"In early September, scientists at the University of Florida confirmed that a bottlenose dolphin, found dead in a canal on the Gulf Coast in March, carried a highly pathogenic kind of avian influenza. Its brain was inflamed.

True to its label, this virus is skilled at infecting birds, but it sometimes goes farther afield. A few months after the dolphin’s death, another mammal, a porpoise, was found stranded and weak on the west coast of Sweden. It subsequently died, bearing the same virus. Between these events there was another concerning case in Colorado, when a man tested positive for bird flu. He was a state prison inmate, at work in a prerelease job that involved culling birds on a poultry farm where the infection had struck.

Later analysis questioned whether the Colorado man was truly infected or whether a testing swab had merely picked up a big load of virus in his nose. But he was not the sole human in the past year to test positive for bird flu, specifically H5N1. A 79-year-old man in Britain, who lived closely with about 20 pet ducks, also tested positive for the bird virus around Christmas of 2021.

If these four events — one dead dolphin, one dead porpoise and two men testing positive for a dangerous bird virus — seem disconnected and insignificant, perhaps it’s because you haven’t heard of “viral chatter.” The phrase was coined decades ago by Dr. Donald Burke, a veteran infectious disease researcher and former dean of the University of Pittsburgh Graduate School of Public Health, and refers to when a virus episodically spreads from wild animals into humans, occasionally causing small chains of transmission. It’s a warning signal that’s often recognized too late."

David Quammen reports in an opinion piece for the New York Times October 31, 2022. [2]