The viruses of variola, vaccina, cowpox and ectromelia. Neutralization tests on the chorio-allantois with unabsorbed and absorbed immune sera.
D000482:Allantois; D000818:Animals; D015605:Cowpox; D004480:Ectromelia; D004482:Ectromelia, Infectious; D006801:Humans; D007106:Immune Sera; D009500:Neutralization Tests; D012899:Smallpox; D014615:Vaccinia; D014616:Vaccinia virus; D012901:Variola virus; D014780:Viruses
D007106:Immune Sera
ECTROMELIA, INFECTIOUS; SMALLPOX; VACCINIA; VIRUSES