Since 2020, the emergence and global dissemination of high pathogenicity avian influenza (HPAI) H5Nx clade 2.3.4.4b infection has had devastating effects in wild and domestic bird populations, and resulted in spillover events in many terrestrial and marine mammalian species, including susceptible captive big cat collections, and feral and domestic feline species. The recent outbreaks in dairy herds in the USA following proposed exposure to infection from wild birds, with subsequent spread to in-contact mammals, demonstrates successful interspecies transmission of this virus and warrants close monitoring. In this literature review, we provide an overview of HPAI H5N1 infection in feline species to date, focusing on domestic but also captive wild cats, looking at the epidemiology, clinical and pathological presentations and management, and a current perspective on risk, testing and strategies to prevent infection.
Keywords: H5N1; avian influenza; pathology; presentation; prevention; review; risk.
Understanding H5N1 bird flu in cats: what we know now and what we have learned from the pastSince 2020, H5N1 bird flu has spread widely around the world, severely affecting both wild and domestic birds. This virus has also been found in mammals, particularly marine mammals, captive wild cats, and pet and stray cats. Recently, the virus was detected in dairy cows in the USA, most likely after contact with wild birds carrying the virus. The fact that it can spread between different kinds of animals shows how adaptable this virus is and why it is necessary to monitor it. In this article, we review what is currently known about H5N1 infections in cats. We look at how cats are infected, the signs they show and what happens internally. We also discuss how the illness is diagnosed and managed, and what can be done to reduce the risk of infection. Our aim is to give a clearer picture of the threat this virus poses to both domestic and wild cats, and what steps can be taken to protect public health.