As an avian influenza virus panzootic is underway, the threat of a human pandemic is emerging. Infections among mammalian species in frequent contact with humans should be closely monitored. One mammalian family, the Felidae, is of particular concern. Felids, known as felines or cats, are susceptible to avian influenza virus infection. Felines prey on wild birds and may serve as a host for avian influenza virus adaptation to mammals. Feline-to-feline transmission has been demonstrated experimentally [1], and real-world outbreaks have been reported [2,3]. Domestic cats are a popular human companion animal and thus provide a potential pathway for zoonotic spillover of avian influenza viruses to humans. Here, we provide a systematic review of the scientific literature to describe the epidemiology and global distribution of avian influenza virus infections in felines reported over time. We aim to provide a comprehensive background for the assessment of the current risk, as well as bring awareness to the phenomenon of AIV infection in felines.

The authors have declared no competing interest.

We acknowledge the support of the University of Maryland Baltimore, Institute for Clinical & Translational Research (ICTR) and the University of Maryland Strategic Partnership: MPowering the State (MPower).

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

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Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

All data produced in the present study are available upon reasonable request to the authors.