ABSTRACT
<p><b>OBJECTIVE</b>To find out the vector ability and function of Nosopsyllus wualis leizhouensis in the transmitting plague.</p><p><b>METHODS</b>In T: 19 degrees C +/- 1 degrees C, RH: 85% +/- 5%, data regarding the vector ability as cluster spreading, single flea spreading, single flea transmitting plague to single animal, formative bacterial embolus and infection fleas life-span through experiments was gathered.</p><p><b>RESULTS</b>The rate of infection on fleas was 94.64%, with 100% transmission rate of colony to spread, and 30% from single flea spreading to single animal. In the experiment of single flea transmission, all of the 388 rattus loseas were bitten by the fleas with bacterial, but only 9 animals were characteristically infected with the transmission potential, vector efficiency, survival potential of embolus, vector index as 0.360, 0.257, 0.868 and 0.223 respectively. The mean survive days of infected flea feed with blood were 17.58 (1 - 58), and the mean survive days of hunger infected flea were 7.25 (1 - 16). Formative bacterial embolus days were 8.80 (2 - 16) and the rate of embolus flea was 78.12%.</p><p><b>CONCLUSION</b>Nosopsyllus wualis leizhouensis could serve as vector and important in the mode of plague transmittion.</p>