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Vaccinia Reporter Viruses for Quantifying Viral Function at All Stages of Gene Expression
Published on: May 15, 2014
Smallpox virus plaque phenotypes: genetic, geographical and case fatality relationships
Victoria A Olson1, Kevin L Karem1, Scott K Smith1
1Poxvirus Team, Poxvirus and Rabies Branch, Division of Viral and Rickettsial Diseases, National Center for Zoonotic, Vector-Borne and Enteric Diseases, Coordinating Center for Infectious Diseases, Centers for Disease Control and Prevention, Mail Stop G-06, 1600 Clifton Road NE, Atlanta, GA 30333, USA.
The Journal of General Virology
|March 7, 2009
Summary
Smallpox (Orthopoxvirus variola) virus comet formation, linked to extracellular enveloped virus (EEV) production, correlates with variola virus phylogeny and origin, not directly with case-fatality rates. Pathogenicity likely involves complex host and pathogen interactions.
Area of Science:
- Virology
- Infectious Diseases
- Epidemiology
Background:
- Smallpox, caused by Orthopoxvirus variola, is eradicated but remains a historical concern.
- Variability in smallpox case-fatality rates (CFRs) is not fully understood.
- The extracellular enveloped virus (EEV) form is hypothesized to spread orthopoxvirus infections.
Purpose of the Study:
- To investigate the association between comet formation (EEV production) in variola virus strains and their pathogenicity.
- To determine if EEV production correlates with historical smallpox outbreak case-fatality rates (CFRs).
Main Methods:
- Analysis of comet formation phenotypes in a diverse collection of variola virus strains.
- Correlation of comet formation with variola virus strain phylogeny and geographical origin.
- Comparison of comet formation and plaque size with outbreak-related CFRs.
Main Results:
- Increased comet formation in variola virus strains associated with strain phylogeny and geographical origin.
- No direct correlation found between increased comet formation and higher outbreak-related CFRs.
- A potential association between plaque size and CFR within specific variola virus clades was observed.
Conclusions:
- EEV production, indicated by comet formation, is linked to variola virus strain characteristics but not directly to overall pathogenicity or CFR.
- Variola virus pathogenicity is likely multifactorial, involving interactions between host and pathogen elements.
- Further research is needed to elucidate the precise mechanisms driving variola virus virulence.
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