How humans can and can’t catch bird flu

Scientists are on alert for changes in the H5N1 or bird flu virus that could signal it is adapting to spread among humans. The virus has caused serious, sometimes fatal, infections among people and has long been on the list of viruses with pandemic potential. Any expansion to a new mammal species is concerning. An outbreak of bird flu among cattle herds in the United States led to the first known case of transmission between a cow and a human, after a Texas farm worker caught the virus. Previously, the virus had mostly been passed to humans through close contact with wild birds or infected poultry. The spread of bird flu to an increasing number of species and its widening geographic reach have raised the risks of humans being infected by the virus, according to the World Organisation for Animal Health (WOAH). The infections in cattle are from the same subtype of bird flu that has been infecting wild birds and poultry flocks globally, also killing several mammal species that likely contracted the virus from consuming sick or dead birds. In February, a deadly type of bird flu was confirmed on the mainland of Antarctica for the first time. Scientists