Analysis on the Seasonal Distribution of Infectious Diseases by using Centralization and Circular Distribution

The Seasonal distribution of 10 notifiable communicable diseases during the past 38 years in Dongcheng district Beijing was analysised by using vector compound mode_centraligation and circular distribution. The Centraligation Value M and Circular Distribution value R were calculated respectively accounding to the following different stages:before implementation of Expanded Program on Immunization (EPI)(1958～1978) and after implementation of EPI(1979～1996).The resvlt showed that there was almost no change in the seasonal distribution of all the communicable cable diseases except the peak of measles was one month delayed after implementation of EPI.