The current epidemic of avian influenza has killed over 58 million birds in the U.S. as of February 2023. Following on the heels of the COVID-19 pandemic, large outbreaks of viruses like bird flu raise the specter of another disease jumping from animals into humans. This process is called spillover.
I’m a veterinarian and a researcher who studies how diseases spread between animals and people. I was on the Colorado State University veterinary diagnostic team that helped detect some of the earliest cases of H5N1 avian influenza in U.S. birds in 2022. As this year’s outbreak of bird flu grows, people are understandably worried about spillover.
