To the Editor:—
Attention was recently directed to the communication on the prediction of poliomyelitis incidence in epidemic years (The Journal, September 4, p. 53). An effort was made to determine whether or not the experience in San Francisco coincided with that presented for Chicago.As a result of a review of our recent epidemic years, apparently the observation can be made that the epidemiologic statistical pattern of infantile paralysis is still obscure, and the following conclusions may be reached:
The 1943 accelerated incidence in San Francisco should not be considered epidemic.
No standard for predicting the peak of an epidemic can be determined at least in San Francisco, as the interval from initial increase to peak varies between the years 1930 and 1934 from four to seven weeks.
Again, for San Francisco, it is not possible to assert with assurance that seasonal prevalence is fixed or