Influenza virus (an Orthomyxovirus) is responsible for acute upper respiratory disease, usually accompanied by fever and myalgia.





Virions are usually roughly spherical and about 200nm in diameter.
The envelope contains rigid "spikes" of haemagglutinin and neuraminidase which form a characteristic halo of projections around negatively stained virus particles.


The viral genome is composed of eight segments of ssRNA.
The helical ribonucleo-protein is not often seen,
but occasional particles show evidence of internal helical components.

© Copyright Dr Linda M Stannard, 1995

This page was written by Dr Linda Stannard, on behalf of the Division of Medical Virology, UCT.

In Memory of Dr Linda Stannard, 10 May 1942 - 17 October 2016

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Recipient of Key Resource Award

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