Objective To investigate the dynamic structure and distribution of plague hosts and vector communities in various regions of Zhejiang province to understand the epidemiological characteristics of plague. Methods The gray mathematical theory was adopted to measure the maximum effect indices based on relevant data of different regions, hosts, and flea populations. Results Fifteen types of animal host (25 588) as well as eight types of body flea (1944) were subject to quality measurement, resulting in differences between each pair of groups, indicating a dominant species among host animals of each region and a vector population in each dominant community. Given adequate privilege of each dominant group, early warning, prevention and investigation shall be implemented. Conclusion A typical mathematical matrix can be formed based on the number of rodents and species of fleas. The quality measurement indicated that the larger vector and flea numbers resulted in high measurement Results, suggestive of high risk of plague in the region.

【Abstract】 Objective To understand the population structure and distribution of host animals and fleas in historical flavipectus plague focus in ZheJiang, and to analyze the phenomenon of mixed and cross?channeling between house and wild mouse, so as to provide basic data for plague monitoring. Methods The species diversity of plague hosts and fleas were analyzed based on the monitoring data in 2007-2008. Results There were 3 orders, 4 families, 9 genus and 15 species animals found in historical flavipectus plague epidemic area, and about 4 families, 7genus, 7 species fleas were collected in this areas. Among the host animals, Rattus flavipectus accounted for 13.11%, 36.30% for R.norvegicus, 16.49% for Apodemus agrarius and 17.39% for Suncus  murinus. The fleas in those host were 32.91%, 42.20%, 14.56% and 0.74%, respectively. Leptopsylla segnis was the dominant species with the proportion of 64.34%. Monopsyllus anisus was 19.87% and Xenopsylla cheopis was 9.64%. The species diversity between host animals and fleas was significant difference. The index of species diversity was higher(H＞1), the population quantity of host animals was more stable. Conclusion The quantity and species of host animals were very rich. The cross?channeling phenomenon between house and wild mouse was obvious. Some fleas can parasitize many species of rodents, which will cause a serious threaten to human once the plague prevailed among rodents occurs. Presently, the reliability of surveillance data in some surveillance sites can not be ensured, and the species of animal was also singular.

Objective This experiment was carried out to investigate the resistance of Culex pipiens quinquefasciatus Say to eight pestsides and make the corresponding control statics.It was very important to control and prevent Cx.pipiens quinquefasciatus Say.Methods LC ₅₀ of eight commercial pesticids were measured on the fourth instar larvae by larva soaked method(recommended by WHO).Results The resistance ratios of Cx.pipiens quinquefasciatus to DDV,Bassa,Acetofenate,Permethrin and Deltamethrin were 3.53,1.58,2.91,8.66,4.67 for Wenzhou;3.50,1.67,1.61,6.69,5.33 for Shaoxing;5.35,3.23,2.59,6.72,2.53 for Quzhou;3.53,3.02,2.75,12.10,4.00 for Jinhua;The resistance ratios of Cx.pipiens quinquefasciatus from different cities to DDV,Bassa,Acetofenate,Permethrin,Deltamethrin,DDT,D-allethrim and beta-cypermethrin were 3.78,3.06,1.54,5.15,9.00,1.25,3.27,2.62 for Huzhou;4.24,3.43,1.27,5.32,11.08,1.27,3.20,2.75 for Jiaxing.Conclusion The results showed that Cx.pipiens quinquefasciatus has developed resistance to the eight tested pestsides,especially to Permethrin and Deltamethrin.