The human immunodeficiency virus (HIV) is discovered “hiding” between the cells of the gut.
A 3D model of the dengue virus reveals a shape like a soccer ball with an outer coating of glycoproteins.
Killer T-cells captured in the act of destroying HIV-infected cells.
A germ-spreading sneeze unleashes a shower of large liquid droplets and a moist gas cloud of smaller ones.
The measles virus can spread easily among people who have no immunity against it, as the current outbreak shows.