Canary pox vaccination with live embryo-attenuated virus.

A live-virus embryo-propagated canary pox vaccine was developed that can be safely and effectively applied by a single needle wing-web stab. Reactions to vaccination with passages lower than the 72nd passage were sometimes excessive in proliferative response. The 72nd and 100th embryo passages produced a more restricted lesion at the site of inoculation. The vaccine does not cause a systemic reaction or metastasis from the inoculation site.