Abstract
106 EID50 of the standard passage virus of influenza, PR 8, were inoculated into 11-days developing eggs. The production of the incomplete virus was observed from 8 to 48 hours after inoculation with respect to the EID50/HA ratio as the indicator of the presence of incomplete particles.
1. In chorioallantoic fluid, the EID50/HA ratio increases rapidly in the beginnings of the viral growth and then slowly. Its maximum value is around 106.6 (48 hours after inoculation).
2. In chorioallantoic membranes, EID50/HA ratio increases slowly to 14 hours after inoculation. Then it takes constant value, 103-4. Always its value is lower than the value in the case of the chorioallantoic fluid from the same egg.
3. When the inoculum size of 106 EID50, mid poind of the von Magnus's standard passage and undiluted passage, the incomplete form of the virus is found mainly in infected chorioallantoic membranes and there is no incomplete particle in chroioallantoic fluid later than 14 hours after inoculation.
4. These results were confirmed by three different extraction methods but the findings was the same.
