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Vaccinia Virus Infection & Temporal Analysis of Virus Gene Expression: Part 1
Published on: April 8, 2009
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The origin of the variola virus
Igor V Babkin1, Irina N Babkina2,3
1Laboratory of Molecular Microbiology, Institute of Chemical Biology and Fundamental Medicine, Novosibirsk 630090, Russia. i_babkin@mail.ru.
Viruses
|March 13, 2015
Summary
The variola virus (VARV), causing smallpox, likely emerged 3000-4000 years ago in East Africa. Environmental changes and camel introduction may have triggered its evolution from a cowpox-like ancestor.
Area of Science:
- Virology
- Evolutionary Biology
- Epidemiology
Background:
- Smallpox, caused by the variola virus (VARV) within the Orthopoxvirus genus, has been a significant human pathogen.
- Despite eradication, understanding the emergence of novel pathogens like VARV remains crucial.
- The evolutionary origins of VARV have been a subject of scientific inquiry.
Purpose of the Study:
- To determine the emergence timeline and geographic origin of the variola virus (VARV).
- To investigate potential environmental and host-related factors contributing to VARV's evolution.
- To estimate the evolutionary rate of VARV.
Main Methods:
- Comparative genomic analysis of VARV and related orthopoxviruses.
- Integration of epidemiological and historical data on smallpox.
- Phylogenetic analysis to date viral emergence and estimate evolutionary rates.
Main Results:
- VARV likely emerged 3000 to 4000 years ago in East Africa.
- Estimated evolutionary rates for VARV are approximately 2 × 10-6 to 4 × 10-6 substitutions/site/year.
- The introduction of camels and climate shifts in Africa are hypothesized triggers for VARV divergence.
Conclusions:
- The study provides a temporal and geographic framework for VARV emergence.
- Environmental and ecological factors played a role in the evolution of VARV.
- Understanding past viral emergence events can inform future pathogen risk assessment.
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