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 This study was intended to elucidate the spatial distribution characteristics of fly density, find correlated environmental factors, and respond to the need of fly control in disaster fields. Methods Respectively, in the study, the spatial statistical analysis was used to detect the spatial aggregation of fly population on the scales of village and town. Furthermore, spatial error regression was performed to uncover the correlated environmental factors with fly density on the same two geographic scales. Results The spatial aggregation of fly population displayed statistical significance in flooding sites on the level of village(Moran's I=0.387, P=0.016)and town(Moran's I=0.381, P=0.039), which means that such spatial pattern was not original from random process. Accordingly, as the spatial regression shown, the fly density correlated with different environmental factor on the scales of village and town; The lighting index values was related to village(Correlation Coefficient=0.514)and town(Correlation Coefficient=1.472)scales, while the slop values related only to the village scales(Correlation Coefficient=-2.398). Conclusion Present paper not only shed light on the fly spatial distribution pattern in flooding area in Fangshan, but also could provide direction for the fly control for any disaster sites being similar to flooding region in Fangshan.

Objective The Centers for Disease Control(CDC), at all levels, are the major institutions undertaking the vector surveillance; the application situation of the four vectors surveillance standards(FVSS)in the Chinese CDC system was analyzed here, and the promotion of FVSS on the business of CDC institutions was investigated at the same time. Methods In the study, questionnaire was used to investigate the awareness and application of FVSS by the CDC institutions, the promotion function of FVSS on the business of CDC institution, and the problem of execution of FVSS by the CDC institutions. Results As the results shown, almost 80 percent of among the CDC institutions, were aware of the FVSS's promulgating and had used the FVSS, and 79.14 percent of them believed that the application of FVSS could standardize their surveillance on vectors. In addition, the FVSS were useful in national hygienic city inspection, hygienic assurance for large-scale events, and emergency response to public health events. However, some problems were also found from the survey:first, 37.41 percent institutions didn't receive any FVSS training courses, the FVSS training should been expanded to cover more institutions; second, many methods in FVSS induced disagreement in vector surveillance and should be modified in the future; third, the FVSS should be consistent with the assessment standard system on the vector control. Conclusion The application situation of FVSS and promotion of FVSS in vector control program by CDC institutions was elucidated, which provided the guideline not only for the using of the FVSS by the CDC institution but also the modification of FVSS in the future.

German cockroach (Blattella germanica), the dominant species of cockroaches in China, has an important role in research due to its significance and harmfulness in medicine and economics and being a preponderant research model for many scientific problems. Functional gene research has been the basis for biological research in the post-genome era. RNA interference (RNAi) is a post-transcriptional gene (mRNA) silencing where endogenous or exogenous double-strand RNA specifically and efficiently suppresses the expression of a functional gene at cellular and gross levels. In view of the research value of cockroaches and the technical advantage of RNAi, this article briefly reviews the molecular mechanism of RNAi, with an emphasis on the latest research on the functional genes of B. germanica.

Objective To determine the residual spray effect of deltamethrin on German cockroach ( Blattella germanica) and the potential relationship between the kdr mutation and the resistance. Methods The resistance ratio of the two field strain B. germanica to deltamethrin was detected by residual contact (glass jar). The forced contact test was conducted to detect the residual spray effect on 3 representative panels of glass, painted wood and cement. The kdr genotype was determined by sequencing. Results The knockdown rate decreased with the increase in the surface water absorption, with the duration of efficacy shortened. The killing effect of the insecticide varied with the resistance status of different strains. The 3 panels were all able to kill the susceptible and low resistance strains effectively, but had no reliable effect on the strain with moderate resistance. Low and moderate resistant field strains that were tolerant to deltamethrin all had the kdr genotype, with the former having a relatively high frequency of heterozygosis genotype (RS), the latter relatively high in the homozygosis genotype (RR). Conclusion B. germanica resistance to deltamethrin residual spray was closely related to the kdr genotypes. Incorrect use of insecticide may result in the increase of kdr genotype frequency, so frequency and dosage need to be adjusted based on the environment types, the target resistance and the insecticide history with residual spray management combined with toxic or gel bait to achieve the ideal control effect.

Wide application of insecticides has resulted in severe resistance in the German cockroach (Blattella germanica). This study reviews the discovery and molecular and evolutional mechanisms of the knockdown resistance (kdr), also known as the sodium channel resistance, with emphasis on the molecular structure, functional research Methods of kdr mutations and up-to- date representative results. In addition, the latest findings are summarized to inform the prevention, control and resistance monitoring of the cockroaches.

Objective To analyze the epidemiological characteristics of dengue fever cases from 2006 to 2010 for determination of the risk of dengue fever outbreaks in Beijing. Methods Data of the reported dengue fever cases in Beijing were collected and analyzed for their epidemiological characteristics with SPSS software. CO₂ trapping lamp method was used to monitor the constituent ratio and density of mosquitoes. Results A total of 23 imported dengue fever cases were confirmed, of which 95.65% (22/23) of the cases were at the age of 25-59 years. The male-female ratio was 4.75∶1. Among them, 69.57% (16/ 23) were office clerks. The constituent ratio and density of Aedes albopictus showed 25.71 times and 6.00 times increase in 2010 than in 2007, respectively. Conclusion The density of subdominant mosquito species (Ae. albopictus) has increased in recent years. Vector monitoring and control measures should be implemented effectively to reduce the outbreak risk.

Objective To study the activity of Glutathione S-transferase (GSTs) of German cockroaches (Blattella germanica) at different developmental stages (from nymph to adult) and different field strains in Beijing. Methods The specific activity of GSTs and resistance levels of B. germanica were determined by spectrophotometry and contact biossay. Results The specific activity of GSTs increased gradually during the nymph period and reached the highest by week 4, which then decreased to the lowest value during eclosion. The specific activity of GSTs in susceptible strains of B. germanica was 2.70 nmol/(min·mg) with K_m of 2.26 mmol/L and V_max of 0.33 nmol/(min·mg); the specific activity of GSTs in nine field strains ranged from 2.76-8.69 nmol/(min·mg) with K_m of 0.65-2.37 mmol/L and V_max of 0.33-0.54 nmol/(min·mg) V_max. Compared with susceptible strains, field strains had higher specific activity and V_max yet lower K_m values. Field strains also demonstrated different degrees of resistance to two commonly used pesticides (cypermethrin 1.50-8.37 fold; propoxur 1.04-3.34 fold). Conclusion GST activity varied in the developmental stages from nymph to adult, which may be involved in the development of insecticide resistance in the field strains of B. germanica.

Objective To examine vector prevention and control practices for large-scale events in China by describing vector monitoring and control as a part of pest control operations (PCO) in the 2008 Beijing Olypmic Games. Methods Candidate PCO companies were first screened, and eligible bid winners were then trained and tested, during which the services provided were supervised and inspected by the government designated agency. Results The PCO companies achieved satisfying vector control rates during the 2008 Olympic Games. Conclusion A government-funded pest control model for large-scale events has been established, which utilizes well-trained PCO companies under the management, coordination and supervision of health care administrators knowledgable of technical protocols formulated by the disease prevention and control system.

Objective To identify the body and subcellular distribution of acetylcholinesterase (AChE) activities in the Blattella germanica. Methods The AChE activities in different body parts and subcells were determined. Results The AChE activities in the head, chest and abdomin of male adults were 56.9%, 19.5% and 23.6% of the total activity, respectively. The difference in activity between the three body parts was statistically significant (F＝127.96，P＜0.05), where the AChE activity in the head was significantly higher than those in the chest and abdomen (P＜0.001). The subcellular organelles in descending order of the total and specific AChE activity were: mitochondria＞microsomes＞cytoplasmic solution＞nuclei and cell debris. Conclusion AChE activities were distributed in the head, chest and abdomen of B. germanica, with the highest in the head accounting for more than 50% of the overall activity. Subcellular distribution showed the highest AChE activity distribution in the mitochondria, accounting for almost 50% of the total activity.

【Abstract】 Objective To screen resistance?related gene from the susceptible strains and field resistant strains of Blattella germanica by comparing their gene expression products. Methods Based on the known B.germanica sequence information released by NCBI database, the oligonucleotide probes were designed and synthesized. The oligonucleotide microarray was employed to analyze the expression profile of susceptible and resistant strains and differential expression genes associated with resistance were screened out. The results were confirmed by real time RT?PCR. Results Five differential expression genes were screened out, including three of up?regulated genes (fold change≥2) such as CYP6K1,  alpha?amylase mRNA and aspartic protease precursor and two of  down?regulated  genes (fold change≤0.5) like allergen Bla g 6.0101 mRNA and allergen Bla g 8 mRNA. Conclusion It is possible to screen out differential expression gene by self?made gene chip, and CYP6K1 is perhaps closely related to resistance.

【Abstract】 Objective To know about the mosquito density in Beijing city and Olympic venues by questionnaire. Methods Seven districts and seven Olympic venues were chosen to implement questionnaire survey by stratified random sampling. Results According to survey in the indoor environment, 92.31% of the respondents thought there were only a few mosquitoes in Beijing city, and 96.02% of the respondents thought there were few mosquitoes in Olympic venues. For the outdoor environment, there were 77.81% of the respondents who considered few mosquitoes in Beijing and 97.26% of the respondents considered that few mosquitoes was in the Olympic venues. About 69.85% of the respondents thought there were fewer mosquitoes in 2008 than in 2007 in Beijing. There were 80.60% of the respondents considered Olympic venues were good. Conclusion The mosquito density in both the indoor and outdoor environment in Olympic venues was lower than that in Beijing city, and the mosquito density in 2008 was lower than that in 2007.

【Abstract】 Objective To summarize the successful experience and disadvantage for Beijing Olympic Game by analyzing the integrated vector management (IVM) strategy in green homeland media village.  Methods The integrated management measure was used in this study in which the principles like “devoting main efforts into source reduction, putting chemical control first and combining physical control with environment management”. Results Random investigation showed that above 80% people selected no vectors or seldom vectors. The density of mosquito and fly declined quickly, and the average densities of them were 18.5/lamp·2 h and 29.4/cage·d, which was little higher than that in the other nuclear areas. Rodent and cockroach density was 0. Conclusion It is essential to define organization, carry out the responsibilities and eliminate the breeding site inside and outside of green homeland media village.

【Abstract】 Objective To know about West Nile virus （WNV） in mosquitoes during 2008 Beijing Olympic Games, and prevent and control West Nile fever. Methods Mosquitoes were collected by  CO2  lamp  trapping  method.  Two  methods, ADAPCO’s Ramp System and MAS’s VecTest Kits, were used to detect WNV in mosquitoes. Results Compared with 2006 and 2007, the density of main vectors decreased significantly in 2008. Culex pipiens pallens was the dominant specie of mosquito, which constituted ratio reached 96.94% in Beijing Olympic venues. There were 22 275 mosquitoes captured in Beijing Olympic venues that all were negative by detection. Conclusion Mosquitoes were controlled effectively in 2008 Olympic Games. No WNV?positive mosquitoes were detected.

       【Abstract】 Objective To predict the risk indicators of the harm caused by vectors and the occurrence of related diseases during the Olympic Games by risk recognition and assessment methods. To take response measure timely and reduce effectively the harm caused by vectors in order to prevent the occurrence and prevalence of vector?borne diseases. Methods To grade the risk by analyzing the occurrence probability and consequence of risk event comprehensively. Firstly, educe the list and confirm the classification of the risk by literature consultation, empirical analysis, brain storm and expert advice. Secondly, judge the risk level by risk assessment index matrix method and provide the standard to the risk classification. Results The vector?borne diseases and nuisance caused by vectors could be potential during the Olympic Games. For the probability of the public health event caused by vectors, it certainly happens for the biting and infestation of vectors, and probably occurs for environment disruption. It is rare for the occurrence of cables bitten by rodent and power apparatus disruption. The levels of the public health event damaged by vector are as follows: it is moderate harm for the cable bitten and electronic facility disruption, and it is slight harm for the vector biting and infestation or environment disruption. Conclusion The goal that there is no serious harmful events caused by vectors during Beijing Olympic Games would be certainly realized by scientific recognition and assessment of the risk, comprehensive surveillance of vectors, integrated control, scientific using of pesticide, the organization of emergency response team and the generalization of advanced technology.

【Abstract】 Objective To know about the population distribution and seasonal fluctuation of main vectors by the successive monitoring from 2006 to 2008 in Beijing Olympic venues, and to provide the scientific basis for vector control. Methods The CO₂ trapping lamp method was used for the surveillance of mosquitoes, baited cage trapping method for the flies, night trapping method for rats and paste catching method for cockroaches. Results Culex pipiens pallens was the dominant species of mosquito, accounting for 96.94% of the caught mosquitoes in Beijing Olympic venues. The dominant species of fly was Sarcophaginae, accounting for 46.13 % of the caught flies. Mus musculus Linnaeus was the dominant species of rats, accounting for 63.30 % of the caught rats. Blattella germanica was the dominant species of cockroaches, and all the captured cockroaches were German cockroaches. Compared with 2006 and 2007, the density of main vectors decreased significantly in 2008. During the period of the Olympic Games, the density of main vectors had been in the low level. The density of mosquito declined 88.57% and 89.26%, 69.88% and 81.63% for the fly density, 100% for the rat density and 99.98% for the cockroach density. Conclusion The density of main vectors decreased significantly during the period of Beijing Olympic Games. No serious harmful events caused by vectors occurred in Beijing 2008 Olympic Games. The goal about vector control had been realized completely.

【Abstract】 Objective To study the influence of main meteorological parameters on the mosquito density. Methods With the data of mosquito density from 2005 to 2007 provided by Beijing Center for Disease Control and Prevention and the meteorological data such as average temperature, average minimum temperature, average maximum temperature, rainfall, rainy days, sunshine time, relative humidity and average wind speed, a multiple stepwise regression would be made with statistical software SAS 9.0. Results The multiple regression co-linearity results showed there was strong linear relationship among average temperature，average minimum temperature and average minimum temperature. The multiple stepwise regression equation was y＝0.533 97X2＋0.078 14X7－2.673 29X8－2.232 56 （X2,  X7 and X8  represented average minimum temperature, relative humidity and average wind speed, respectively）. Conclusion The main meteorological parameters closely related to mosquito density were average minimum temperature, relative humidity and average wind speed. The order which affected mosquito density was in turn average minimum temperature, average wind speed and relative humidity

Objective To develop and implement effective strategies and measures of vector control in order to avoid the harmfulness caused by vectors during the Olympic Games,by analyzing the risks and challenges in vector control.Methods The risk of vector-borne diseases occurrence,nuisance and adverse impact caused by vectors was advanced by analyzing the species,density and the damage of vectors in recent years in Beijing.Control strategies were established according to the monitoring results of the vector population density,resistance and the pathogens in Olympic venues and in urban areas during 2005-2008,as well as the selection of effective control method and management measures.Results The risk of vector-borne diseases occurrence and nuisance caused by vectors existed in Beijing.It was the main control strategies for the vector control in the Olympic Games that included sound management mechanism,a comprehensive density monitoring,the scientific and rational use of pesticide,the consolidated vector control practices,and the organizing of emergency response team.Conclusion It produced the powerful technique support for the vector control of 2008 Olympic Games through the implementation of vectors monitoring and control,the development of vector control technology and the establishment of all kinds of vector control projects.No serious harmful events caused by vectors occurred during Beijing 2008 Olympic Games.

Objective To summarize successful experiences and heritage of vector control by analyzing the vector control efficacy in 2008 Beijing Olympic Games.Methods The density of vector was monitored comprehensively and systematically in the Olympic core area,Olympic venues and outside of Olympic venues.Large-scale vector control activities were carried out in the area within 2 km and the whole city,with Olympic venues as the key places of vector control.Results The density of vector in the Olympic venues and the whole city declined.The public health goal of the Olympic Games,which was "effective control for the quantity and species of vector in the area related to Olympic Games" was realized completely.Conclusion The measures and practices taken in the Olympic Games were effective.The unique experience,technology and control mechanisms were one of Olympic legacy,which would guide vector control practices in Beijing or the whole country in the future.

Objective To study the role of carboxylesterase in the development of organophosphate resistance and the activity variance of carboxylesterase in different strains of German cockroach( Blattella germanica).Methods Relationship between carboxylesterase and organophosphate resistance in German cockroach was studied with bioassay,biochemical analysis and synergistic test.The cockroaches from the susceptible strain(SS) of laboratory and field strains of different areas in Beijing [Xuanwu(XW) district,Changping(CP) district,Shunyi(SY) district and Shijingshan(SJS) district] were used as test insects. Results The synergistic test showed that synergistic ratio of TPP to malathion and dichlorvos were 1.86 and 1.51 fold in susceptible strain,respectively.And in field strains(XW,CP,SY and SJS),they were 5.79,20.08,15.26 and 4.74 fold for malathion,respectively and 2.00,1.67,2.16 and 4.81 fold for dichlorvos,respectively.There was significant difference between the Michaelis-Menten constants( K _m) and the maximum velocity( V _max) of carboxylesterase from two strains of German cockroach.The K _m and V _max of caboxylesterase in susceptible strain were 0.1580 mmol/L and 58.4225 μmol/(mg pro·min),respectively.And in field strains(XW,CP,SY and SJS),the K _m and V _max of carboxylesterase were 0.1279,0.1071,0.1080,0.1095 mmol/L and 307.2550,338.5755,340.3300,212.4570 μmol/(mg pro·min),respectively.The inhibition medium concentration(I ₅₀) of malathion and dichlorvos to caroxylesterase from SS strain were 17.64 mmol/L and 0.91 μmol/L,respectively.For field strains,the I ₅₀ of malathion were 80.48,35.49,83.24 and 82.29 mmol/L,respectively,and that of dichlorvos were 15.35,7.89,11.52 and 8.60 μmol/L respectively.The inhibition of malathion and dichlorvos to caroxylesterase from SS strain(I ₅₀ were) was much lower than from field strains strain(XW,CP,SY and SJS).Conclusion The enhancement of detoxification activity was one of resistance mechanism to organophosphate in German cockroach.

Objective To confirm the resistance status of Blattella germanica through studying its carboxylesterases(CarE) characteristics systemically and establish a quick, accurate and simple detection method. Methods The optimal concentrations of CarE and substrate, pH, temperature and reaction time of the reaction system, were determined by orthogonal matrix methods. And the optimal group was selected in the experiment. The data was analyzed with range analysis and analysis of variance. Results The results revealed that there were significant difference among various levels of the selected five factors which affected specific activity of CarE from Blattella germanica. The optimal levels of A (CarE concentration), B (substrate concentration), C (reation time), D (reation temperature) and E (pH of reation system) were A ₄ (0.35 head/ml), B ₃ (0.6 mmol/L), C ₁ (5 minutes), D ₄ (40 ℃) and E ₂ (pH 6.5), respectively. The results of range analysis and variance analysis indicated that the optimal combination was A ₄B ₃C ₁D ₄E ₂, and the maximum specific activity of CarE was 37.286 μmol/(mg pro·min) determined under the optimal conditions. The effect of factors on CarE specific activity were in the order of temperature>time>substrate>enzyme concentration>pH. Conclusion The optimal condition were: 0.35 head/ml, 0.6 mmol/L substrate, 5 mintues, 40 ℃, respectively.