ISSN 1003-8280 CN 10-1522/R 中国疾病预防控制中心 主办
With the development of public health pesticides and registration management, public, resident personal protective products play more important roles in public health pest control, promoting livable environments, population health and well-being in China. The authors reviewed the development and application of public health pesticides in China from 2013 to 2016.
Objective To investigate the bacterial community composition and diversity in Haemaphysalis longicornis. Methods The metagenomic 16S rDNA V3-V4 profiling of bacteria were sequenced by Illumina Miseq PE300 sequencing platform to describe the bacterial community in H. longicornis ticks, to evaluate bacterial population diversity and to identify the predominant microorganisms and distribution of pathogens. Results A total of 1 070 624 Tags and 145 479 OTUs were obtained for the study. Rarefaction analysis showed a rare factional Shannon-Wiener index reaching a plateau, which indicated that sufficient numbers of sequences had been sequenced for diversity analyses and the richness of bacteria of H. longicornis. The predominated phyla in the H. longicornis were Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes sequentially. Gammaproteobacteria class showed the highest relative abundance. Also we identified a core bacterial community and divided the ticks into two groups. The 21 and 11 unique bacterial communities were detected in individual group, GⅠ and GⅡ respectively. A large number of pathogenic bacteria and opportunistic pathogens were found, there were no Spirochaeta and Mycoplasma present in the tick samples. Conclusion The bacterial community structure and distribution of pathogens obtained from H. longicornis ticks showed a high diversity.
Objective To grasp relationship between the tick species distribution and the distinctive landscape through a survey on ticks from different environments in Xinjiang. Methods Ticks were collected in 10 counties and cities throughout Xinjiang, including Hoxud county and Yuli county in southern Xinjiang and Bole, Habahe, Buerjin, Fuyun, Huocheng,Manas, Wusu and Urumqi in northern Xinjiang between April and June from 2011 to 2015. Free-living ticks were captured by drag-flag and men-bait trap, ticks parasiting in animals were collected from body surface of domestic animals. All ticks were identified morphologically. Results A total of 8 667 ticks belonging to 13 species of 5 genera, were collected from 14 sites of 10 counties in Xinjiang. Ixodes persulcatus and Rhipicephalus turanicus were the predominant species accounting for 20.08% and 19.75% respectively, followed by Dermacentor marginatus and D. silvarum accounting for 17.76% and 16.45% respectively. Hyalomma scupense, Haemaphysalis sculcata, H. punctate and Rhipicephalus rossicus were rare species accounting altogether for 0.40%. Ticks were distributed in Tianshan Mountain and Yili Tianshan valley region, Altai Mountain, Junggar Basin and Tarim Basin. The predominant species was Rh. turanicus (99.68%)in desert steppe of Tianshan Mountain, I. persulcatus (88.28%) was the predominant in coniferous and broad-leaved mixed forest, Ha. concinna(82.42%) in broad-leaved forest of Yili Tianshan valley. Dermacentor niveus (82.64%) in sub desert zone, D. marginatus(100%) in upland meadow, and D. silvarum (55.56%) and D. marginatus (44.44%) in upland steppe of Altai Mountain. Rhipicephalus turanicus (52.44%) and Hy. asiaticum asiaticum (44.07%) were the predominant species in arid land of Junggar Basin; Rhipicephalus (84.76%) in desert steppe and farmland in Tarim Basin, and Hy. asiaticum asiaticum was the only species found in diversifolia in Tarim River. Conclusion It was showed that different predominant species were found distinctively in 4 landscape regionalizations through studying the number of the tick species and the distributional environment type, and the species of tick and tick-borne diseases were determined by the landscape structure in Xinjiang.
Objective To establish a method to accurately identify the species of the female Sarcopha. Methods Thirty five mating pairs of eight Sarcopha species and 57 single male individuals of these 8 species were collected from October 25 in 2011 to October 27 in 2013. Their DNA barcodes were sequenced and 11 DNA barcodes sequences of these 8 species were also downloaded from the GenBank. Males were identified according to their genitalia, DNA barcodes differences between the intra-species, inter-sexes and inter-species were compared. Females were identified according to their mating males and the DNA barcodes, female's signum morphological characteristics of these eight species were illustrated and a key based on it was constructed. Results Inter-sexes DNA barcodes differences were 0-1.37% of these 8 species, and were comparable to the intra-species variations, and were lower than the 2% species limitation. The inter-species DNA barcodes differences were 4.56%-8.81%, there are distinct gaps between the intra-species and inter-species. The signum morphological characteristics were species-specific and could be used to identify the females. Conclusion DNA barcoding is a practical tool to identify the female Sarcopha. Species-specific morphological characters of the female could be developed based on the identification result of DNA barcoding, then provides references for the direct morphological identification of the females.
Objective To investigate the immunological characteristics and pathogenicity of China's first isolated mosquito borne viruses Nam Dinh virus (NDiV) on cultured cells and Kunming mouse. Methods The following methods were used:C6/36 cells for observation on cytopathic effect (CPE), plaque assay for determination of NDiV titer, virus inoculation methods for detection of NDiV virulence in 3 days old mice brain. In C6/36 cells, neutralization test was done using neutralizing antibodies from immunized Kunming mice. The BHK21 cells were inoculated with virus neutralizing antibodies of NDiV, one hour exposure followed by culturing for 7-9 d. Daily observation was made and the cytopathic effect was recorded. The TaqMan-MGB Probe Real-time PCR method was used to detect the nucleic acid of NDiV in C6/36 cells. Results C6/36 cells were infected after incubation with NDiV, CPE appeared since fifth days, the virus titer was 9.25×106 PFU/ml, the LD50 was 104.12/ml by Reed-Muench method. After NDiV virus infected mice, strong immunogenicity and higher rate of virus protection were showed in NDiV virus antiserum group, TCID50 was less than 10-1 while the control group TCID50 for 10-3.5. The neutralization index greater than 1 000. The virus nucleic acid detection results indicated positive 3 d after inoculation, virus nucleic acid showed significantly positive with growth of virus post inoculation upon virus nucleic acid increase. Conclusion The NDiV has certain pathogenicity and antigenicity against the exposed C6/36 cells and Kunming mouse.
Objective To understand the distribution characteristics of Hantavirus (HV) genotype in Hebei province, the HV strains isolated from rodents in 2012 and recovered from formerly saved were typed. Methods Lung samples were screened by immunoinfluscent assay (IFA). Antigen-positive lung samples were processed and inoculated onto cultures of confluent Vero-E6 cells. Formerly saved strains were recovered. Total RNA were extracted for genotype and identification. Results Four lung tissues were homogenized and inoculated onto confluent Vero-E6 cells. After the second-third passage, the characteristic HV antigen particle could be seen by IFA. At last, all four strains were isolated successfully. The formerly saved strains were used to infect fresh Vero-E6 cell cultures. After the first-second passage, the characteristic HV antigen particle can be seen by IFA. At last, all six strains were recovered successfully. All ten strains were typed by PCR and they belonged to SEO type. Conclusion SEO type was the predominant HV genotype in Hebei province. SEOV didn't produce cytopathic effects, but the virus can proliferate in the cell. HV can be saved for at least more than 20 years at -80 ℃. In China, Microtus fortis was an alternative host for SEOV.
Objective To analyze the expression levels of CpAPN in different instars of Culex pipiens pallens. Methods The APN cDNA sequence was identified and sequenced by quantitative Real-time PCR (qRT-PCR), and the relative expression levels of CpAPN were assessed in different instars of larvae using qRT-PCR assays. Results The full-length of CpAPN was 1 383 bp that encoded a protein of 460 amino acid residues. The homology with Cx. pipiens quinquefasciatus (XM001862270.1) was 100%. The qRT-PCR showed that APN was expressed at all stages of Cx. pipiens pallens, with the highest level in the 4th instar and the lowest level in the 3rd instar. There was no significant difference among the 1st, 2nd and 4th instars (F=2.465,P=0.250), but they were all higher than the 3rd instar significantly (F=49.191, P=0.000), which were 3.5 times, 3.7 times, and 4.0 times of the expression levels to the 3rd instar, respectively. Conclusion CpAPN showed significantly different expression levels in different instars of Cx. pipiens pallens. The results provided experimental evidences for revealing the function of CpAPN of the mosquitoes.
Objective To clarify age structure and fecundity of Rattus norvegicus population in Zhanjiang city, providing theoretical basis for early warning and formulating scientific prevention and control measures of rodent pests. Methods Rattus norvegicus were captured by cage traps from 2008 to 2011. Body weight, carcass weight, body length and tail length of test rats were measured. Reproductive organs were anatomized and developmental status was observed. Age groups were divided according to the frequency distribution characteristics of body weight and the developmental and reproductive status. Results Rattus norvegicus were divided into five age groups, juvenile group (Ⅰ,≤120 g), subadult group (Ⅱ,120-180 g), adult groupⅠ(Ⅲ, 180-240 g), adult group Ⅱ(Ⅳ, 240-390 g), and old group(Ⅴ, >390 g). Body weight and carcass weight between neighboring age class had extremely significant positive correlation. The overall fitting degree of age class based on body weight and carcass weight was high and the frequency dissimilarity rate was only 4.54%. The pregnant rate of the females kept increasing in all age classes and reached peak at age class Ⅳ. The average fetus and reproductive index kept increasing in all age classes. The size of testes kept increasing with age and the descending rate increased from 15.79% to 100%. Conclusion It was feasible to identify age classes by body weight. The population fecundity of R. norvegicus in Zhanjiang city kept growing in all age classes. The breeding population was mainly the adults and the old individuals.
Objective To evaluate the cytochrome C oxidase subunit Ⅰ(COⅠ) and cytochrome b (Cytb) gene as the DNA barcodes for identifying the rodent species in the Alataw pass, China-Kazakhatan. Methods The genome DNA were extracted from rodent samples of 7 species collected from Alataw pass, China-Kazakhatan during the 2013-2014. The mitochondrial COⅠand Cytb genes was amplified by PCR and sequenced. The phylogenetic trees were constructed by Mega 6.0 based on the nucleotide sequences of rodents published in the GenBank and the homology was analyzed. Results The 382 rodent samples of 7 species were clustered into 4 genera during the 2013-2014. The identification of COⅠ and Cytb gene results were 100% matched with the morphological analysis. Conclusion DNA barcoding can be used to effectively identify rodent species. DNA barcode technology provides a quick and accurate tool to identify the pathogen hosts and exotic medical vectors.
Objective To study species distribution, community composition and bloodsucking rate of hematophagous midges in 3 cities (countries) of China-Laos border. Methods Hematophagous midges were captured with light trap to generate data on the species distribution in China-Laos border in June to August, 2015. Results A total of 78 336 host-seeking midges belonging to 54 species and 3 genera were collected; genus Leptoconops with 4 species, genus Lasiohelea with 7 species, genus Culicoedes with 43 species. Seven species, C. gentiloides, C. huffi, C. kibabaluensis, C. lansangensis, C. parahumeralis, C. variatus, La. adita are recorded for the first time in Yunnan province. The species distribution of hematophagous midges was recorded 48 species in Mengla, 22 species in Jiangcheng, 16 species in Jinghong. The predominant species included C. jacobsoni, C. parahumeralis and C. palpifer, and their composition were 25.93%, 19.25%, and 17.13% respectively. The community composition and the bloodsucking rate of midges varied with different counties and habitats. The bloodsucking rate was 32.26% in residence district, and 28.24% in cowshed. Conclusion The investigation provides the reference for species distribution, community composition and studies of infectious disease by hematophagous Culicoides.
Objective The resistance level of nine local strains of Blattella germanica was divided into regions by clustering in Hebei province, providing the basis for regional control of B. germanica. Methods The method of contact with chemical cover was used in this study. The resistance ratios in different populations were categorized by clustering analysis. Results According to the theory of cluster analysis processing, the data of resistance levels were clustered to four categories to 4 groups. The first category is Shijiazhuang and Qinhuangdao strains: low to medium resistance to beta-cypermethrin low resistance to propoxur, high resistance to acephate and permethrin, medium to high resistance to deltamethrin; the second category was Baoding and Handan strains: low to medium resistance to beta-cypermethrin, acephate and deltamethrin, and low resistance to permethrin and propoxur; the third category was Zhangjiakou strain: high resistance to permethrin and acephate, medium resistance to beta-cypermethrin and deltamethrin, low resistance to propoxur; the fourth category was Cangzhou, Xingtai, Chengde, Tangshan strains: medium to high resistance to beta-cypermethrin, low to medium resistance to acephate, high resistance to permethrin: medium resistance to deltamethrin, and low resistance to propoxur. Conclusion Clustering analysis can be satisfactory tool to classify resistance levels in different regions.
Objective To study the genotype and epidemiological characteristics of Yersinia pestis in Hebei foci. Methods Primers were designed according to the confirmed 22 different segments (DFR), to genotype the 116 Y. pestis DNA of Hebei province. Results All of the strains lack these DFR of 01, 06, 07, 13, 15-18, to compare the genetic typing system of DFR, Y. pestis from Hebei province belong to the 17 genotype, distributed in the northern Kangbao county neighboring Huade, Baiqi, and Taipusiqi in the Inner Mongolia Autonomous Region. Conclusion The Y. pestis is stable genetically in Hebei plague foci, and have only one genotype, so the epidemic tends to stabilize.
Objective To study the infection of Schistosomiasis in small mammals and other final host after achieving control standards of schistosomiasis in Eryuan, explore small mammals' roles in schistosomiasis transmission in mountainous endemic regions in Yunnan province. Methods To capture the small mammals by night trapping method in the cultivated area with snail breeding around the villages. The infection by anatomical observation and stool examination after taxonomic identification of the small mammals. The infection of Schistosomiasis of residents and domestic animals, and situation on the snails were surveyed by the routine method,2010-2011. Results Six species, 4 genera, 3 families and 3 orders of 307 small mammals were captured in the schistosomiasis area. The rate of the captured was 12.79%. The predominant species were Rattus sladeni and Apodemus chevrieri, which accounted for 53.75% and 20.85% respectively. Among 305 small mammals being tested, one R. sladeni was infected with Schistosomiasis japonica, the infection rate of R. sladeni was 0.61%(1/165) and EPG(x) was 0.291, small mammals was 0.33%(1/305)and EPG(x) was 0.157. The infection rate of Schistosomiasis of humans, cattles, horses and dogs were about 1.01%(6/597), 0.83%(5/599), 0.58% (1/173), and 5.91% (13/220), and other animals were negative. The infectiosity EPG(x) of humans, cattles, horses and dogs were 0.009-0.010, 0.005, 0.007, and 0.080. There was statistical significance between the infection rate of Schistosomiasis of small mammals and dogs (χ2=15.339, P<0.05), as small mammals with others no significant differences. Density of living snails was decreased and no infected snail was found. Conclusion The result indicated the low infection of Schistosomiasis in small mammals in the area where it was achieved with control standard of Schistosomiasis. Further investigation may need to confirm the infection of Schistosomiasis in small mammals in some areas of mountainous valley region.
Objective To investigate the species and host of Paragonimus in Xinluo district of Longyan city. Methods The cercaria, metacercaria, and eggs of Paragonimus were inspected respectively in snails, crabs and wildcat feces, using clues from patients in October, 2015. Results As a tourist site, Wuxing village of Xinluo district was found as P. skrjabini epidemic area. Cerxaria was not found from 98 Semisulcospira libertine, 32 Bythinella and 5 Tricula jianouensis. Sinopotamon fujianense were infected by P. skrjabini metacercaria, as the second intermediate hosts. The infection rate was 31.43% (22/70). The number of metacercaria were 1.64 per positive crab and 0.21 gram of crab tissues, respectively. Conclusion The P. skrjabini infection rate was very high in S. fujianensis in Xinluo district. It may need further assessment on the control of S. fujianensis to prevent P. skrjabini infection in this area.
Objective In order to analyze the NADH dehydrogenase subunit 1 (ND1) gene of Echinococcus multilocularis from the wild rodents at Alataw pass, China-Kazakhstan. Methods The ND1 genes of E. multilocularis were amplified by PCR. The sequence was determined by Blast and phylogenetic analysis by Mega 6.0. The transmembrane domain (TM), signal peptide and B cell epitope of the ND1 genes of E. multilocularis were predicted and analyzed by DNAStar. Results The positive rate of E. multilocularis was 1.57%. The results showed that the ND1 genes of E. multilocularis had a length of 894 bp, encoding 297 amino acids. E. multilocularis were 100% closely related to the E. multilocularis AB018440 and AB720065. Conclusion The E. multilocularis can infect wild rodents at Alataw pass. The sequence information of E. multilocularis provides a basis for the scientific monitoring.
Objective To understand the daily activity rhythm of Aedes albopictus in Yongcheng city, and the results would be used for vector surveillance and control. Methods Double nets method used continually during daily time from 06:00-19:00, with capturing and counting for one hour interval separately. Results The biting activity of Ae. albopictus concentrated in the later afternoon (15:00-19:00). Conclusion Based on the ecological characteristics of Ae. albopictus in Yongcheng city, the surveillance time for Ae. albopictus should be carried during the later afternoon time (15:00-19:00), and the adult control with foging should also be implemented during the same time period (15:00-19:00).
Objective To observe the blood-feeding and oviposition behaviors of Culex pipiens pallens associated with the reproductive characteristics and to evaluate the vectorial capacity. Methods Observing the adult male and female ratio of different eclosion time, studying the relation between post-mating and blood-feeding of Cx. pipiens pallens and the influence of different oviposition substrate on the mosquito's egg laying behavior. Results The mosquitoes emerged on the first day were almost all males. There were two blood-feeding peaks for females post-eclosion. The blood feeding frequency of non-mated females was higher than the mated females. The feeding frequency of delayed mated females declined. The black color and the water that raised the larvae can attract the gravid females to oviposit. Conclusion The methods to interrupt mating are not suitable for controlling the Cx. pipiens pallens. The black color and the nutritious water could be used to the mosquito's traps.
Objective To establish a risk assessment index system for dengue fever in Wenzhou, assess risk of public health, providing evidence for the prevention and control dengue fever. Methods Dengue fever was assessed by 12 specialists; the results were analyzed through analytic hierarchy process in 2014. Results The risk assessment index system for public health of dengue fever was established in Wenzhou. The system included 1 target layer, 4 criterion layers and 19 index layers. Emergency handling ability of CDC (0.151), adult mosquito density (0.110) and Bretean index (0.110) were high risk factors. Dengue virus antibody of serum and the periods from onset to the first visit were relatively low. Meanwhile, the evaluation of the dengue fever in Wenzhou city was in high risk level by this indicator system. Conclusion There were risks of local outbreak of dengue fever caused by import cases in Wenzhou city, it is important to strengthen risk assessment for public health of emerging infectious diseases and import infectious diseases include dengue.
A newly recorded Fannia abrupta Malloch,1924 was collected from Baima snow mountain area in Deqin county, Yunnan province, China. This species belongs to Fanniidae, Fannia, serena-subgroup of the serena-group. So far the serena-subgroup has 39 species in Eurasia, and 24 species in China. This paper describes the morphological characteristics, proper citation origin of specimen, etc. The male genitalia were described for identification. Preliminary discussions were provided with regard to species number and the distribution of this group and subgroup.
To classify the tick specimens in Jiangxi province, the taxonomic principle and method of identified were used in this study. Through identification, the Ixodes ovatus and the I. granulatus were confirmed as two new records in Jiangxi. These records provide essential scientific information for their evolution in Jiangxi province.
A total 63 784 midegs were collected in the popular scenic spots, Jinggang Mountain and Lu Mountain in Jiangxi province during 2009 to 2014, two new species and 4 new records were found after classifying and identifying the specimens. Two new species were collected from Lu Mountain and Jinggang Mountain, which were named as Dasyhelea (Dasyhelea) lushanensis sp. nov. and Dasyhelea (Dasyhelea) wumazhaotiani sp. nov., respectively. Four new records were Dasyhelea (Dasyhelea)ampelis Yu, 2005; Dasyhelea (Dasyhelea) viduus Yu, 2002; Dasyhelea (Pseudoculicoides)dentiforceps Tokunaga, 1940 and Dasyhelea (Dasyhelea) paragrata Remm, 1972. Dasyhelea (Dasyhelea) lushanensis sp. nov. was resembled to Dasyhelea intosa Debenham, 1987, but the terminal of aedeagal parameral is not hook shape. Dasyhelea (Dasyhelea) wumazhaotiani sp. nov. was similar to Dasyhelea ampullariae Macfie,1934, but they can be distinguished by the morphology of the paramere with or without the curved twigs. The type specimens are deposited in the Medical Entomology Collection Gallery (Fengtai East street No. 20, Beijing 100071).
Objective Through malaria and typhoid fever outbreak investigation and control in foreign construction project site in Nigeria, experience and guidance were provided for the prevention and control of infectious diseases under the similar situations. Methods Procedures included field visits, retrospective investigation, etiology microscopy of Plasmodium falciparum, blood culture of typhoid fever cases in June, 2013. Results Among the 74 persons on the construction site, 3 was infected by malaria, and 4 by malaria and typhoid, 26 carrying Salmonella typhi, including the 3 chefs. Under the guidance of the advisory group, malaria cases were treated by standard protocols. Cases of typhoid fever and pathogen carriers were isolated and treated. Patients with malaria and typhoid fever as well as other health issues were dispatched back to China for further medical care. Conclusion Elimination of mosquitoes and breeding sources, strengthening personal protection, avoidance of mosquito bites were effective important measures to prevent malaria. It may need further study in Nigeria.
Objective Survey on ticks and host animals of severe fever with thrombocytopenia syndrome virus (SFTSV) in Huanggang, Hubei province, to provide basic data for the control and prevention of this vector-borne disease. Methods Ticks and animal serum samples were collected from affected areas from April to June in 2013, and SFTSV were detected by Real-time PCR. Results A total of 256 ticks were collected from grassland and livestock, after classification and identification, these collected ticks mostly were classified to 4 species, 4 genus, 1 family, Haemaphysalis longicornis was predominant species. The results of Real-time PCR of ticks, cattle and sheep serum samples showed that infection rates were 3.13%(8/256), 17.65% (3/17), and 12.50% (1/8), respectively. Conclusion Haemaphysalis longicornis was predominant species in Huanggang, the results of Real-time PCR indicated that the SFTS may transmitted by “host animals-to-ticks-to-human”, avoid tick biting is the key to prevent this disease.
Objective To investigate the susceptibility of Aedes albopictus larvae to four insecticides in some areas of Chongqing. Methods To determine the median lethal concentration (LC50) of the field population of Ae. albopictus larvae of Yuzhong district and Wanzhou district located in the hinterland of the Three Gorges Reservoir, by immersing them with pesticide in 2014-2015. Results In comparison with the susceptible strain, the resistance ratios of Ae. albopictus larvae to beta-cypermethrin, deltamethrin, permethrin, and temephos were 7.59-, 4.50-, 9.88-, and 3.18-fold respectively in Yuzhong district, and 12.82-, 7.50-, 13.29-, and 2.00-fold respectively in Wanzhou. Conclusion Aedes albopictus larvae of Yuzhong had a low level resistance to beta-cypermethrin, deltamethrin, permethrin, and temephos; that of Wanzhou had a moderate resistance to beta-cypermethrin and permethrin, but a low level resistance to deltamethrin. Therefore, it is important to rotate pesticides and choose appropriate doses in mosquito control.
Objective To investigate the current insecticide resistance status of dengue vector Aedes albopictus to commonly used insecticides in Mianyang city, so as to provide a basis for the rational use of insecticides. Methods The larvae dipping method was used to measure the insecticide resistance of the mosquitoes to commonly used insecticides. Results The resistance ratios of Ae. albopictus was 46.04-fold to deltamethrin, 45.18-fold to beta-cypermethrin, 249.60-fold to topermethrin for the highest, 2.44-fold to temephos, and 2.32-fold to DDVP for the lowest. Conclusion Aedes albopictus showed high resistance to pyrethroid insecticides, but low resistance to organophosphorus insecticides. Insecticides should be used strategically to hinder the development of insecticides resistance.
Objective To understand the species, density, seasonality, and the influence of observation sites of mosquitoes at Tianzhu free trade zone, and to provide scientific basis for mosquitoes control and mosquitoes-borne diseases prevention. Methods CO2 light traps were applied to collect adult mosquitoes from May to October, 2015, which were then identified and classified. Pathogens were also detected. Results A total of 4 749 adult mosquitoes that belonged to 3 genera, 5 species were trapped in 2015. Culex pipiens pallens were the predominant specie at Tianzhu (94.44%). Armigeres subalbatus, Aedes vexans, and Ae. dorsalis, whose density and number were usually very low, were captured for the first time at Tianzhu. Mosquito densities were high in June and September. The densities of mosquitoes at Tianzhu west and south were higher than that at Tianzhu north. The Japanese encephalitis and West Nile virus detection results were negative. Conclusion Culex pipiens pallens were the predominate specie in Tianzhu, which deserve more attention for control.
Objective To study the population distribution of mosquitoes and their seasonality in Jilin province and to provide reference for controlling mosquito-borne diseases. Methods From May to October in 2015, light traps were used for mosquito density surveillance in the urban areas of nine cities in Jilin province. Results A total of 13 397 mosquitoes (4 species, 3 genera) were collected, Culex pipiens pallens was the predominant species, accounting for 46.33% of all mosquitoes. The annual average density of mosquitoes was 1.00 mosquito per hour. The seasonality of mosquitoes was unimodal, and the peak occurred in August. Conclusion The population distribution of mosquitoes and their seasonality in the urban areas of Jilin province were well documented in this study. Culex pipiens pallens was the predominant species of mosquitoes in urban, the park, the hospital and rural residential areas. Besides, Aedes vexans was also predominant species in the barns. It is recommended to carry out mosquito control from June to September in Jilin province.
Studies on the mechanisms of insecticide resistance is very important to develop effective strategies for monitoring and managing insecticide resistance as well as new pesticide research. In the past several decades, a great deal of studies on insecticide resistance mechanisms, such as behavior, physiological function, metabolic action and target-site have been reported. It has been proven correct that mechanisms of insecticide resistance were confirmed by changed behavior, modified physiological function, enhanced detoxification and target-site insensitivity. Recently, with the development of the molecular biology, insect genomes and genetics, the molecular mechanism of insect resistance has been elucidated to much greater details. Some target genes have been identified and cloned in many mosquitoes. Some insecticide resistance related mutations have been screened out in some mosquitoes. This paper reviewed the progress in molecular mechanisms of mosquito resistance to insecticides. The alterations in genes related to insecticide resistance including amplification, over-expression and structure change were introduced in details．
With the decoding of the genetic material, taxonomy was developed rapidly based on genetic characteristics, various target genes continue to be discovered. It was summarized and reviewed that rodents related target gene of mitochondrial genome and nuclear genome were studied and applied, to provide reference for taxonomic identification and research.
This article summarized the experimental and practical experience relating to the vector control of the Xianning city in its progress of developing to national hygienic city, aiming to improve vector management. Furthermore, the summarized and generalized experience of the qualified work may provide a reference for other cities which are under the developing progress.
