Discussion on Time Distribution of Epidemic Hemorrhagic Fever in SonghuaJiang Prefecture 1989—1995

The Time distribution of epidemic hemorrhagic fever in Songhuajiang Prefecture during 1989 to 1995 was investigated by using a round distributive method.It was confirmed that there was an epidemic season during August 25 to Feburary 22 next year.Its peak was between Oct 10 to Jan 8 next year.Its epidemic phase was in Jan 9 to Feb 22 next year.The other time was interval phase. 89.58% of the total cases were concentrated in the period of epidemic season.79.84% of the total cases were concentrated in the peak time. The resultsprovided a scientific base for infectious disease prevention and control.