Previous accounts of the 1916 devastating epidemic have been faulty. The unique features of the epidemic and
its sudden appearance have never been explained. A New York laboratory was passaging poliovirus in primate brains, a
technique which increased pathogenicity. I propose that highly virulent virus escaped and caused the epidemic. Scientists,
technical and animal house staff were unaware that they could be infected by poliovirus which could then infect others.
All laboratory workers must be constantly reminded of the dangers which can arise from the escape of pathogens from