Division Laboratory criteria

• Laboratory criteria for case confirmation

  At least one of the following two laboratory tests:

  • Isolation of smallpox (variola virus) from a clinical specimen followed by sequencing (designated P4 laboratories only)

  • Detection of Variola virus nucleic acid in a clinical specimen followed by sequencing

Laboratory results need to be interpreted according to the vaccination status

• Laboratory criteria for a probable case

• Identification of orthopox virus particles by EM