THE RELATION OF SEX, PREGNANCY AND MENSTRUATION TO SUSCEPTIBILITY IN POLIOMYELITIS

MANY of the general features of the distribution of poliomyelitis are reflections of the widespread dissemination of the virus as it is affected by immunity in the population resulting from previous exposure. Within this broader pattern of distribution there are further restrictions and selectivities in the occurrence of the frank disease that are indicative of the operation of other factors of susceptibility or resistance. Among the many who are exposed to the virus, the preponderant result of which is subclinical immunization, the more frequent occurrence of frank poliomyelitis under particular circumstances and in particular categories of individuals affords some indication . . .