Objective To investigate the seasonal variation of mosquito density and species diversity of mosquitoes in Tangshan, China, and to provide a scientific basis for effective mosquito prevention and control. Methods The mosquito surveillance data were obtained, using the light-trap method, from five surveillance sites in urban residential areas, parks, hospitals, suburban residential areas, and livestock sheds, in Tangshan, from May to October of each year during 2007-2018. The data were then used for measurement, comparison, and analysis of the density, species diversity, and seasonal variation of mosquitoes in different years/months and habitats. In this study, the Shannon-Wiener diversity index, Pielou uniformity index, Berger-Parker dominance index, and relative species abundance were used to study the diversity of mosquitoes. Results A total of 10 mosquito species were captured, i.e., Culex pipiens pallens, Cx. tritaeniorhynchus, Cx. modestus, Cx. vagans, Cx. fuscanus, Aedes albopictus, Ae. vexans, Ae. dorsalis, Anopheles sinensis, and An. yatsushiroensis. The mosquito density was 1.70 mosquitoes/light·hour, with the highest density observed for Cx. pipiens pallens (1.65 mosquitoes/light·hour). The composition of different mosquito species was different in different years ( χ ²=3 393.930, P<0.001). Among the different habitats, livestock sheds had the highest density of 2.94 mosquitoes/light·hour. According to the analysis of species diversity indices in different habitats, the diversity index and uniformity index of residential areas were the highest (0.23 and 0.14, respectively), and the dominance index of rural residential areas was the highest (0.98). The seasonal variation curve of mosquito density was unimodal, with a peak (3.75 mosquitoes/light·hour) observed in July. The species diversity index and uniformity index were the highest in August (0.31 and 0.17, respectively), and the dominance index was the highest in October (0.99). Conclusion Culex pipiens pallens is the dominant mosquito species in Tangshan. The highest mosquito density was observed in livestock sheds, and the mosquito species were most abundant in residential areas, with the most uniform density of different mosquito species. The highest dominance index was observed in rural houses. The highest mosquito density was observed in July, and the mosquito species was most abundant in August, with the most uniform density of different mosquito species, the highest dominance index was observed in October.

Objective To investigate the change in population density of mosquitoes and the resistance to commonly used insecticides against larvae and adults of Culex pipiens pallens in Tangshan city, and to provide a scientific basis for mosquito control for 2016 International Horticultural Exposition. Methods The mosquito lamp method was used to determine the population density of mosquito adults for International Horticultural Exposition park and surrounding area during 2013 to 2016. The larval immersion method and the adult exposure tube method were used to determine the resistance of Cx. pipiens pallens to commonly used insecticides. The DPS software was used to calculate the median lethal concentration and its 95%CI, virulence regression equation and Chi-square values. The resistance level of different insecticides was compared with Wilcoxon H test by SPSS 17.0 software. Results The average density of mosquitoes was 4.641 per lamp hour in Tangshan city from 2013 to 2016, with the predominant species Cx. pipiens pallens. The highest average density was found in the barn among all habitats (10.556 per lamp hour). Culex pipiens pallens were the predominant species in all surveillance areas. The population density of mosquitoes showed a single-peak throughout the year, peaking in July, being 10.854 per lamp hour. Larval Cx. pipiens pallens were susceptible to DDT, cypermethrin, temephos, chlorpyrifos, tetramethrin, bendiocarb and pyriproxyfen, with the resistance ratio of 0.88, 1.94, 0.82, 0.50, 2.18, 0.53, and 0.02, respectively. All of tested larval mosquitoes were intermediately resistant to bifenthrin with the resistance ratio of 14.00 and highly resistant to ethofenprox with the resistance ratio of 57.00. Culex pipiens pallens adults showed a mortality of 25.00% when contacted deltamethrin for 1 h and mortality of 50.00% when contacted permethrin for 3 h, all tested adults were resistant to deltamethrin and permethrin. Culex pipiens pallens adults experienced 100% mortality when contacted propoxur for 2 h, which was considered susceptible. Conclusion The predominent species were Cx. pipiens pallens, density peaked in July, when comprehensive control measures should be taken. More considerations are warranted about how to choose carbamate, organophosphorus and organochlorine insecticides, prevent or slow down the occurrence of the resistance.

Objective To explore the breeding status of mosquitoes in rain-water catch basin and sewer inspection pits of Shanghai district, and provide basic data for mosquito control in storm and sewer drainages. Methods Rain-water catch basin and sewer inspection pits of residential areas, parks and roads selected in downtown Shanghai, outskirts of town and suburb, were investigated to learn the mosquito larval breeding situation and the habits in July, 2017. Results Of the 878 basins, 41.69% of which had water, and the positive breeding-rate was 49.73%. The positive breeding-rate of flat grate type and vertical grate type were 50.36% and 47.67%. The average density of mosquitoes was 9.97 per dip. Of the 284 sewer inspection pits, 82.04% of which had water, and the positive breeding-rate was 18.88%, the average density of mosquitoes was 4.85 per dip, the positive breeding-rate of basins was significantly higher than in sewer inspection pits ( χ ²=57.643, P=0.000). The highest positive breeding-rate in flat grate type and vertical grate type was in residential areas, being 56.46% and 23.23%, the positive breeding-rate in parks were 45.35% and 12.50%; the positive breeding-rate in roads were 35.21% and 7.89%; the difference was statistically significant ( χ ²=10.433, 6.399, P=0.005, 0.042). There were Aedes albopictus (52.20%)and Culex pipiens pallens/quinquefasciatus (47.80%) breeding in basins. There were Cx. pipiens pallens/quinquefasciatus (70.45%)and Ae. albopictus (29.55%)breeding in sewer inspection pits. Conclusion The rain-water catch basins were important mosquito breeding ground in surface drainage system. The mosquito control of the rain-water catch basins should be strengthened.

Objective To assess and prevent the risks caused by vectors and the vector-borne disease during 2016 International Horticultural Exposition. Methods Judging the hazard caused by vectors and the risk classification of vector-borne diseases by risk assessment index matrix method and Borda sequence value method. Results It was high risk for the vector biting and infestation and food poisoning caused by vectors, it was middle risk for the cable damage and communication and power facility disruption. The prevalence of Japanese encephalitis (JE), malaria, plague, and hemorrhagic fever with renal syndrome (HFRS) were at high risk. The prevalence of dengue fever, yellow fever, filariasis, Zika virus disease, leptospirosis, murine typhus, and tsutsugamushi disease were at middle risk. Food poisoning caused by vectors ranked the first in vector harm by Borda sequence value method, vector biting and infestation and communication and power facility disruption by vectors ranked the second. JE, malaria, and HFRS ranked the first in vector-borne diseases. Dengue fever, yellow fever, filariasis, Zika virus disease, leptospirosis, murine typhus, and tsutsugamushi disease ranked the forth. Plague ranked the eleventh. Conclusion The integrated application of risk matrix and Borda count is effective in assessing the risk levels of the hazards caused by vectors and the vector-borne disease, and therefore is worthy of wide promotion.

Objective To explore the status of Culex pipiens molestus infestation in different types of underground garages of Shanghai downtown during winter and spring. Methods Larval sampling was conducted in 4 selected underground garages in Shanghai Huangpu district during December to June. Collected larvae were laboratory-reared until adult emergence, and then identification was attempted by male genitalia morphology. Results Of the 4 underground garages, the crude species composition of Cx. pipiens molestus reached 90.48%, especially in winter and early spring which reached 100% in some garages; as the season changes, this proportion of Cx. pipiens molestus decreased significantly (100% to 67.11%). The proportion of Cx. pipiens molestus in Garage D was significantly higher than the other 3 ones (χ²=24.579, 17.053, and 16.025; P < 0.01). The genitalia DV/D ratio of Cx. pipiens molestus from 4 garages varied significantly (χ²=-0.002, -0.021, 0.004, -0.027; F=19.586, P < 0.05); the maximum value ranged from 0.054 to 0.192. Conclusion Featured with high density of underground garage and high prevalence of underground Cx. pipiens molestus infestation, mosquito control still have a long way to go in downtown Shanghai.

Objective To explore the status of mosquito infestation in different types of underground garages in downtown Shanghai, and to analyze the causes and suitable countermeasures. Methods Randomly selecting 101 underground garages in Shanghai Huangpu district, conducting mosquito breeding status investigation during July and August, 2014. Results Of the 101 underground garages, the crude and adjusted positive breeding-rate was 35.64% and 39.13%, respectively, and the positive breeding-sites rate was 21.36%. Compared with the commercial building garages, the positive rate of underground collecting-wells(UCWs)in residential garage was significantly higher, and the positive rate of UCWs in bicycle garages are significantly higher than those in car garages. Comparison of different types of garages shows that the mosquito infestation in large-scale garages and multilayer ones are much higher (77.78% vs. 28.13%, χ²=11.434, P=0.001; 29.63% vs. 12.86%, χ²=6.740, P=0.009). Conclusion Featured with high density of underground garages and high degree of underground mosquito infestation, mosquito control still have a long way to go in downtown Shanghai. Compared to chemical mosquito-control measures, physical ones are recommended.

Objective To investigate the seasonal variation and geographical distribution of different fly species in downtown Shanghai. Methods Conducted fly surveillance during March to November of 2013 in 2 parks and 1 residential area in Huangpu district, and then did identification and classification. Results The fly density in park environment was significantly higher than residential environment (Z=-2.870, P=0.002). Although shared the same dominant family of Calliphoridae, the flies species compositions were different between the 2 kinds of environments, Chrysomya megacephala was the predominant fly species in parks (composition ratio is 23.43%) and Lucilia sericata was the predominant one in residential (composition ratio is 20.11%). Different fly species showed different seasonal peaks and distribution trends, C. megacephala and Lucilia (s. str.) illustris had the unimodal trend,while L. sericata, Aldrichina grahami and Fannia prisca showed the bimodal trend. Conclusion The study suggests the work of fly prevention and control in downtown Shanghai should focus on the predominant Calliphoridae, such as genera of Lucilia and Chrysomya.

Objective To explore the status of mosquito infestation in different types of residential areas in downtown Shanghai, and to analyze the causes and countermeasures. Methods Selecting 3 mosquito monitoring sites from 3 different types of downtown neighborhoods in the same area, conduct 224 days’ continuous mosquito monitoring in CO₂-light trapping method. Results Aedes albopictus is the predominant mosquito population in residential areas of downtown Shanghai (account for 72.35%), significantly higher than the density of sub-dominant Culex pipien pallens population (11.91 vs. 4.21/day·machine, P<0.05); Compared with the type of high-rise residential and old-fashioned villas environments, the old neighborhood environment faced more serious mosquito-infestation conditions, which has significantly higher mosquito density (total mosquito density, 28.91/day·machine, P<0.05), and much higher Ae. albopictus proportion (76.60%, P<0.05). Conclusion The situation of Ae. albopictus infestation in residential areas of downtown Shanghai is quite concerned, especially in old neighborhoods, whose living conditions and sanitary facilities are relatively poor. It is recommended that countermeasures should be taken to cope with the threat of Ae. albopictus-borne infectious disease in residential areas.

Objective To learn the vector infestation status in five-star Hotels of Huangpu district before the CICA- Summit, and to provide scientific justification for vector prevention and control. Methods Randomly selecting 10 five-star hotels responsible for CICA-summit reception,the vector infestation status in these hotels were investigated in visual method and evaluated according to the Shanghai Local Standards. Results The failure rate of rodent control in 10 hotels was 40% and 10% (4 and 1) respectively in the two rounds of survey. There was significant improvement after the first round feedback, the positive rate decreased significantly (1.24% vs. 0.38%, P=0.048) and the pass rate of rodents was improved significantly (97.19% vs. 99.10%, P=0.006). The cockroach control failure rate was 40.00% and 50.00%, respectively, the positive rate also decreased significantly after the first round feedback (1.87% vs. 0.74%, χ²=3.942, P= 0.047). The positive mosquito breeding sites was found in individual underground garage wells. No obvious fly and bedbug infestations were found in the two rounds of survey. Conclusion Five-star hotels vector infestation were found mainly in the kitchen, food storage and processing rooms, laundry rooms and other non-public areas, mice and cockroaches were the predominant vector for infestation, which may be attributed to the hotels'complex environment and management deficiencies. Appropriate pest proof measures, specific supervision, modifications and improvement in the star hotel standards were advisable.

This study reports one new record of the genus Fannia in Shanghai, China: Fannia dupla Nishida, 1974. This new fly species was cage-trapped in the green belt of Huaihai park of Shanghai and was considered migrating from the outside of Shanghai area. The F. dupla was recorded only in Japan and Taiwan province of China before, but in recent years, it was reported also in Beijing and Fujian province, besides, we found this fly species in 2 consecutive years in the same area of Shanghai (2012 and 2013). The present paper deals with the diagnostics, and the possible biology, distribution of this particular species．

Objective To explore the mosquito population dynamics in different seasons and mosquito circadian rhythm in different periods of a day. Methods Conduct more than 224-days'continuous monitoring of adult mosquitoes by CO₂ trapping method to get the adult mosquito data in five different monitoring-sites in Shanghai People's Square and People's Park region. Results The monthly-distribution of mosquito species was significantly different in downtown Shanghai. As the most dominant mosquito species, Culex pipiens pallens reached an average density of 13.35 pcs/(day·site), and peaked in May and June (19.93 and 28.19 pcs/day·site, respectively); Aedes albopictus and Cx. tritaeniorhynchus both peaked in July (10.77 and 8.79 pcs/day·site, respectively). The circadian rhythm analysis showed that the largest proportion of mosquito appeared in the evening and early morning hours (20:00-08:00a.m.), followed by the nightfall hours (16:30-20:00), and Cx. pipiens pallens was the dominant species in the 2 period (78.14 and 66.05%, respectively); the daytime hours (08:00a.m.-16:30) had the least proportion, whose dominant species was Ae. albopictus (65.70%). Conclusion The monthly-distribution and circadian rhythm were different in mosquito population species and density, which can be attribute to the ecological difference of different mosquito species, but except that, we surmise the special urban environment and urban light pollution should also account for, and which should be confirmed by further study.

Objective To investigate the population dynamics, temporal distribution, and stinging indices of mosquito population in the downtown Shanghai, China. Methods Five mosquito?lmonitoring sites were set up in Shanghai Peoples Square and Peoples Park areas, where mosquitoes were frequently encountered. A 194-day continuous dynamic monitoring of adult mosquitoes was conducted by human landing catch. Results During the 194-day surveillance from late April to late October, 2012, a total of 1666 adult mosquitoes of 5 species and 3 genera were collected. The proportions of Aedes albopictus and Culex pipiens pallens were 71.1% and 27.7%, respectively. The high daily fluctuation of adult mosquitoes was observed. Most of the mosquitoes were captured during July to September, with a peak of 52 mosquitoes per day. Cx. pipiens pallens peaked in early June, and its population density was significantly higher than that of Ae. albopictus in May and June (P＜0.05). Ae. albopictus peaked in late July, and its population density was significantly higher than that of Cx. pipiens pallens during July to September (P＜0.05), so it was the predominant species during that period. Conclusion This is the first report on mosquito infestations in downtown area as the results of 194-day continuous surveillance based on human landing catch. The results suggested that routine mosquito monitoring methods have limitations and inaccuracy. Targeted and efficient measures with special focus on the two predominant mosquito species, Ae. albopictus and Cx. pipiens pallens, should be introduced into the prevention and control of mosquitoes in downtown Shanghai. Furthermore, the study suggested that the increasing suitable sites for overwintering mosquitoes are more likely to cause an earlier arrival of Cx. pipiens pallens peak in the studied areas.

Objective To study the mosquito population dynamics in different microenvironments of the same region and to analyze the relevant factors contributing to the differences in mosquito population dynamics in downtown Shanghai. Methods Five mosquito?monitoring sites were set according to the geographical distribution in the park and grassy areas of downtown Shanghai (People’s Square and People’s Park) where mosquitoes were frequently encountered. Adult mosquitoes were continuously monitored by CO2 trapping method for more than 220 days to determine the differences in mosquito population dynamics at the five monitoring sites. Results The 224 days continuous adult mosquito monitoring showed that the number and density of adult mosquitoes at the 5th monitoring site were 9737 mosquitoes and 43.50 mosquitoes/day·machine, significantly higher than those at the other four monitoring sites (P＜0.01), and the adult mosquito density in the People’s Square was significantly higher than that in the People’s Park (29.80 vs. 11.13 mosquitoes/day·machine; t＝-5.552, P＜0.01); as to the adult mosquito population, the constituent ratio of Aedes albopictus in the People’s Square was significantly higher than that in the People’s Park (25.32% vs. 9.54%; χ2＝187.923, P＜0.01), and the constituent ratio of Culex tritaeniorhynchus in the People’s Park was significantly higher than that in the People’s Square (18.46% vs. 2.77%; χ2＝187.923, P＜0.01); Cx. tritaeniorhynchus was the dominant species in the 2nd monitoring site (constituent ratio 48.55%). Conclusion The mosquito density and population vary significantly in different microenvironments of the same region, which may be attributable to such factors as breeding environment and human disturbance. The surveillance and control of Cx. tritaeniorhynchus should be implemented in downtown Shanghai.

Objective To investigate the mosquito infestations in different schools in the central urban area of Shanghai, China and to assess the risk of mosquito-borne diseases among the students. Methods Five nurseries,4 primary schools, and 3 secondary schools in Huangpu district of Shanghai were randomly selected for investigation. The mosquito infestations in the nurseries and schools in June and August 2012 were evaluated by investigation of mosquito breeding sites and human-baited trapping. Results The mean densities of Aedes albopictus in nurseries, primary schools, and secondary schools were significantly higher in August than in June (0.25 vs. 0 mosquito/30 min·monitoring point; 3.67 vs. 0.92 mosquitoes/30 min·monitoring point; 0.11 vs. 0.06 mosquito/30 min·monitoring point, with over 100% increases when comparing the former with the latter in each pair). In August, the densities of adult mosquitoes in nurseries and primary schools were 0.45 and 3.67 mosquitoes/30 min· monitoring point, respectively; there were also increases in the positive rates of small ponded waters as breeding sites in nurseries and primary and secondary schools (47.1% vs. 16.7%; 34.5% vs. 28.6%), and the positive rate increased significantly in nurseries (χ²=3.970, P=0.046). Conclusion The indices of mosquito infestation and numbers of mosquito breeding sites per school in the central urban area of Shanghai are significantly higher than the local standards, and they show significant increases in summer. It is recommended that the education sector and schools should enhance environmental management in campus and ensure the health of teachers and students.

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.

【Abstract】 Objective To explore control efficacy of one?dose Japanese encephalitis（JE） attenuated live vaccine in 1-3 years in JE endemic areas, and provide the evidence for its control. Methods The children who only inoculated one?dose JE attenuated live vaccine from 2004 to 2006 in Guizhou were investigated, and its incidence rate within 1-3 years after inoculation was analyzed. At the same time, the immunization retrospective study to all the JE confirmed cases was done. Results The incidence rate of JE immunization county declined 62.36% compared to that of last year, but  it  rebounded  after  inoculation  for 1-2 years in some counties. Among the cases investigated, the targeted children accounted for 73.28％. No JE vaccine had been inoculated in 27 cases sampled randomly. The incidence rates of objectors were no significant difference after immunization for 1-3 years(χ2＝0.73, P＞0.05), which were 6.25/100 000, 5.77/100 000 and 4.54/100 000, respectively. The inoculation rates were 1.92% among 52 diagnosed cases, lower than that of the control(29.41%), and significant difference was found between them (χ2＝52.74, P＜0.01). Conclusion The long?term control efficacy of one dose JE attenuated live vaccine is very good after inoculation for 1-3 years , and the effective method to realize control efficacy is the increase of inoculation rate. The rebound of incidence rate was related to the actual inoculation rate in some counties after immunization for 1-2 years.

【Abstract】 Objective To compare the developmental duration and vector capacity of malaria transmission of Anopheles anthropophagus from Liaoning and Jiangsu on pre-mature stage. Methods In laboratory, An.anthropophagus from Liaoning and Jiangsu were reared in the same environment and infected artificially in vitro. The biological indexes such as hatchability, emergence rate, pupation rate, the positive rate of mosquito stomach and oocyst and sporozoite infection rate of salivary gland were observed, respectively. Results   The average developmental duration of egg from Liaoning population and Jiangsu population were 3.66 d and 3.84 d, and the hatchibility of egg were 76.0% and 74.3%. That of larva were 6.67 d and 8.26 d and the pupation rates were 94.7% and 96.0%. That of pupa were 1.60 d and 1.72 d and the emergence rates were 97.2% and 98.6%. The positive rates of mosquito stomach and oocyst were 25.1% and 28.1%, and the sporozoite infection rates of mosquito salivary gland were 8.4% and 10.7%. Conclusion It was no significant difference statistically between the developmental duration of larva and vector capability of malaria transmission of An.anthropophagus from Liaoning and Jiangsu （P＞0.05）. Therefore, the surveillance of vector should be strengthened during malaria transmission period.

【Abstract】 Objective To develop a molecular technology to assay human blood index of Anopheline mosquito which could substitute for the traditional immunological method. Methods A pair of specific primer were designed according to the sequence of human rDNA, and the human blood in Anopheline mosquito was identified by polymerase chain reaction （PCR）. Meanwhile, the DNA extracted from the blood of pig, cattle, goat, mouse and the mosquito without bloodsucking were detected to verify the specificity  of  the  method.  And the DNA extracted from the mosquitoes after its bloodsucking for different time （such as 1 h, 6 h, 12 h, 18 h, 24 h, 27 h, 30 h, 33 h, 36 h, 40 h, 44 h, 48 h） were detected to determine the sensitivity of the method. Results The specific PCR product （519 bp） was amplified from the DNA extracted from human blood.  No specific PCR product was found either from the blood of other animals or from the mosquitoes without bloodsucking. The specific bands were produced from all the mosquitoes within bloodsucking for 24 h. After bloodsucking for 27 h, 30 h, 33 h and 36 h, only 4, 4, 2, 1 mosquito could produce specific bands in the total of 5 tested mosquitoes, respectively. No specific PCR product was amplified after feeding for 40 h. Logistic regression analysis indicated there was a negative correlation between the bloodsucking time and the quantity of positive mosquitoes detected by PCR after bloodsucking for 24-40 h （P＜0.01）. Conclusion The PCR method developed in this study could identify human blood in Anopheles sinensis within bloodsucking for 24 h accurately， which could replace the traditional immunological method.