In recent years, there has been an increase in the detection of A(H5N1) viruses in non-avian species worldwide, including terrestrial and marine mammals, both wild and domestic (companion and production). Since 2022, twenty-two countries on three continents, including the Americas, have reported outbreaks in mammals to the World Organization for Animal Health (OIE). Historically, from early 2003 to August 25, 2025, 990 human cases of avian influenza A(H5N1) were reported to the World Health Organization (WHO), including 475 deaths (48% fatality rate), in 25 countries worldwide.
