The family of Paramyxoviridae contains viruses that induce a wide range of distinct clinical illnesses in humans.


These include measles virus, which in rare instances is followed by subacute sclerosing panencephalitis (SSPE); mumps virus, which has symptoms of parotitis, orchitis and encephalitis, and the parainfluenza viruses which are respiratory pathogens.


Virions are enveloped and enclose a helical nucleocapsid containing single-stranded RNA.

Most virions are roughly spherical (about 200nm in diameter) but they can be much larger and more pleomorphic.

The virus envelope is a lipid bilayer, studded with virus encoded glycoproteins which have properties of haemagglutination and fusion (the F protein).


By transmission electron microscopy, and negative staining, the helical ribonucleo-protein capsid has a "herring-bone" appearance.



© 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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