. One of the possible sources seems to be poultry meat, but to date no such meat has been identified with certainty. Surveillance should be stepped up on poultry, but also on certain species of farmed mammals kept close to infected poultry farms.

Keywords: H5N1; HPAI; Poland; avian influenza; cats; veterinary.

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Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure 1
Figure 1
Locations of cats infected with highly pathogenic avian influenza A(H5N1) virus, Poland, June–July 2023 (n = 25)
Figure 2
Figure 2
Epidemic curve of cats infected with highly pathogenic avian influenza A(H5N1) virus, Poland, June 2023 (n = 25)
Figure 3
Figure 3
Location of outbreaks of highly pathogenic avian influenza A(H5N1) virus in poultry and wild birds, Poland, during the 2022/23 season
Figure 4
Figure 4
Genetic network of complete genome sequences of highly pathogenic avian influenza A(H5N1) virusesa of the CH genotype collected from birds in Europe and from cats (n = 19) in Poland, June–July 2023
See this image and copyright information in PMC

References

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