INFLUENZA: Rainbow Virus Showing Structure
An influenza virus particle rendered in translucent rainbow colours showing internal structures. Flu viruses are covered by spikes of Haemagglutinin (slender knob-like projections) and Neuraminidase (the squarish-looking projections), hence the H and N names, such as H5N1. Flu viruses have a segmented genome that can get jumbled up during replication (gene mixing) when a cell is infected with more than one strain of the virus. This allows different strains to easily form from existing types. Flu occurs in seasonal epidemics and periodically as major pandemics. Buy the animation and other flu graphics here.