Malaria is a globally prevalent vector-borne disease, causes great physical and mental suffering, with serious social and economic impacts on the world. Studies suggested that both natural and social factors have an impact on the ecology of Anopheles mosquitoes. This paper reviewed the possible impact of natural factors, such as global climate change, natural disasters, and social factors including insecticide abuse, water pollution, rapid urbanization, land reclamation, deforestation, reservoir construction,and farming practices on the ecology of Anopheles mosquitoes in order to target vector control measures and adopt robust malaria elimination strategies.

Objective To examine vectors and related disease surveillance, and improve the ability to prevent and control related infectious diseases. To integrate existing vectors-related disease surveillance and vector population density surveillance into a comprehensive monitoring mode, in order to achieve sharing and rational allocation of public health resources. Methods Four levels of comprehensive monitoring mechanisms were explored: 1) Pdisease control and prevention; 2) Municipal disease control and prevention; 3) County-level disease control and prevention; and 4) Disease control and prevention in special large- scale enterprises. Results A total of 89 Haemaphysalis longicornis, Dermacentor silvarum and Rhipicephalus sanguineus were captured during emergency monitoring. A total of 2000 Culex pipiens pallens, Cx. tritaeniorhynchus, Anopheles sinensis and Aedes albopictus were also collected. Routine comprehensive monitoring captured 42 766 mosquitoes, including 30 871 Cx. pipiens pallens, 10 211 Cx. tritaeniorhynchus, 1322 An. sinensis, 89 Ae. albopictus, and 273 other mosquito species, accounting for 72.18%, 23.88%, 3.09%, 0.21%, 0.64%, respectively. Three hundred twenty-one mice were captured at the monitoring spots with a capture rate of 2.03%, including 131 Rattus norvegicus, 118 Mus musculus, 64 R. rattus, and 8 Apodemus agrarius, accounting for 40.81%, 36.76%, 19.94% and 2.49%, respectively. R. rattus were only caught in Jiaonan. Pathogenic surveillance during emergency monitoring found two ticks positive for pathogens and no positive mosquitoes. Specimens from conventional comprehensive monitoring were sent to the national Center for Disease Control and Prevention. Conclusion A comprehensive monitoring mechanism integrating vector-borne disease surveillance and population density monitoring could achieve the sharing of epidemic information, vectors and Results of pathogen detection. This integration would have great significance to the prediction and early warming of vector-borne disease epidemics.

Objective To determine food composition and utilization of migratoryreed vole (Microtus fortis) inhabiting the Dongting Lake area during summer months. Methods The night trapping method was used to catch reed voles. Their gastric contents were analyzed using the microhistological identification to determine contents and food composition. Results Voles in the area primarily fed on leaves and stems of herbaceous plants, and occasionally seeds and bark. Their main diet consisted of Cynodon dactylon, Imperata cylindrical, and Xanthium sibiricum which accounted for 17.93%, 11.44%, 13.50% of recognizable stomach contents, respectively. Conclusion M. fortis in the Dongting Lake area fed on a variety of plants, indicating great capabilities to adapt to diverse environments.

Objective To integrate monitoring of rodents and rodent-borne diseases, and to explore and analyze the feasibility of the integrated monitoring mode. Methods An executive office was established to coordinate the related departments and staff for investigating the epidemics. Investigations included epidemiological surveys, measuring rodent density with the night trapping method, capturing live rodents using the cage-trap method and etiological detection. Results In 2010, one case of leptospirosis was reported in the county with an incidence rate of 0.25/10⁵. A total of 52 rodents were captured in 2117 traps, with a rodent to trap density of 2.46%. Etiologic and serologic detection of plague was negative. Hantaan virus antigen positive rate was 4.00% and Hantaan virus antibody positive rate was 2.67% . The leptospira culture was negative. Conclusion The integrated monitoring mode was generally feasible in Longyou. Further strengthened research on the integrated mode for both rodents and rodent-borne diseases is necessary.

Objective To compare the overall effect and cost effectiveness of different baits and bait allocation Methods for the control of the great gerbil (Rhombomys opimus). Methods From 2009 to 2010, two different baits, Carrots＋Type-C Botulinum and wheat＋Type-C Botulinum, were allocated using two deployment strategies. The strategies were poison bait boxes and lines, in the natural forest of cakcayr (Haloxylon ammodendron) distributed on Alashan desert in Inner Mongolia of China. Results The number of effective burrows forR. opimus in autumn was significantly higher than that in spring in those two years. The control effect on different bait and allocation Methods of baits toR. opimus showed that deratization effect of poison baits box＋ carrots＋Type-C Botulinum, which averaged to 91.26%, was the highest, but its cost efficiency was the lowest (36.51 yuan/hm²). Deratization effect was different in different seasons. Although the average deratization effect (77.33%) in spring was higher than that in autumn (71.11%), the difference between the two seasons was not significant. Conclusion The deratization effect of poison baits box＋ carrots＋Type-C Botulinum was most pronounced, but its cost efficiency was lowest. This method is more cost effective and could be more applicable for control ofR. opimus.

Objective To identify efficacy of pyrethroid aerosol insecticides in killing Culex pipiens pallens, Musca domestica and Blattella germanica. Methods KT₅₀ is one of four kinds of aerosol insecticides on three types of insects were tested according to GB/T 13917.2－2009 in hermetic round canister. Killing efficacy in simulated fields was tested according to GB/T 13917.10－2009. Results The KT₅₀ values of four kinds of aerosol insecticides were less than 2 minutes for Cx. pipiens pallens and M. domestica, and less than 1 minute for B. germanica. The 24 h-mortality of insects used in the hermetic round canister was 100%. The one -hour killing efficacy of the four aerosol insecticides in simulated fields for Cx. pipiens pallens, M. domestica and B. germanica was 100%. Conclusion The four aerosol insecticides all showed fast killing effects for Cx. pipiens pallens, M. domestica and B. germanica.

Objective To establish a rapid, sensitive and specific detection method for detecting Chikungunya virus(CHIKV) using Real-time fluorescence quantitative PCR. Methods With specifically designed primers and a TaqMan probe on the highly conserved sequence of CHIKV through alignment, the sensitivity of the Real-time fluorescence quantitative PCR assay was optimized by evaluating different concentrations of primers and probes. Results A specific Real - time PCR method was developed with the sensitivity of 21 copies/μl for CHIKV, a synthetic CHIKV genome DNA as a positive control; Japanese encephalitis virus, Yellow fever virus, Dengue virus were using to examine the specificity. Conclusion Promising prospects of this assay could be expected for Chikungunya fever prevention and control.

Objective To investigate the species composition, ecological habitats and the natural infection of the dengue vectors in Menglian and Lancang counties bordered with Myanmar in Yunnan province, so as to provide evidence for the prevention and control of dengue fever. Methods Three villages in Menglian and Lancang counties were selected as surveillance sites. Adult mosquitoes were captured by human-landing catches and Aedes mosquito larvae were collected from various types of indoor and outdoor water containers in the three surveillance sites. Dengue virus in mosquitoes was detected by RT-PCR. Results A total of 3436 individual adult female mosquitoes of 22 species from 8 subgenus in 6 genus were collected from three sites in Menglian and Lancang counties from June to October, 2010. Aedes albopictus was the predominant species in three sites, accounting for 33.82% of all captured mosquitoes. No Ae. aegypti mosquitoes were found in these field sites. The average house index (HI), container index (CI), breteau index (BI), and thousand-person index of Ae. albopictus was 19.3, 5.84, 30.3, and 68.5 respectively. The dominant Ae. albopictus breeding environments were thick bamboo tubes, amphora, and used tires, accounting for 34.1%, 27.5% and 17.6%, of positive water containers, respectively. The average population density of Ae. albopictus adults was 8.98 per person per hour. The density peaked in July and August. Dengue virus was not identified by RT-PCR from 29 batches of Ae. albopictus. Conclusion Local dengue fever surveillance should be strengthened due to high vector density and wide distribution of Ae. albopictus in these areas.

Objective To identify Anopheles sinensis population density, growth trends and insecticide sensitivity. Methods Anopheles mosquitoes were collected by human landing catch and collecting mosquitoes inside cowsheds during endemic season. The WHO insecticide-susceptibility test was used. The rate of knockdown was calculated after 10, 15, 20, 30, 40, 50, 60 minutes after exposure. The mortality was scored 24 hours after exposure. Results From late June to early October in 2008, 322 An. sinensis were collected by human landing catch in bed nets semi-overnight. The biting rate was 1.61 bites per person per hour. A total of 886 An. sinensis were captured in cowsheds. The density was 147.66 mosquitoes per person per hour. The resistance of An. sinensis to deltamethrin and cyfluthrin were levels R and M, respectively. From late June to early October in 2009, 349 An. sinensis were caught in bed nets semi-overnight. The biting rate was 1.25 bites per person per hour. With 652 An. sinensis collected, the density was 108.67 mosquitoes per person per hour. The resistance of An. sinensis to deltamethrin and malathion were levels R and R, respectively. Conclusion An. sinesis is resistant to deltamethrin and initially resistance to cyfluthrin in Jiangsu province. The applied insecticide should be chosen when there is outbreak of malaria by using insecticide treated nets (ITNs) and indoor spraying of insecticide. Health education should be introduced to local people to improve protection from mosquitoes and minimize contact with mosquitoes.

Objective To observe the life cycle of Xenopsylla skrjabini under laboratory conditions. Methods Meriones meridianus was served as blood-supplying animal under the conditions of (26±0.5)℃ and 70%±5% RH with routine breeding and plate culture. Results The entire life cycle of holometabolic X. skrjabini could be divided into 4 stages (egg, larva, pupa/cocoon and adult). The development periods (egg-larva, larva-pupa, pupa-adult and egg-adult ) were 5.65±0.49 d, 10.78±0.67 d, 7.52±0.95 d, and 23.96±1.49 d for the male, respectively; 5.49±0.51 d, 10.20±0.78 d, 4.90±1.04 d and 20.59±1.14 d for the female, respectively. The hatching rate (egg-larva), pupation rate (larva-pupa), emergence rate (pupa-adult) and growth rate were 91.0%, 85.7%, 82.1% and 64.0%, respectively. The sex ratio after emergence was 1.8∶1. The longevities were 4.17±1.11 d for the male and 5.31±1.69 d for the female under starvation, 13.56±2.56 d for the male and 20.50±8.31 d for the female under supplying blood. The average number of laying eggs per day (15 males and 10 females as a unit) was 23.46, and the average lifetime number was 624.00±5.76. The non-linear regression equation between the average daily number of laying eggs (n) and oviposition time (d) was y＝e^{［4.548－ 0.140(x － 2)］}(x≥3). Conclusion The short life cycle and high productivity of X. skrjabini were in the favor of transmission and prevalence of animal plague.

Objective To identify an intestinal bacterium BGI-17 isolated from German cockroaches (Blattella germanica) and to study its activity of anti-pathogenic fungi so as to clarify the composition and relationship of the intestinal flora in B. germanica. Methods The strain BGI-17 was identified according to the morphology and physiological and biochemical characteristics, and the phylogenetic tree was generated based on the sequence of 16S rDNA for molecular identification. The test for anti-Beauveria bassiana was conducted using the plate inhibition method and the growth of fungi was observed. Results The short, rod-shaped BGI-17 was positive for flagellum, Gram stain, spore stain and catalase. The 16S rDNA sequencing of BGI-17 showed that it shared 99% similarity with the published sequence of Bacillus atrophaeus strain, and both sequences constituted a branch in phylogenetic tree. The BGI-17 inhibited the growth of B. bassiana obviously and the fungal mycelium showed sick vacuolar enlargement, leading to leakage and mycelia protoplast rupture. Conclusion The BGI-17 was B.atrophaeus and it showed strong anti-insect pathogenic fungal activity that might contribute to withstanding the infection of pathogenic fungi.

Objective To investigate the effect of Musca domestica larva antimicrobial peptides on the cell membrane of tumor cells K562. Methods Antimicrobial peptides of M. domestica larvae with inhibition activity to K562 were sieved, through some processes that induced by acupuncture with Escherichia coli induction, isolated and purified by trituration, centrifuga1ization, solid phase extraction (SPE) and reversed-phase high-performance liquid chromatography (RP-HPLC), detected activity by MTT colorimetric method and observed light microscope. After treatment with different concentrations of peaks 5 and 8, the viability, morphological changes, morphological changes, membrane fluorescein leakage and destruction of K562 cells were detected by trypan blue excluding test, optical microscope and fluorescence microscope, spectrofluorophotometer, laser confocal microscope (LSCM), respectively. Results Low concentrations (＜50 μ g/ml) of M. domestica antimicrobial peptides resulted in intact viability, little change of cellular structure, a little of fluorescein leakage [(18.95±0.05)-(22.49±0.68)] and few destruction in K562 cells; however, high concentrations (≥50 μg/ml) of M. domestica antimicrobial peptides induced lower viability, cellular form change increased gradually, a great deal of fluoresceinleakage [(62.77±4.08)-(70.81±0.18)], even macromolecular fluorescent element Dextran-FITC could leak through. Conclusion There is a concentration threshold of M. domestica larvae antimicrobial peptides on K562 cell membrane. Low concentrations of M. domestica larvae antimicrobial peptides can cause the membrane leakage increasing of cell membrane, high concentrations can lead to severe damage of cell membrane, respectively. The antimicrobial peptides inhibit the growth of K562 cells through directly killing the cells, and the mechanism is that firstly damage the membrane function, then may expand the holes or inhibit the growth by other ways after entering the cells.

Objective To determine the population number and species diversity of Calyptratae flies in Dengfeng Zhongyue Temple scenic spots of Henan province. Methods The biological diversity in the region was studied based on entomological classification principles using relevant approaches. Results A total of 23 species, 14 genus, 8 subfamilies and 5 families of Calyptratae flies were investigated in this region. The Calliphoridae were found to share the highest diversity. Ten species, 6 genus, and 3 subfamilies of flies were investigated,and the species accounted for 43.48% of all captured species around the scenic spots. The diversity indices were obvious different between the Results generated in August, September and October. The highest number of flies was present in September with however the lowest Simpson index, Shannon-Wiener index and Pielou index and highest dominance index. No difference was found in the diversity indices between August and October. Conclusion The Calyptratae flies had relatively rich species diversity in Dengfeng Zhongyue Temple scenic spots of Henan province. The Results provided fundamental data for fly prevention and control in the region.

Objective To evaluate the influence of different proteins and amino acids on the oviposition behavior of gravid female Culex pipiens pallens and Aedes albopictus under laboratory conditions, providing theoretical basis for the development of a highly effective ovitrap. Methods The oviposition preference of gravid female Cx. pipiens pallens and Ae. albopictus to different concentrations of protein and amino acid solutions was determined under laboratory settings. Results The gravid female Cx. pipiens pallens preferred to lay eggs in fish peptone solutions of 1000 mg/L and 100 mg/L and in yeast extraction solution of 1000 mg/L; the gravid female Ae. albopictus only preferred to lay eggs in fish peptone solution of 10 mg/L. Phenylalanine solutions of 1000, 100 and 10 mg/L could produce a significant oviposition preference for both Cx. pipiens pallens and Ae. albopictus. Conclusion Gravid Cx. pipiens pallens and Ae. albopictus have a high oviposition preference to fish peptone and phenylalanine.

Objective To provided evidence for the development of Japanese encephalitis (JE) control and prevention strategies by analysis of the epidemiological characteristics and the relationship between JE and mosquitoes. Methods During 2001-2010, JE cases were collected from the passive surveillance. At the same time, the acute encephalitis and meningitis symptom surveillance were conducted to identify JE cases from the perspective observational study during 2007-2010. Participating facilities included one children hospital, three provincial general hospitals and three rural county-level general hospitals in five county districts with random assignment. ELISA was used to detect the agent in blood and cerebrospinal fluid (CSF). The mosquito specimens were collected with labor hour method from May to October. Results There were 75 JE cases reported in Shijiazhuang. The annual average incidence rate and the fatality rate were 0.08/105 and 0.26%, respectively. Two peaks in age distribution were observed: one with children of 5-15 years, and the other with adults of 40 years and older. The inhabitant to floating population ratio was 2.57∶1. The time distribution was mainly in August, September and October. Culex pipiens pallens and Cx. tritaeniorhynchus were the dominant species. Correlation was found between JE epidemic and mosquitoes density (r_s＝0.5506, P＝0.000). The ratio of JE diagnosed was 28.95% among the first visiting patients. Conclusion JE epidemiological characteristics are changing with a gradually increasing incidence and increasing cases among floating population. It is important to enhance epidemiology and pathogen surveillance with acute encephalitis and meningitis for JE prevention and control. The preventive strategy for JE should be a comprehensive system based on vaccines immunization.

Objective To determine the population composition, density and distribution of vectors in Yulin urban area, providing evidence for control of these insects. Methods Human baited net trap method and lamp baited trap method were employed for mosquito collection, cage-trapping for fly collection and sticky-paste for cockroach collection. Results Mosquitoes caught belonged to 5 species 4 genera, with Culex pipiens pallens being the dominant species. The average density based on the human baited net trap method was 19.11 per net per hour, or 1.61 per lamp per hour based on lamp baited trap method. The density in the urban area was higher than that in the villages. Flies belonged 23 species 19 genera 5 family, and the common species were Chrysomya megacephala, Lucilia sericata, Musca domestica, Muscina stabulans, Boettcherisca peregrine and L. cuprina, accounting for 36.49%, 20.41%, 14.78%, 10.61%, 8.65% and 2.61%, respectively. The average density was 4.42/ cage, the highest density observed in the farm produce markets. Cockroach density was 16.28/piece·night, highest observed in the restaurants, with Blattella germanica being the predominant species. The peak of flies and cockroaches was in August, and that of mosquitoes in July. Conclusion The population composition, density and distribution of vectors were basically grasped. Integrated measures should be taken with focus on such major areas as restaurants, farm produce markets and residential areas.

Objective To identify the species, number and landing height of wintering mosquitoes in Yongcheng city, Henan province, China, so as to provide evidence for the development of vector control strategies. Methods Two residential blocks in urban and suburb areas were selected as surveillance sites. The number of mosquitoes was determined through visual observation, which was then adjusted with data from indoor settings using the labor hour method. Results All landing mosquitoes from the surveillance sites mentioned above were Culex pipiens pallens. The mosquito number differed across floors. Most of mosquitoes were on the first floor, and the number declined with the increasing of height. Conclusion Mosquitoes in residential areas of Yongcheng might come from the external environment. Physical isolation might have a good effect in avoiding mosquito bites. Chemical method should be used as the primary option for mosquito control on the first floor.

Objective To evaluate the lethal efficacy and effective duration of insecticides against Culex pipiens pallens larvae. Methods The control efficacies of the four insecticides against mosquito larvae were measured under laboratory settings and the duration tested in an artificial field. Results Temephos and Imidacloprid had good killing effects on the mosquito larvae. The efficiency of Temephos lasted 21-28 days, while that of Imidacloprid lasted 14-21 days. Ethofenprox demonstrated the worst effect. The mortality for mosquito larvae was 21.8% by day 35. Despite a low death activity, Pyriproxyfen effectively prevented the eclosion of mosquito larvae, the action of which lasted for more than 35 days. Conclusion In terms of both the labor costs and control efficacy, Pyriproxyfen is the optimal option among the four insecticides.

Objective To identify the sensibility and lethal effect of Blattella germanica on acephate, propoxur, cyhalothrin, beta-cypermethrin and fipronil in the railway region of Gansu province. Methods The pesticide smeared jam bottle drug membrane contact method advocated by WHO was used in this study. Results The resistance coefficients of B. germanica from Lanzhou and Jiayuguan railway region were 2.17 and 12.34 to beta-cypermethrin and 2.87 and 4.96 to clocythrin, respectively. The killing effects of clocythrin and propoxur on B. germanica from Lanzhou railway region were 90.00% and 53.33% , respectively, and 40.00% against those from the Jiayuguan railway region. Conclusion The usage amount of beta-cypermethrin and clocythrin should be reduced and care given to the usage of propoxur. Priority should be given to the usage of acephate and fipronil alternately so as to delay and reduce the resistance among cockroaches.

Objective To identify the resistance of Culex pipiens pallens to five commonly used insecticides in Xianyang city so as to provide evidence for control strategy development. Methods The mortality of larvae exposed to five insecticides was determined by the distinguishing dosage method. Results The resistance level of Cx. pipiens pallens was high under the diagnosis dose to DDT, DDVP, permethrin, and deltamethrin, and the mortality in 24 hours was 23.45%, 14.02%, 28.77%, 25.00%, respectively. The resistance to cypermethrin was moderate and the mortality was 58.63%. Conclusion The resistance of Cx. pipiens pallens to five commonly used insecticides in Xianyang has reached middle to high levels. Different kinds of insecticides should be used for control of mosquitoes.

Objective To analyze the epidemiological characteristics of typhus in Henan province from 2004 to 2010, in order to provide evidence for developing typhus prevention and control strategies. Methods Descriptive epidemiological method and circular distribution method were used to analyze the surveillance data of typhus in Henan province from 2004 to 2010. Results In all 172 cases were reported from 2004 to 2010. The cumulative incidence rate was 0.1822 per 10⁵. The lowest and highest incidence rates were 0.0116 per 10⁵ in 2010 and 0.0385 per 10⁵ in 2008, respectively. There were significant differences for the incidence of typhus among different years (χ²＝17.71, P＜0.05). The cases were mainly sporadic. There were no outbreaks and deaths. Most cases were distributed in central and northern areas of Henan province. The peak epidemic period was from July to September. Most cases were farmers and students. Conclusion The cases of typhus in Henan were mainly sporadic. Comprehensive prevention and control measures such as killing mice, fleas, lice, improving environmental health and monitoring host animals should be taken to control typhus effectively.

Objective To determine the killing effects of sulfuryl fluoride fumigation in ships with rodent infestation. Methods The rodent density was investigated using the Methods of observation and glue rat boards. Sulfuryl fluoride fumigating at 56 g/m³ was then administered in the obturated space of the infested ships for 10 h. Results A large number of rat feces were detected in kitchens, dining - rooms and food storehouses. Rat trace was evident, and 7 roof rats were observed on 10 glue rat boards, indicating heavy infestation. After treatment, 16 dead roof rats and 8 albino rats were found. Conclusion Rodent control in ship should be taken by fumigation of sulfuryl fluoride in emergency situation, such as heavy infestation and out break of specific diseases associated with commensal rodents.

Mosquitoes (Culicidae) are among the best known groups of insects because of their importance to man as pests and vectors of some of the most distressing human diseases, such as malaria, filariasia, Japanese encephalitis and dengue fever. Research on mosquito fauna and diversity is fundamental for further studies of the relationship between the vector and related diseases. Yunnan province has given birth to a rich and unique mosquito fauna due to its nature diversity and complex geographical condition. Up to now, there are 296 species (subspecies), 20 genera belonging to 3 subfamily of Culicidae in Yunnan province, which takes up 75% and 95% of the known species and genera in China, respectively. This region is considered as the centre of the fauna and diversity of mosquitoes (Culicidae) in China. This review involves the up-to-date research on classification, distribution, diversity for the Yunnan mosquito fauna, and present discussing on the relationship between mosquito fauna, biodiversity and environmental factors, following with a perspective study on Culicidae.

West Nile virus (WNV) is a positive, single strand RNA virus belonging to Flavivridae that causes infectious West Nile fever (WNF) in human beings. Birds are the main host of WNV, and mosquitoes the main transmitting vector. WNF has been endemic in the Europe and middle-west Asia for decades. The outbreak of WNF in the United States in 1999 and subsequent epidemics in North America in the following years have caused great concerns. Moreover, greater concerns have arisen from other transmitting routes besides mosquito bites, such as blood transfusion, organ transplantation and vertical transmission. As there is no vaccine available for prevention of WNF, the condition is associated with significant threat to public health and life security due to the high infection rate, the increasing number of severe cases and high mortality rate. This paper unfolds a comprehensive discussion about the etiology, epidemiology clinical, lab diagnosis, prevention and surveillance of WNF.

Objective To investigate the susceptibility and resistance of larvae and adult of Culex tritaeniorhynchus in Licheng district, Shandong province to the commonly used insecticides, providing the basis for chemical control of the insects. Methods A large number of adult Cx. tritaeniorhynchus were collected outdoors in the peak seasons. The first filial generation of larvae was obtained by feeding the collected adults with blood from mice. The larvae obtained and the adult female mosquitoes, which had been captured in the field and had laid the first eggs in the lab, were used as test insects. The susceptibility of the adult and larvae to commonly used insecticides were determined with the drug membrane contact method and the impregnation method respectively, as the WHO protocol, with the knockdown rate and mortality of the adult mosquitoes and the LC₅₀ (95%CI) for the larvae calculated and their resistance levels to commonly used insecticides compared. Results The mortality of the adult exposed to 0.05% deltamethrin (contact for 1 h), 0.05% beta-cypermethrin (1 h), 0.25% permethrin (3 h), 0.45% permethrin (3 h), 0.05% cypermethrin (1 h), 0.45% tetramethrin (1 h), 1% fenitrothion (2 h), 0.1% propoxur (2 h) and 4%DDT (4 h) beyond 24 h were 85.0%, 74.6%, 38.0%, 92.9%, 36.2%, 43.6%, 16.1%, 16.9% and 36.4%, respectively. The LC₅₀ and the corresponding 95%CI of deltamethrin, beta-cypermethrin, and permethrin for Cx. tritaeniorhynchus larvae were 0.0046 (0.0037-0.0055), 0.0113 (0.0092-0.0136), 0.0325 (0.0289-0.0369) mg/L, respectively; the LC₅₀ (95%CI) of dichlorvos, temephos, fenitrothion and malathion and BPMC were 4.9047 (3.8612-6.4215), 9.5733 (7.4644-12.5296), 1.2694 (1.0280-1.5055), 0.7750 (0.6060-0.9842) and 4.4237 (3.7406-5.2769) mg/L, respectively. Compared to the susceptible strains reported in previous literature, the resistance coefficients of the larvae of Cx. tritaeniorhynchus were 11.5, 1.9 and 8.8 to deltamethrin, beta-cypermethrin and permethrin, respectively, and 76.6, 7977.8, 256.4 and 84.2 to dichlorvos, temephos, fenitrothion and malathion, respectively. Conclusion Adult Cx. tritaeniorhynchus in Licheng district has developed resistance to the commonly used insecticides, with a very high resistance seen to organophosphate and carbamate pesticides in the adult. The resistance of larvae to temephos is highest among the organophosphates.

Objective To learn the distribution of arboviruses in mosquitoes in Liaoning province. Methods The samples were collected in Dandong and Jinzhou of Liaoning province in 2008. The isolation of viruses was conducted by way of C6/36 and BHK-21 cell culture, with identification of viruses done by serological, molecular and bioinformatics methods. Results A total of 9296 mosquitoes consisting of 5 species from the Culex, Aedes and Anopheles genera were trapped. Four virus isolates were obtained from pooled mosquitoes and were identified as Japanese encephalitis virus (JEV) (from Cx. tritaeniorhynchus), Banna virus (2 isolate from An. sinensis) and the mixture of Liaoning virus and Banna virus (from An. sinensis). Genotype of JEV isolate belonged to genotypeⅠ and no mutation of amino acid sequence coding conformational epitope occurred in Envelop protein. Conclusion GenotypeⅠ JEV was isolated again in Liaoning province and Liaoning virus was documented in this area for the first time.

Objective To investigate resistance of Anopheles sinensis to deltamethrin and its association with the kdr gene mutation in Yunnan province and parts of Henan province. Methods The An. sinensis samples were collected from Yuanyang and Mengla of Yunnan province and Tongbai, Huaibin and Yongcheng of Henan province in July and August of 2010. The standard WHO deltamethrin resistance bioassay was used to evaluate the resistance of the insects to deltamethrin by the knockdown rate and the mortality of them, and the genotype at the site 1014 Leu-Phe mutation in the kdr associated sodium channel gene was detected by polymerase chain reaction and sequencing. Results The results showed that the mortalities of An. sinensis in all the 5 regions were all lower than 98%, with death rate of less than 80% in Huaibin, Yongcheng, Tongbai and Yuanyang, where the populations were resistant. Also, elementary resistance was seen in Mengla county where the mortality was between 80%-97%. The kdr mutation was found through sequence analysis of the PCR products in the Huaibin, Yongcheng and Tongbai populations with no kdr mutation observed in the Mengla and Yuanyang populations. Conclusion There is a correlation between kdr mutation and the deltamethrin resistant phenotype in the Yongcheng and Tongbai populations, but no such a correlation has been found in the Huaibin, Mengla and Yuanyang populations.

Objective To study the geographical distribution of population density of Anopheles minimus and molecular identification of the species since the 20th century in Guangxi Zhuang Autonomous Region for providing scientific data for its prevention and control. Methods Data on An. minimus and malaria incidence from 1950s to 1990s in Guangxi were collected, with the adult An. minimus collected in 2004 to 2010 in the Autonomous Region in the malaria endemic areas at different longitude and latitude where An. minimus was previously the major vector and the collected samples identified by morphology and PCR assay. Results It was found that of all of the 92 counties of the Region, there were 56 counties at different longitude and latitude locations in which An. minimus existed from 1957 to 1998. An. minimus were collected in the villages of 36 counties from 2004 and 2007 where the insects were prevalent. Only 244 An. minimus were collected at the 40 surveillance sites of 20 counties, and PCR molecular identification of the species revealed that An. minimus from Wangdian village, Baise district was of An. minimus A. The insects collected from other sites were all of An. minimus C. The incidence of malaria in all the counties of the Region was reduced to 0.1/10 000 after 2008. Conclusion Currently there exist two species of An. minimus in Guangxi, with An. minimus C being the predominant species and An. minimus A about to die away. There is a substantial decrease in the population density and geographical distribution range of An. minimus in Guangxi. It is likely that An. minimus will no longer be the major vector for malaria in the region.

Objective To observe the trap effects of several different physical and chemical attractants on adult Culex pipiens quinquefasciatus, providing better designs of new mosquito trap devices. Methods The“Y”-tube olfactometer was used to measure the trap effects of seven chemicals (urea, lactic acid, glycerol, dodecanoic acid, tetradecanoic acid, hexadecanoic acid and nonyl aldehyde) and two physical attractants (sound and visible light) on adult Cx. pipiens quinquefasciatus. The number of individuals attracted by the tested attractants was calculated and compared among the groups. Results Chemical attractants including urea (10 mg/L), lactic acid (1000 mg/L), hexadecanoic acid (10 mg/L), nonyl aldehyde (0.1 mg/L) and physical attractants including 150 Hz sinus tone and 380 nm visible light had better mosquito trap effects. Conclusion The chemical and physical attractants mentioned above can be introduced to the design of mosquito trap devices to improve the efficiency of mosquito control.

Objective To develop a highly specific and sensitive Real-time PCR assay to detect Orientia tsutsugamushi. Methods A pair of primers and a TaqMan-MGB probe were designed according to the 56 kD outer membrane gene sequence. Results A linear relationship between the threshold cycle (Ct) of the quantitative Real-time PCR and the DNA copy number was demonstrated (r=0.99). The standard curve showed that 26 copies target genes per reaction could be detected by this method. The lowest detection limit of this method was 2 copies per μl. The method showed high species specificity and good reproducibility. Conclusion These results suggested that the Real-time PCR with TaqMan-MGB assay is highly specific and sensitive for the detection of O. tsutsugamushi, which might be applied for the diagnosis of this infection.

Objective To investigate the infection rate of ticks with Anaplasma phagocytophilum in in the Northeast China forest region. Methods In 2010 and 2011, bulk ticks were collected by flagging vegetation of grassland or woodland from the Northeast China forest region. 16S rRNA and gltA gene fragment of A. phagocytophilum in ticks were amplified with PCR, followed by sequence analysis and comparison with the corresponding parts of the sequences deposited in GenBank. Results As a whole, a total of 2293 ticks were tested, including 1161 in 2010 and 1132 in 2011, with the positive rates of A. phagocytophilum being 4.91% and 4.24%, respectively. The positive rates of Ixodes persulcatus, Haemaphysalis longicornis and Dermacentor silvarum were 4.86% (91/1872), 3.41% (14/411) and 0 (0/10) with no significant difference among them. The sequence of NE-gltA-1 had the highest similarity to that of Hc346(GenBank:GU935788) and so was NE-gltA-2 and MDJ-Ip92 (HQ396224), with their homology with ZJ-HGA-72(DQ458811) amounting to 84%. The similarities of 16S rRNA gene with that of China-C-Tt (GQ412339) and Florida (AF309867) were 99% and 97%, respectively. Conclusion It is concluded that there exists the infection of ticks with A. phagocytophilum in the Northeast China forest region, and I. persulcatus and H. longicornis may be involved in the maintenance and transmission of A. phagocytophilum.

Objective To understand the temperature and photoperiod response model of Blattella germanica, and the effect of temperature and photoperiod on their growth and development, reproduction and life cycle rhythm, providing a theoretical basis for the development of effective control strategies. Methods Tests were done in an environmental test chamber. Five temperature gradients at 16, 18, 22, 26 and 30 ℃ were set in the light cycle of LD12 h:12 h (light intensity of 4000 lx), and the photoperiod LD16 h:8 h, LD12 h:12 h, LD8 h:16 h and LD0:24 h set at 26 ℃. Results It was found that in a constant photoperiod (LD12 h:12 h) the nymph stage development rate corresponded with the following temperature gradients 30 ℃> 26 ℃>22 ℃>18 ℃>16 ℃, and the nymph emergence rate decreased with the lowering of the temperature. Also, the nymph stage development rate corresponded to the following photoperiod LD16 h:8 h>LD12 h:12 h>LD8 h:16 h>LD0:24 h at a constant temperate of 26 ℃, with the nymph emergence rate decreasing with the reduction in irradiation time. Conclusion The photoperiod response model of B. germanica is of photoperiodic long-day type. The nymph stage is important in the life cycle of B. germanica. The impact of temperature and photoperiod interaction on B. germanica results in the occurrence of diapause, impairing its development period, emergence and reproduction, and thus life cycle rhythm.

Objective To observe the effect of anti-tumor peptide from Musca domestica larvae on the nucleus, the mitochondrial membrane potential and apoptosis protein cysteinyl aspartic proteinase-3 (caspase-3), and apoptosis of K562 cells. Methods Hoechst33258 fluorescent staining was used to observe the fluorescence intensity under a fluorescence microscope. The peak 5 and 8 components from M. domestica larvae were incubated with the K562 cells and the fluorescence intensity of the K562 cell nuclei was detected. The fluorescent probe rhodamine 123 was used to label the cells, which were observed under LSCM (laser scanning confocal microscope, LSCM) for the intracellular fluorescence intensity of the dye that reflected the mitochondrial membrane potential. And caspase-3 immuosorbent test kit and microplate were used to detect the enzyme activity of caspase-3 in K562 cells. Results It was found that the peak 5 and 8 components from M. domestica larvae, after incubation with the K562 cells, increased the fluorescence intensity of some K562 nuclei, suggesting the occurrence of apoptosis of K562 cells. The fluorescence intensity of the K562 cells incubated with the peak 5 and 8 components from M. domestica larvae and labeled with rhodamine 123 was significantly lower than that of the cells in the control group (t₁=21.30, t₂=196.23, P<0.05), which indicated that the anti-tumor peptide was able to reduce the mitochondrial membrane potential of K562 cells. Also, the content of caspase-3 in the cells in the test group was significantly higher than that in the cells in the control group(t₁=146.92, t₂= 189.56, P<0.05), which suggested that the antitumor peptide could contribute to apoptosis of the K562 cells. Conclusion The anti-tumor peptides in peak 5 and 8 components can damage the cell nucleus, leading to apoptosis of K562 by reducing the mitochondrial membrane potential, activating the caspase-3, and interfering with the physiological function of the cells.

Objective To study the resistance of Culex pipiens pallens and Musca domestica to insecticides in Tianjin in order to provide the basis for better use of insecticides. Methods Six districts(counties) of Tianjin were selected as the surveillance sites. The resistance of mosquitoes to insecticides was evaluated by dipping method, with the topical application method used for the detection of the resistance of houseflies. Results It was found that Cx. pipiens pallens and M. domestica in Tianjin were resistant to insecticides to a certain extent. The mean relative resistance of Cx. pipiens pallens to DDVP, deltaMethri, β-Cypermethrin, parathion and fenobucarb were 61.49, 13.08, 3.72, 5.03 and 17.84, respectively, and that of M. domestica to DDVP, β-Cypermethrin, deltamethri, propoxur and permethin were 9.49, 58.44, 11.24, 2.66 and 2.95, respectively. Conclusion The resistance of Cx. pipiens pallens and M. domestica to different insecticides varies and the surveillance results should be a guidance for the reasonable use of the insecticides for better control of the insects.

Objective To observe the role of ecological approaches to deratization in keeping the rat density in large hotels as low as possible, providing a scientific basis for future deratization. Methods First, 0.005% bromadiolone corn poison bait was laid out for 6 consecutive days in the four large hotels with similar environmental conditions and serious rodent damage. And then the 4 hotels were randomly divided into two groups, of which ecological approaches to deratization were followed in one, with the other used as the control group. S-100 method was used to evaluate the deratization effect by the deratization rate based on the difference in the rodent density between the 2 groups within 6 months. Results The deratization rate of 0.005% bromadiolone corn poison bait for the 4 hotels was 96.92%, 97.06%, 96.82% and 97.53%, respectively, with the overall deratization rate being 97.12% within the 6 months. By the end of the observation, the rat density of the 2 hotels in the test group increased only by 2.97 compared with that at the time when corn poison bait deratization was completed, while the density of the 2 hotels in the control group increased by 34.34 in the same period of time with a difference of 31.37 between the two groups(u=22.24, P<0.01). Conclusion The deratization effect with poison bait followed by ecological approaches is a highly effective means for safe deratization and prolonged maintenance of the state.

Objective To validate the biological function of Hk2,which is reported to be in combination with the cognate response regulator Rrp2 to constitute a two component signal system in Borrelia burgdorferi that controls the key virulence factors required for pathogen invasion in mammals. Methods A hk2 knockout strain (hk2^-) was generated through homologous recombination, with the biological function of Hk2 estimated by the mouse-tick animal model. Results The hk2^- knockout strain remained to be able to infect mouse by needle inoculation, and subsequently successfully detected in the midgut of fed-larvae and -nymph by IFA. The quantitative-PCR demonstrated that hk2 knockout had no influence on bacterial replication in the midgut of fed nymph. However, only 50% of tested mice were infected in hk2^- group by tick bite. Conclusion The hk2 knockout does not affect the pathogen acquisition from mouse by larvae ticks and subsequent persistent colonization in tick midgut, but it embarrasses the transmission from nymph to mouse under natural conditions by tick bite. The above data indicate that the Hk2 may effectively contribute to the pathogen invading mammals in the life cycle of B. burgdorferi.

Objective To identify Borrelia burgdorferi sensu lato infection of rodents in Pan’an county, Zhejiang province. Methods The ospA gene specific fragments from 128 mouse liver and spleen samples were detected using the PCR method and the positive samples were sequenced, followed by phylogenetic analysis. Results It was found that there were four ospA gene positive fragments out of the 128 samples, of which 3 fragments were obtained from Rattus losea and the other one was from Apodemus peninsulae. The 4 positive fragments shared high similarity with each other in terms of the sequences and shared high identities with B. valaisiana. Conclusion B. burgdorferi sensu lato can be detected from samples using the ospA gene. There exists B. burgdorfer sensu lato infection in rodents in some mountain areas of Zhejiang province, and B. valaisiana is found to be predominant.

Objective To establish a mce gene-based PCR detection method for the analysis of mce gene conservation of Leptospira interrogans and its bioinformatics. Methods The NCBI/Blast and NCBI/Cds online database was used for the search of the conserved functional domain in the mce gene and its specificity, with TMHMM Server-2.0 employed for the prediction of the transmernbrane regions of the encoded protein. The segments of entire mce gene from L. interrogans strain lai were amplified by PCR and then sequenced, with the sequence of cloned mce gene compared with the reported sequence of mce gene (GenBank accession No.: NP_712236) by DNAStar. The genome DNAs from the 13 prevalent strains of L. interrogans in China were used as the templates for the validation of the mce gene-based PCR detection method. A comparative analysis of the amplified mce gene products from different strains was also accomplished based on their sequences and a phylogenetic tree was generated from the presumed sequences of amino acids. Results The results of bioinformatic analysis showed that there was a mce super family conservation functional domain that was associated with adhesion and invasion of pathogens in the mce gene from L. interrogans. It was clear that there was a L. interrogans transmembrane structure in mce. High homology sequences of mce gene were present in L. interrogans, with the similarities of nucleotide sequences of mce gene from different L. interrogans strains more than 95%. Conclusion The mce gene with conservation specifically exists in different pathogenic L. interrogans strains, and it has a transmembrane structure and a super family functional domain that is associated with L. interrogans adhering to and invading their host cells.