Objective To investigate the biting rate dynamics of mosquitoes in Beijing Olympic Forest Park (BOFP), and to analyze the correlation between biting rate and the population density measured by the lamp trapping method. Methods A dynamic monitoring of the biting rate and population density of mosquitoes was conducted by human landing catch and CO ₂ trapping lamp from July to September, 2013. Pearson correlation analysis was performed to analyze the relationship between the mosquito density measured by the lamp trapping method and biting rate, and a linear regression analysis was used to build a linear model for prediction of the biting rate based on the mosquito density measured using the CO ₂ trapping lamp. Results Culex pipiens pallens was the dominant species of mosquito community in Beijing, followed by Cx. tritaeniorhynchus. The biting rate of mosquitoes continuously increased from July to September, and a trough of lamp trapping mosquito density was detected in August. There was a linear correlation between lamp trapping mosquito density and biting rate in July and September, while there was no correlation between them in August. Conclusion The mosquito density measured by the lamp trapping method is closely correlated with the biting rate of mosquitoes. Cx. pipiens pallens is the dominant species of mosquito community in Beijing, and the probability of people being bitten by mosquitoes is significantly correlated with the population density of Cx. pipiens pallens.

Objective To investigate the barrier effect of rivers on the spread of rodent plague. Methods The data of the rodent plague foci in Dehong autonomous prefecture of Yunnan province, China, from January 1982 to December 2007 were collected. The numbers of townships and plague foci with rodent plague were recorded in each county (city) and in each of the three regions divided by the Daying River and Longchuan River (national borders-Daying River, Daying River- Longchuan River, and Longchuan River-prefecture borders) in each year. The epidemic intensity values of five counties (cities) and three regions were calculated according to the entropy index and adjusted for area size. The difference in adjusted epidemic intensity between the five counties (cities) or the three regions were analyzed using the Kruskal-Wallis H test. Results During 1982-2007, in Yingjiang, Lianghe, Longchuan, Ruili, and Mangshi, rodent plague was epidemic for 16, 11, 19, 11, and 10 years, respectively, and the numbers of plague foci were 159, 96, 93, 76, and 35, respectively. There was no significant difference in the overall distribution of adjusted epidemic intensity between the five counties ( H=8.277, P=0.082). In the three regions (national borders-Daying River, Daying River-Longchuan River, and Longchuan River-prefecture borders), plague was epidemic for 16, 25, and 10 years, respectively, and the numbers of plague foci were 103, 321, and 35, respectively. There was a significant difference in the overall distribution of adjusted epidemic intensity between the three regions ( H=19.738, P=0.000), and significant differences were also observed between the region from Longchuan River to Daying River and the region from national borders to Daying River or the region from Longchuan River to prefecture borders ( χ ²=18.423, P=0.003; χ ²=26.692, P=0.000). Conclusion Rivers may have a barrier effect on the spread of rodent plague in Dehong prefecture, which may be related to the effects of rivers on the geographical distribution of Yersinia pestis and the community, population and distribution of the host and vector fleas of Y. pestis.

Objective To investigate the prevalence of 6 rodent-borne pathogens, in some suburban areas of Beijing, China. Methods TaqMan fluorescent probe-based quantitative real-time PCR (qPCR) was used for laboratory evaluation. Plasmid standards were prepared and standard curves were plotted. Detection thresholds were determined according to the reevaluated data. From January to June, 2017, the trap-at-night method was used to capture rodents in Chaoyang, Huairou, Mentougou, and Pinggu districts of Beijing, tissue samples were collected to extract nucleic acids, and qPCR was used to detect pathogens. Results A total of 160 rodents were captured, among which there were 59 Rattus norvegicus rodents, 69 Mus musculus rodents, 4 Apodemus peninsulae rodents, 25 Niviventer confucianus, and 3 Sorex spp.. The examination of spleen tissues showed that all rodents except Sorex were infected with Rickettsia typhi (8.1%), Orientia tsutsugamushi (1.3%), Anaplasma phagocytophilum (5.6%), Leptospira interrogans (18.7%), or Bartonella spp. (5.0%). No Francisella tularensis was detected in all rodents. There were co-infections with various pathogens including Leptospira interrogans and A. phagocytophilum in R. norvegicus and M. musculus. Conclusion Rodents in Beijing carry the pathogens of common, emerging and reemerging infectious diseases. The distribution investigation of animal hosts and vectors of these pathogens in these areas and prevention and treatment of related infectious diseases should be strengthened.

Objective To investigate Liaoning virus(LNV) in mosquitoes in Chaoyang district, Beijing. Methods According to the Surveillance for Vector Density-Mosquito (GB/T 23797-2009), mosquitoes were collected by CO₂ traps in 2014 and 2015. Reverse transcription-polymerase chain reaction was used to detect LNV. Molecular characteristics were carried out by Mega 6.0. Results A total of 9 811 mosquitoes were collected and Culex pipiens pallens (8 968/9 811, 91.41%) was the main species. The sample BJCY14007 was positive for LNV. LNV has two branches (serotypeⅠand serotypeⅡ) based on the molecular characteristics of the segment 10. BJCY14007 was more related to NE97-12 (representative strain, serotypeⅠ). Conclusion The LNV was firstly detected in Beijing. It deserves further investigation LNV prevalence in mosquito, human population and other hosts for risk assessment.

Objective To understand distribution and seasonality of Culex tritaeniorhynchus in Chaoyang district, Beijing. Methods According to the Surveillance Methods for Vector Density-Mosquito (GB/T 23797-2009), mosquitoes were collected by the CO₂ traps. To determine the spatial distribution, the two types of sampling sites including park (or green spaces) with waters and human populated area were chosen in different geographical locations, and mosquitoes were trapped from August to September. To find out the seasonality, the mosquitoes were trapped per ten days from May to October in the same place. Results The proportions of sampling sites with Cx. tritaeniorhynchus between 2^nd Ring Road and 3^rd Ring Road, 3^rd Ring Road and 4^th Ring Road, 4^th Ring Road and 5^th Ring Road, outside 5^th Ring Road were 1/2, 3/3, 4/8 and 3/6 respectively, and there were no statistically different in different area subdivided by ring road (P=0.570); the proportions of sampling sites with Cx. tritaeniorhynchus of parks (or green spaces) with waters and human populated areas were 76.92% (10/13) and 16.67% (1/6) respectively, and were statistically different (P=0.020); the Cx. tritaeniorhynchus densities between 2^nd Ring Road and 3^rd Ring Road, 3^rd Ring Road and 4^th Ring Road, 4^th Ring Road and 5^th Ring Road, outside 5^th Ring Road were 0.09, 0.16, 0.31 and 4.97 mosquitoes per trap-hour respectively; the mean (m) and variance (S²) of densities of Cx. tritaeniorhynchus were 1.56 and 24.03, S²/m=15.42>1, which suggested that Cx. tritaeniorhynchus clumped distributed; the first appearance of Cx. tritaeniorhynchus was in the last twenty days of July, then its constituent ratio showed a trend from rise to decline and the peak period of its density was in September. Conclusion Culex tritaeniorhynchus tends to spread from suburb to city with the improvement of water conversation, and clumped distributed in urban area of Chaoyang district. Vigilance is needed to the epidemic risk of Japanese encephalitis, and public health department should strengthen the prevention and control measures.

Objective To establish a comprehensive assessment model for plague surveillance for Qinghai province, China, and to evaluate the national-level surveillance stations in the natural focus of Himalayan marmot plague for improvement of performance and quality of plague surveillance. Methods A total of 25 comprehensive assessment indicators reflecting the surveillance quality were selected, which included the population survey of marmots and other small rodents, the flea index and burrow track fleas from the primary host of plague, marmots, and the plague bacteriological and serological measurements. The analytic hierarchy process (AHP) was used to establish a comprehensive assessment model for plague surveillance and to evaluate the plague surveillance in 4 national-level surveillance stations in the natural focus of Himalayan marmot plague in Qinghai. Results According to the scores obtained from the AHP model, the 4 national-level surveillance stations were in the order of Ulam county (1.9286), Gonghe county (1.3174), Golmud city (1.0692), and Yushu Tibetan Autonomous Prefecture (0.9477). Conclusion The results of plague surveillance evaluation based on AHP are reasonable and reliable. It provides strong evidence for the management and improvement of plague surveillance.

Objective To establish a comprehensive assessment model for plague surveillance for Qinghai province, China, and to evaluate the national-level surveillance stations in the natural focus of Himalayan marmot plague for improvement of performance and quality of plague surveillance. Methods A total of 25 comprehensive assessment indicators reflecting the surveillance quality were selected, which included the population survey of marmots and other small rodents, the flea index and burrow track fleas from the primary host of plague, marmots, and the plague bacteriological and serological measurements. The analytic hierarchy process (AHP) was used to establish a comprehensive assessment model for plague surveillance and to evaluate the plague surveillance in 4 national-level surveillance stations in the natural focus of Himalayan marmot plague in Qinghai. Results According to the scores obtained from the AHP model, the 4 national?level surveillance stations were in the order of Ulam county (1.9286), Gonghe county (1.3174), Golmud city (1.0692), and Yushu Tibetan Autonomous Prefecture (0.9477). Conclusion The results of plague surveillance evaluation based on AHP are reasonable and reliable. It provides strong evidence for the management and improvement of plague surveillance.

Objective To investigate the species composition and population density of mosquitoes and the prevalence of Japanese encephalitis virus (JEV) infection in Linyi county of Shanxi province, China. Methods Mosquitoes were collected by light traps and used for identification of JEV. NS1 sequences of JEV were amplified using RT-PCR from mosquito nucleic acid. Samples with positive amplification of NS1 were further sequenced. Results A total of 4424 mosquitoes (6 species, 4 genera) were collected, of which 52.0% were Culex tritaeniorhynchus, 41.2% were Cx. pipiens pallens, and few were Anopheles sinensis and other species. Mosquito density gradually increased from June to August. The constituent ratio of Cx. tritaeniorhynchus among all mosquitoes increased month by month. A total of 2109 individuals of Cx. tritaeniorhynchus were pooled into 77 batches before nucleic acid detection of JEV, of which 10 batches were positive. Five of the positive samples were sequenced, and alignment with GenBank sequences indicated the presence of genotypeⅠ JEV. Conclusion The mosquito density is high in July and August in Linyi county, and the constituent ratio of Cx. tritaeniorhynchus and JEV positive rate are relatively high. The two indices could be used as important early warning indicators for prevention of Japanese encephalitis.

Objective To investigate the activity of metabolic enzymes in Anopheles sinensis from some regions in Henan province, China and the mechanism of metabolic resistance to deltamethrin in An. sinensis. Methods An. sinensis samples were collected from Tongbai county, Huaibin county, and Yongcheng city (county-level) in Henan province in August 2010. The adult mosquitoes of the next generation were divided into deltamethrin-resistant group and deltamethrin-sensitive group by filter contact method according to WHO standard. The activity of metabolic enzymes in deltamethrin-resistant mosquitoes, including nonspecific esterase, glutathione S-transferase (GST), and P450 monooxygenase, was measured by microtiter plate method. The laboratory sensitive strain of An. sinensis was used as the control. Results The activity of types A and B nonspecific esterases was significantly higher in the deltamethrin- resistant samples from Tongbai, Huaibin, and Yongcheng than in the control group ( t=2.41, t=3.30, t=10.31, t=7.67, t=7.90, t=11.17, P<0.05 for all comparisons). The activity of GST in the deltamethrin-resistant samples from Yongcheng and Huaibin was higher than that in the control group ( t=3.687, t=2.484, P<0.05 for both comparisons). There were no significant differences in the P450 monooxygenase activity between the deltamethrin-resistant samples from Huaibin, Yongcheng, and Tongbai and the control group ( t=-1.489, t=0.397, t=-0.413, P>0.05 for all comparisons). Conclusion The deltamethrin resistance in An. sinensis from Yongcheng and Huaibin are related to the increased activity of esterase and GST, but the deltamethrin resistance in An. sinensis from Tongbai is only related to the increased activity of esterase.

Objective To evaluate the trapping effect of MT-1 carbon dioxide light - traps on adult Aedes albopictus. Methods A factorial design was conducted to compare six CO₂ flow groups and one blank control at 7 sampled sites during 10 surveillance periods. The traps were placed at each sample site to collect mosquitoes, and were replaced with new devices with the flow rate adjusted every two hours between 02:00-22:00. Results (1)A total of 1122 adult mosquitoes were collected and identified as two species, including 939 Ae. albopictus;(2)Mosquitoes were collected more efficiently in the CO₂ flow groups (F＝3.05, P＝0.01), and the highest number of collected mosquitoes was observed at a flow rate of 6 L/min;(3)The numbers of captured Ae. albopictus were statistically different in distinct surveillance periods(F＝2.98, P＝0.03), and most of them were captured during 18:00-20:00 and 04:00-06:00;(4)No difference was found in the captured Ae. albopictus at the sample sites (F＝0.47, P＝0.80). Conclusion The MT-1 carbon dioxide light-traps could be used to collect adult Ae. albopictus at a recommended CO₂ flow rate of 6 L/min at dusk.

Objective To determine the efficacy and feasibility of synthetic amorphous silica against Dermanyssus gallinae. Methods Forced contact tests were used in accordance with GB/T 13917.1-2009. Results The 3% synthetic amorphous silica was painted on three types of board at 6 g a.i/m². For cement boards, the 24 h mortality was 100% and the residual efficacy lasted about 45 days; for silicate glass cotton board, the 24 h mortality was 100% and the residual efficacy lasted about 90 days; and for alkyd resin varnish boards, the 48 h mortality was 100% and the residual efficacy lasted about 60 days. Conclusion Synthetic amorphous silica was effective in the control of D. gallinae.

Objective To develop standard laboratory rearing techniques for Aedes albopictus in order to provide consistent, quality, standardized testing insects for use in pesticide experiments. Methods Using standard rearing techniques, the mosquitoes were bred under controlled rearing conditions. The reliability of multiregional rearing was examined based on the weight of female adults 3 days after eclosion from three batches of mosquitoes. Results All three batches resulting from standard rearing techniques yielded qualified Ae. albopictus based on the average weight, with high repeatability and low relative deviation (8.28%) of weights. As shown from the average weights of mosquitoes bred using different dietary formulas, all three approaches were applicable to different regions and the relative deviation was low (7.69%). Conclusion The rearing technique was repeatable and effective in developing weight-uniform Ae. albopictus for pesticide experiments.

【Abstract】 Objective To know the resistance situation and its geographic distribution of German cockroaches (Blattella germanica) in Chaoyang district. Methods German cockroaches were trapped from eight sites belonging to different geographic zone. The insecticides film contact method was used to the detection of resistance. The resistance level of German cockroach from different sites was analyzed by average linkage method. Results There was significant difference among the resistance level  of cockroach to seven insecticides (χ2＝26.880, P＝0.000). It had the highest resistance to organophosphorus insecticides (χ2＝20.494，P＝0.000). The resistance levels of cockroach from 8 sites were also significantly different (χ2＝29.143，P＝0.000), which could be classified into four groups by cluster analysis. Conclusion The resistance of cockroach to insecticides was different in different areas in Chaoyang district, so the same control method.

【Abstract】 Objective To analyse effect factors of trap method and bait method, and to discuss how to improve the accuracy of surveillance methods. Methods Two methods combined with powder trace method were used in this study and its effect factors were analyzed. Results The invalid areas surveyed by bait method accounted for 53%, suggesting that the inducement of sweet potato was very weak. Successful surveillance area accounted for 8% and 67% by trap method and powder?trace method, respectively, showing that the reason leading to the insensitivity of rodent to trap method was its strong repellence to new substance. Conclusion There are many factors to affect the surveillance of rodent such as the repellence of rodent to new substance, the lure of baits, the abundance of food, the sensitivity of surveillance facility and the layout of surveillance sites. It is good to improve the accuracy of surveillance by single factor analysis.

【Abstract】 Objective To study the evaluation methods of larvicides registration and field test. Methods Larvae were collected from breeding sites in the external environment or adult mosquitoes were trapped to oviposit in man-made areas. Results  The relative population index (RPI) of larvae from breeding sites was under 5 after treatment by 1% temephos granules for 4 weeks, which had a good control effect. RPI of larvae from wasted tyres was also less than 5 after treatment for 4 weeks, while it was under 10 after treatment for 3 weeks in cement pool. Conclusion The field control effect and registration of quick-acting insecticides could be evaluated by the above mentioned two methods.

Objective To understand and analyze malaria situation in Yongcheng city of Henan province during 2003-2005 and provide evidence for malaria control and prevention. Methods Data on malaria epidemic situation,vector surveillance,blood examination of fever cases and serological surveillance on students were collected and analyzed. Results 890 malaria cases were reported and average incidence of malaria was 2.17 per ten thousand in Yongcheng city during 2003-2005. The number of reported malaria cases in 2004 and 2005 were 13.00 and 3.23 times of that of the previous year,respectively. The number of malaria cases reported from 10 townships in eastern part of the city accounted for 80.22% of the total cases. Most of malaria cases were students and farmers. Positive rate was 5.82% in blood examination of fever patients and 15.31% in IFA of students,respectively. 154 Anopheles sinensis were captured and no An.anthropophagus was found in vector surveillance in 2005. Conclusion Dramatic re-emergence of malaria was observed in Yongcheng city. Various control measures of malaria should be strengthen and rising trend of malaria epidemic situation should be timely suppressed.

Objective To understand the effects of urbanization on the communities' structure of the cockroaches in Suzhou.Methods Sticky traps nightly method.Results The average density of the indoor cockroaches was 0.53 pest/trap from 2004 to 2005,and it was 0.05(pest/trap) from 1997 to 2001.The proportion of Blattella germanica,Periplaneta americana andP.fuliginosa were 80.30%,17.04% and 2.66% respectively in 2004-2005,and in 1997-2001 they were 86.69%,7.37% and 5.95% respectively.The average density of the cockroaches was 0.49(pest/trap) in the old districts from 2004 to 2005,and in the new districts it was 0.58 pest/trap.In old districts,the proportion of the three species of cockroaches were 75.71%,22.31% and 1.98% respectively,but in new districts they were 84.52%,12.19% and 3.28% respectively.The density and communities structures of the cockroaches were significant different in 2004-2005 from those in 1997-2001(P<0.01).Conclusion It indicated that urbanization affected the structure and quantity of the cockroaches in Suzhou.

Objective To find out the effects of the lime piece positions on piece positive rate in rat trace survey in the train compartments. Methods Use the lime method to obtain the rat density at the four corners and beside doors of the train compartment,respectively record the number of positive lime pieces and negative ones,then grade the positive rates of lime pieces. Results The positive lime pieces beside doors of the train compartment is obviously more,compared with those at four corners ( P<0.01),the proportion of strong positive lime pieces in the positive lime pieces between the two positions is very high and the difference is very obvious ( P<0.01). Conclusion Compared with the lime placement at the four angles of a passenger train compartment,the placement of lime beside doors is convenient,practical,and has higher positive rate,thus deserving popularizing.

Objective To improve original bait method,establish new bait-box method for monitoring rodent density,and primarily discuss the feasibility of the methods. Methods The quantity of bait eaten by rodents was observed. The masculine rate of bait-box and the bait's daily-losing-weight were tested in the area where the rodent density being in a high level. Results The masculine rate of bait-box and the bait's daily-losing-weight were linear interrelated. Two curves were fit logistic curve in density of rodent while the real density of rodent was relatively stable. They reach maximum and tend to be stable in 60th day. Conclusion This method is tend to monitor the density of rodent long at the same places.

Objective To investigate the natural infection rate of Angiostrongylus cantonensis, Strobilocercus fasciolaris, Capillaria hepatica and Trichinella spiralis in rats from countryside of Lianjiang district of Guangdong province. Methods The parasites above were examined in lungs,livers and diaphragms of rats captured from both indoors and outdoors. Results 236 rats belong to six species were obtained in total. Rattus flavipectus is the most ( 58.5%) dominant species in number. R.norvegicus is the second ( 22.5%). Mus musculus, Suncus murinus, Rattus sladeni and Rattus confucianus are totally 19%. Total infection rate of the parasites in these rats is about 35.59%. The natural infection rates of A.cantonensis,Strobilocercus fasciolaris,C.hepatica and T.spiralis are 17.37%,16.95%,1.27% and 0 respectively. Among different rat species,parasite infection rate of R.norvegicus is the highest ( 66.00%) and R.flavipectus is the second ( 35.50%). Furthermore the natural infection rates of A.cantonensis in rats captured from the wild is significantly higher than that from the domicile. S.fasciolaris is easier to be found in rats captured from the wild too. However, C.hepatica is only discovered in R.norvegicus captured from the domicile. Conclusion The infection of A.cantonensis and S.fasciolar is prevalent and serious in rats from countryside of Lianjiang district of Guangdong province,the infection of C.hepatica also exists in the rats.

Objective To evaluate the effects of a paste bait "BAIMIESHI"against roach,by laboratory test and in the field application.Methods To test it according to the GB/T 17322.8-1998 and the GB/T 17322.11-1998.Results The results of laboratorial test showed that a 100% mortality was achieved during 72 h by both forced and unforced feeding tests.The values of LT ₅₀ were 11.7 h and 13.7 h,respectively.A 100% mortality was also achieved during 102 h by the analogous field test,and the value of LT ₅₀ was 20.4 h.In the field application,with a dosage of 0.4 g/m ²,the density reduction rate(DRR) came to 63.6% and 89.0% at the 3 ^rd and 30 ^thday,respectively,while with a dosage of 0.8 g/m ²,the DRR came to 82.3%,99.2% and 98.3% at the 3 ^rd,30 ^th and 60 ^th day,respectively.Conclusion The roach bait "BAIMIESHI" has been proved to be very effective on roach control with some of features:less amount used,long term residual effect and high safety,it can be used in the plases that children playing,top grade hotels and electrical equipment.

Objective:To design a new mosquito trap.Methods:To design the light source,the setting of the vanes and the speed depending on the trapping efficacy.Results:Changing the setting of the vanes to avoid the mosquito crashing against them for the integrality of the samples remodeled the reported mosquito trap by ultraviolet radiation.Firstly,the daylight lamp,mosquito-luring lamp and ultraviolet radiation were tested on the mosquito-luring efficacy.Then,the two 10 W lamps were used as light source.The relationship between the wind speed and the injuries of samples were studied and the wind speed of the trap mouse center was confirmed as 1.7 m/s.Conclusion:The new designed DW-1 Mosquito Trap has not only better mosquito trapping efficacy,but also better integrality of the samples.

The toxicity of some bacillus larvicidal proteins depends on their binding affinity with larval gut cell membrane. Preparation of membrane vesicle of mosquito larvae gut was essential to research on the larvicidal mechanism and to improvement of the larvicidal proteins by protein engineering methods. In this study, we prepared and analysed larval mosquito gut cell membrane fraction. While, we prepared its mouse antisera and observed the biological effect of the antisera on mosquito larvae. The results showed that the main protein band of the membrane vesicle was that of 51kDa and the larval mortality caused by the antisera was obviously higher than that by the control sera. This suggested that the antibody components indeed have binding activity in the midgut.

The toxicity of trebon, a new type pesticide lowtoxic to man and animals, has been studied on the rat flea Xenopsylla cheopis.It was revealed that ① the efficacy of trebon with following different treatment i.e.impropation > spreading> residual smearing, LD ₁₀₀ being 5ppm, 0.3mg/m ² and 5.0mg/m ², respectively;② although the 100% mortality (24 hour) can be expected with either trebon.or fendona or deltamethrin with the dose of 5mg/m ² and above, trebon showed a better knock-down effect than that of fendona or deltamethrin, the KT _{50 of trebon was 2.5 times that of fendona (spreading method), and 8.2 times that of deltamethrin (residual smearing); ③ when used as residual smearing, trebon can keep its efficacy more than 365 days under room temperature, and about 35 days at 50℃.}

The orthogonal design and relevant statistical analyses were employed to evaluate the effects of various factors including temperature, humidity and density on egg hatching, immatural development and cultivation qualities. involving the weights of both adult and larvae, adult longevity and fecundity, of Xenopsylla cheopis in laboratory. The results showed that the temperatrure acted as amajor factor conditioning the immatural development and adult weight, the humidity was responsible mainly for egg hatching, immatural survivorship and adult longevity, and the density threw an effect principally on larval weight and adult fecundity. The theoretical optima obtained were: for egg hatching, 28℃, 95% RH; for immature development, 28℃, 75%RH and 20 larvae/ml medium; for weights, 22℃, 85%RH and 20 larvae/ml medum; and for longevity, 22℃, 85% RH and 60 larvae/ml medium; and for fecundity, 28℃, 85% RH and 20 larvae/ml medium. Based on the optima mentioned above, a comprehensive condition, i.e. 25℃, 75%, 85% or 90%RH (for larvae, adults and eggs, respectively) and a density of 20 larvae/ml medium, should be recommended for the cultivation of X. cheopis in laboratory.

This paper reports some results of the influences of larva density and fodder thickness on the larva growth and the adult quality of Oriental rat flea, reared by artificial method in vitro.The results show that suitable density of larva are 20-40 larvae in 1 ml fodder and suitable thickness of fodder is about 1cm, for X. cheopis respectively.