Cultivation of the Virus of the Common Cold in the Chlorio-Allantoic Membrane of the Chick Embryo

We have reported the successful cultivation of the virus of the common cold in an anaerobic medium containing chick-embryo tissue., Our purpose in the present communication is to describe the cultivation of this virus in the chorio-allantoic membrane of the developing chick-embryo. This technic for the cultivation of the viruses of infectious diseases was developed by Woodruff and Goodpasture for the propagation of fowl pox virus, and later successfully applied by them and others to a number of different viruses. Wilson Smith reported the cultivation of a mouse-passage strain of human influenza virus by this means. A more elaborate series of similar experiments has already been recorded by Burnet. Our own experiment was as follows: In September, 1936, a nasal washing was obtained from an individual with a typical acute head cold of less than 24 hours' duration. The washing was passed rapidly through a Seitz filter, and concentrated to one-fourth its original volume by vacuum distillation. Two-tenths cc. of this bacteria-free filtrate, almost immediately after its isolation from the human source, were inoculated into the chorio-allantoic membranes of 12-day chick-embryos according to the technic described by previous authors. At the end of 2 or 3 days the membranes were removed and ground up with non-toxic broth so as to make a suspension of approximately 20%; 0.2 cc. of this were inoculated into each of a second series of eggs. Similarly these membranes were ground up and inoculated into a third. It is noteworthy that the small opaque foci visible on the membranes and which Burnet described as resulting from the cultivation of influenza virus were also observed by us.