False-colour transmission electron micrograph (TEM) of a vaccinia virus particle, a member of the orthopoxvirus group. Virus particles (virions) of th

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False-colour transmission electron micrograph (TEM) of a vaccinia virus particle, a member of the orthopoxvirus group. Virus particles (virions) of this group appear brick-shaped; complex membrane structures surround the nucleoid, a genetic core of DNA. Replication of the DNA & formation of viral progeny occurs in the host cell's cytoplasm; most other viruses replicate in the cell nucleus. The vaccinia virus causes cowpox, a disease of cattle. It was first used by Jenner in 1796 to protect against smallpox, a related human disease, in the process of vaccination. Magnification: x16,000 at 6x7cm size.

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Size: 2765px × 3543px
Photo credit: © CNRI/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: cowpox, false-coloured, orthopoxvirus, poxvirus, smallpox, vaccination, vaccinia, virus