Gonorrhea, Infertility, and Population Decline in Yap during the Japanese Occupation

Susan L. Cassels, Princeton University

An understudied component of Japan's colonial empire is their occupation of Micronesia from 1919 to 1945. This paper focuses on the small island of Yap where the Japanese impact on the native population and environment was devastating; the population diminished by more than 25% during the occupation, the crude birth rate was very low, and gonorrhea was rampant. The main objective of this paper is to determine how much gonorrhea affected population growth. Our microsimulation model, based on the prevalence of gonorrhea on Yap in 1930, estimates that gonorrhea reduced population growth by 20%, which potentially was enough to reverse the sign of population growth. Secondly, this paper explores the underlying causes and modes of transmission of the gonorrhea epidemic in Micronesia during the Japanese occupation. Historical evidence points toward colonial labor exploitation, environmental change and disruption of familiar societal institutions as the proximate causes.