False-colour transmission electron micrograph of vaccinia virus. A member of the poxvirus family, it is the largest & most complex of the vertebr- ate

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False-colour transmission electron micrograph of vaccinia virus. A member of the poxvirus family, it is the largest & most complex of the vertebr- ate viruses (230x300 nanometres in size). The virus particles appear brick-shaped & consist of a complex structure of membranes surrounding the genetic core of DNA - the nucleoid. Replication of the DNA & formation of the 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 & humans that causes skin lesions resembling those of smallpox, but without the associated systemic disturbances. Magnification: x58,800 at size.

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Size: 2673px × 3543px
Photo credit: © DR HEATHER DAVIES/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: cowpox, orthopoxvirus, poxvirus, smallpox, vaccination, vaccinia, virus