Dr  Sampurna Roy  MD

Paramyxoviruses are spherical enveloped particles with a diameter ranging from 100 to 800 nm containing a nucleocapsid with a RNA genome.

In common with the Influenza viruses (Orthomyxoviruses)  they have spikes in the envelope with hemagglutinin activity and in some cases also with  neuraminidase activity.

In contrast, however, to influenza viruses they are antigenically stable and genetic recombination does not occur.

The paramyxoviruses that infect humans include:

Parainfluenza Virus 1,2,3,4A, & 4B

Mumps virus

Measles virus

Respiratory syncytial virus