Interference between inactivated and active influenza viruses in the chick embryo

摘要: Abstract Interference by ultraviolet-inactivated influenza virus with propagation of the active homo- or heterotypic agents in endoderm chick embryo allantois has been re-evaluated respect to dosage and timing two injections, using infectivity titrations for assay. By varying (a) interfering dose terms hemagglutinin units; (b) intervals between its injection challenge serial decimal dilutions virus; (c) period incubation after challenge, following results were obtained. The time required establish solid interference decreases size dose; i.e., when increasingly more inactivated particles are provided per cell. With 850 HA units no evidence viral multiplication was obtained upon at 9 hours, whereas 20–100 extensive, yet not complete 24 hours. If inocula given simultaneously a 2-hour interval first part second infectious cycles found proceed before further spread process arrested, unless inactive large. In that case homotypic preparations affected yields initial significant extents. all instances, where as fully established, 20 agent, directly proportional dose. smaller (