[Studies on the danger of contamination of small-pox vaccine by ECBO viruses].
D004340:Drug Contamination; D006801:Humans; D012899:Smallpox / Q000276:immunology*; D012900:Smallpox Vaccine; D014612:Vaccines; D012901:Variola virus; D014780:Viruses
D012900:Smallpox Vaccine; D014612:Vaccines
SMALLPOX/immunology; VACCINES