> Until 2020, when the new H5N1 strain began to spread extensively among wild birds, most big outbreaks occurred among poultry. But now, with wild birds acting

> Until 2020, when the new H5N1 strain began to spread extensively among wild birds, most big outbreaks occurred among poultry. But now, with wild birds acting as conduits, it’s not just the biggest outbreak ever among poultry, causing the death of at least 150 million animals so far, but it is also steadily expanding its reach, including to mammal species like dolphins and bears. H5N1 is buying up lots of lottery tickets.