The phrase ‘spread like a virus’ could soon carry quite a bit more weight, according to new research. While viruses have long been thought to spread by infecting a cell, replicating, and then moving on to the next, researchers found through live video microscopy that the poxvirus vaccinia spreads four times faster than replication would allow. The virus revealed a mechanism in which infected cells are tagged by two surface proteins; these markers repel the virus on toward uninfected cells, making the process of infection much faster. (Check out a video of vaccinia’s spread below the fold…)

Video courtesy Laura Gallagher, Imperial College of London