World Library  
Flag as Inappropriate
Email this Article

Mumps virus

Article Id: WHEBN0000606671
Reproduction Date:

Title: Mumps virus  
Author: World Heritage Encyclopedia
Language: English
Subject: Mumps, Viral disease, List of infectious diseases, Cytomegalovirus esophagitis, Simian-T-lymphotropic virus
Collection: Mumps, Rubulaviruses
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Mumps virus

Mumps virus
TEM micrograph of the mumps virus.
Virus classification
Group: Group V ((-)ssRNA)
Order: Mononegavirales
Family: Paramyxoviridae
Genus: Rubulavirus
Type species
Mumps virus

Mumps virus is the causative agent of mumps, a well-known common childhood disease characterised by swelling of the parotid glands, salivary glands and other epithelial tissues, causing high morbidity and in some cases more serious complications such as deafness. Natural infection is currently restricted to humans and the virus is transmitted by direct contact, droplet spread, or contaminated objects.

It is considered a vaccine-preventable disease, although significant outbreaks have occurred in recent years in developed countries such as America, in areas of poor vaccine uptake. These have allowed the further evaluation and ennumeration of its efficacy (~75–85% after two doses of MMR).[1]

The mumps virus belongs to the genus Rubulavirus in the family Paramyxovirus and is seen to have a roughly spherical, enveloped morphology of about 200 nm in diameter.[2] It contains a linear, single-stranded molecule of negative-sense RNA 15,384 nucleotides long.[2]

Contents

  • Structure 1
  • Basic morphology 2
  • Genotypes 3
  • Pathogenesis 4
  • Vaccination 5
  • References 6

Structure

The mumps virus is a roughly spherical particle made up of concentric layers of fatty lipids, large protein molecules, and nucleic acid. It is dotted with large 'spikes' made up of protein that enable it to gain entry to host cells. Inside lies a core of a single, long molecule of RNA wrapped up in protein that is released into the cell.

Basic morphology

Electron micrograph of the ribonucleoprotein of mumps virus

Electron microscopy (EM) revealed that the mumps virus (MuV), like other members of the Paramyxoviridae, has an enveloped virion of roughly spherical or pleiomorphic (variable) shape.[2] Paramyxovirus particles can have sizes ranging from 120–450 nm in diameter.

These particles consist of what is known as a ribonucleoprotein (RNP) complex: a single-stranded, linear RNA genome coated by nucleocapsid proteins (NP) in association with an RNA polymerase complex of both large (L) and phosphoprotein (P) subunits. It has been estimated that over 2,000 such NP molecules coat the genome along with about 250 P and 25 L molecules.

This RNP structure interacts with the viral envelope via matrix (M) proteins that are evenly distributed around the virion. The envelope, a lipid bilayer derived from the host-cell plasma membrane, harbours multiple copies of a number of glycoproteins required for virus entry and exit: hemagglutinin-neuraminidase (HN), fusion (F), and the small hydrophobic (SH) protein.

This molecular assembly of protein, RNA, and lipids allows a single virus to bind to and infect specific cells and replicate itself and finally exit the cell to be transmitted to the next susceptible host.

Genotypes

Although there is only one serotype of the mumps virus, according to recent update by WHO (June 2012), there are currently 12 genotypes A-N, (namely A, B, C, D, F, G, H, I, J, K, L, N) excluding (E and M). L-Zagreb vaccine strain comes under genotype N. The typing scheme is based on the sequence of the small hydrophobic (SH) gene.

There are several subgenotypes (D1, D2 G1, G2, H1, H2) which are designated by numerals after the letter. G2 is the current subgenotype circulating in the Indian subcontinent.[3]

Among vaccine strains, Jerryl Lynn and Rubini belong to genotype A, Urabe is genotype B. It is not clear yet if there is any clinical significance to the genotypes.

Pathogenesis

The mumps virus can infect ependymal cells in the central nervous system.[4]

Vaccination

Several strains are used to vaccinate against mumps. These include the strains Jerryl Lynn, L-Zagreb, Leningrad-3 and Rubini and Urabe.

Universal mumps vaccination was introduced in the United Kingdom in 1988.

References

  1. ^ CDC list of articles pertaining to the contemporary American mumps outbreaks
  2. ^ a b c Hviid A, Rubin S, Mühlemann K (March 2008). "Mumps".  
  3. ^ Mishra, B.; Pujhari, S. K.; Dhiman, V.; Mahalakshmi, P.; Bharadwaj, A.; Pokhrel, S.; Sharma, D.; Sharma, M.; Bhatia, D.; Ratho, R. K. (2013). "Genotyping and subtyping of mumps virus isolates from the Indian subcontinent". Archives of Virology 158 (11): 2359–2363.  
  4. ^ Tardieu M, Weiner HL (January 1982). "Viral receptors on isolated murine and human ependymal cells". Science 215 (4531): 419–21.  
  • "Mumps virus". NCBI Taxonomy Browser. 11161. 
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.