As more information emerges about the mass shooting at a Catholic school in Minneapolis, parents are faced with the difficult task of discussing the tragedy with their children.

The shooting at Annunciation Catholic School in Minneapolis on Wednesday killed two children, and injured 15 other kids and three adults. Here's what we know about the victims.

Early immune pressure and co-occurring mutations drive changes in hepatitis C virus fitness and evolution, revealing key dynamics in the establishment of chronic infection.