Asymptomatic infection with clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) in carnivore pets, Italy, April 2023.
Ana Moreno1
Francesco Bonfante2
Alessio Bortolami2
Irene Cassaniti3,4
Anna Caruana5
Vincenzo Cottini6
Danilo Cereda7
Marco Farioli7
Alice Fusaro2
Antonio Lavazza1
Pierdavide Lecchini8
Davide Lelli1
Andrea Maroni Ponti8
Claudia Nassuato6
Ambra Pastori2
Francesca Rovida3,4
Luigi Ruocco8
Marco Sordilli8
Fausto Baldanti3,4,9
Calogero Terregino2,9
Affiliations9 institutions
Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna (IZSLER), Brescia, Italy.
Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe), Legnaro (Padua), Italy.
Department of Clinical, Surgical, Diagnostic and Paediatric Sciences, University of Pavia, Pavia, Italy.
SC Microbiology and Virology, IRCCS Policlinico San Matteo, Pavia, Italy.
Dipartimento di Igiene e Prevenzione Sanitaria-ATS Brescia, Brescia, Italy.
Dipartimento Veterinario e Sicurezza degli Alimenti di origine animale-ATS Brescia Direzione Generale, Brescia, Italy.
General Directorate of Welfare, Regione Lombardia, Milan, Italy.
Sanità Animale e Farmaci Veterinari, Ministero della Salute, Rome, Italy.
These authors contributed equally to this work and share last authorship.
In April 2023, an outbreak of clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) viruses carrying the T271A mammalian adaptive mutation in the PB2 protein was detected in a backyard poultry farm in Italy. Five domestic dogs and one cat living on the premises had seroconverted in the absence of clinical signs. Virological and serological monitoring of individuals exposed to the virus proved the absence of human transmission, however, asymptomatic influenza A(H5N1) infections in mammalian pets may have important public health implications.
highly pathogenic avian influenza H5N1 virusPB2 mutationpet carnivoresphylogenetic analysisserologysilent infectionInfluenza A virusInfluenza A Virus, H5N1 SubtypeInfluenza in BirdsAnimalsAsymptomatic InfectionsBirdsDogsHumansItalyMammals
Structured evidence records
Evidence records
4 total
Molecular Adaptation1 records
Molecular AdaptationExtraction confidence 0.90
Key finding
The H5N1 virus detected in Italy contained the PB2 T271A mutation known to promote mammalian adaptation.
An outbreak of clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) viruses carrying the T271A mammalian adaptive mutation in the PB2 protein was detected in a backyard poultry farm in Italy.
Genes or proteins
PB2
Mutations
T271A
Mechanism types
polymerase_activity; mammalian_adaptation
Outbreak Investigation1 records
Outbreak InvestigationExtraction confidence 0.85
Key finding
An outbreak of H5N1 occurred in a backyard poultry farm in Italy in April 2023, with asymptomatic infections detected in dogs and a cat residing there.
In April 2023, an outbreak of clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) viruses carrying the T271A mammalian adaptive mutation in the PB2 protein was detected in a backyard poultry farm in Italy. Five domestic dogs and one cat living on the premises had seroconverted in the absence of clinical signs.
Method
serology; virological monitoring
Transmission direction
animal-to-animal
Geographic raw
Italy
Country inferred
Italy
Outbreak setting
backyard poultry farm
Outbreak time
April 2023
Outbreak scale
five domestic dogs and one cat
Serological Evidence1 records
Serological EvidenceExtraction confidence 0.95
Key finding
Serological testing showed that five domestic dogs and one cat in Italy had seroconverted to clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) without showing symptoms.
Five domestic dogs and one cat living on the premises had seroconverted in the absence of clinical signs.
Method
serology
Sample type
serum
Spillover Event1 records
Spillover EventExtraction confidence 0.95
Key finding
Serological evidence indicated that domestic dogs and a cat were asymptomatically infected with avian influenza A(H5N1), consistent with bird-to-mammal spillover in Italy.
In April 2023, an outbreak of clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) viruses ... was detected in a backyard poultry farm in Italy. Five domestic dogs and one cat living on the premises had seroconverted in the absence of clinical signs.
Method
serology
Study design
field surveillance
Transmission direction
animal-to-human
Geographic raw
Italy
Country inferred
Italy
Citation context
References
23 references
Reference network
Force-directed citation graph. OmniVira-indexed references are prioritized and recursively expanded up to three steps.
Authors’ response: Highly pathogenic influenza A(H5N1) viruses in farmed mink outbreak contain a disrupted second sialic acid binding site in neuraminidase, similar to human influenza A viruses
Experimental infection of dogs with highly pathogenic avian influenza virus (H5N8)
Yuk
2017
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Focolai di Influenza Aviaria da sottotipo H5N1: informazione e indicazioni
Italian Ministry of Health - General Dir
2021
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Influenza aviaria ad alta patogenicità H5N1 –Dispositivo recante misure di controllo esorveglianza per prevenire l’introduzione e la diffusione dell’influenza aviaria
