The Chicken or the Egg? Possibly the next most important
development in virology was the proof that embryonated or
fertilized hen’s eggs could be used to culture a variety of
important animal and human viruses. Ernest Goodpasture, working
at Vanderbilt University in the USA, showed in 1931 that it was
possible to grow fowlpox virus – a relative of smallpox – by
inoculating the chorioallantoic membrane of eggs, and incubating
them further. While tissue culture had in fact been practiced
for some time – for example, as early as the 1900s,
investigators had grown “vaccine virus” or the smallpox vaccine
now called vaccinia virus in minced up chicken embryos suspended
in chicken serum – this technique represented a far cheaper and
much more “scalable” technique for growing pox- and other
suitable viruses. The Official Discovery of Influenza Virus
Influenza viruses in pigs Also in 1931, Robert Shope in the USA
managed to recreate swine influenza by intranasal administration
of filtered secretions from infected pigs