ON NUKADA'S LAW CONCERNING THE INCIDENCE OF WHOOPING COUGH.

Abstract

Recently Nukada comfirmed a very interesting fact, that the rate of incidence of whooping cough was the lower, the smaller the number of brothers.
The present author studied 2 1, 0 43 children in Yokosuka City and well acertained the law found by Nukada. He also found this fact was more marked in younger children.
Nukada explained his law by a hypothesis of latent infection. The author assumed, however, that the mother contracted the desease from her childrenand transmitted the immunity to her following children.