Genetic analysis has revealed the H7N9 virus is made up of four different bird flu strains, one from ducks, two from chickens and one from migratory birds. Zoonoses are becoming more common due to agricultural intensification, involving not only the disruption of wildlife habitat, but also the placement of densely packed livestock animals at the cleared site. As livestock comes into contact with wildlife, and humans come in contact with livestock, it becomes more and more likely that a pathogen will “spillover” from animals to humans. Studying the effects of H7N9 in all of its animal hosts can shed light on how it might affect humans, and may help us find effective treatments and vaccines. Read more here.