Published online by Cambridge University Press: 15 May 2009
Vaccinia virus inoculated on the chorio-allantois and causing infection spread to the uninoculated part of the membrane, the embryo, the allantoic and amniotic fluids and the yolk within 1 day.
The virus grew in the embryo and possibly in the uninoculated part of the chorio-allantois, but in the latter no macroscopic lesions were detected.
Virus increased in amount in the allantoic fluid and may have grown in the lining of the allantoic sac; it did not increase in the amniotic fluid; it was present in yolk and increased slightly but its local growth was doubtful.
The presence of haemagglutinin and complement-fixing antigen was related to the amount of virus.
Allantoic fluid from infected eggs could be a ready source of antigen for complement-fixation.