Studies on Free Fleas at Rooms in the Plague Natural Foci of Hebei Province

To understand the species,yearly changes and seasonal fluctuation of the indices at rooms in the plague natural foci of Hebei Province, and to study their epidemiological significance in transporting plague for conducting the works of plague prevention and control, we statisticed and studied the relative materials from 1988～2002. As a result, 5 species of fleas were found. Pulex irritans acconunted for 99%. The free fleas at rooms could be captured from 5～8 months. The fluctuation of the indices closely related to the temperature. The highest indices was in July,average 0.104.