Objective To investigate the species compositions of rodents and the chigger mites on their body surface and the infection rate of Orientia tsutsugamushi in rodents in Yongcheng, Henan province, China, and to provide a scientific basis for the prevention and control of scrub typhus in Yongcheng. Methods Rat traps were used to capture rodents and to collect ectoparasites from the body surface of rodents in different survey sites and different habitats in Yongcheng in October 2017. Nested PCR was used to detect nucleic acid of O. tsutsugamushi. The rodent density, chigger infestation rate, chigger index, and pathogen infection rate were calculated. Results A total of 110 rodents were captured with a capture rate of 12.21%. Apodemus agrarius accounted for 90.00%. A total of 1 249 chigger mites were collected from rodents. The chigger infestation rate and chigger index were relatively high in the forest along the riverbank, wetland, and mountain forest. Leptotrombidium scutellare (96.86%) was the dominant chigger mite species, which was mainly parasitic on the body surface of A. agrarius. The O. tsutsugamushi positive rate of rodent was 10.48%. Apodemus agrarius, Rattus norvegicus, and Mus musculus were detected O. tsutsugamushi positive with nPCR. Orientia tsutsugamushi in Yongcheng belonged to Kawasaki molecular type. Conclusion This study confirms that there are some epidemic foci of scrub typhus with host rodents in Yongcheng, which have the same hosts and vectors as the surrounding epidemic foci of scrub typhus.

Objective To compare the effectiveness of 4 adult mosquito sampling methods. Methods All the experiments were carried out in sheepfolds during mosquito active season around-the-clock continuously for 2 circles rotating positions one by one in Yongcheng city, Henan province. The mosquitoes were collected and sorted separately in the daytime (09:00-18:00) and nighttime (18:00-09:00 the next day). Results The results in the daytime did not give us any specific indication except all the tools did not work well as surveillance tools during daytime. All the monitoring tools caught the main mosquito species in the residential areas at nighttime, but all of them had the unexpected other insects especially the most in Kung Fu Xiao Shuai. Kung Fu Xiao Shuai showed excellent results in trapping Culex tritaeniorhynchus and Anopheles sinensis; BGS-trap and WJ-C captured a small number of mosquitoes; Maisicui caught a variety of mosquito species with the appreciable density for surveillance work. Conclusion Kung Fu Xiao Shuai might be a good surveillance tool for Cx. tritaeniorhynchus and An. sinensis; Maisicui could work as a good mosquito surveillance tool in general; this study can be used to evaluate the mosquito monitoring tools partially and the selection and replacement of monitoring tools need further efficacy evaluation.

Objective To decide the predominant mosquito species in Yongcheng city, and their natural occurrence, density, seasonal fluctuation, and habitat distribution. The results will guide the vector management in this area. Methods Light-trapped method was used twice a month in three towns which lies in different direction in Yongcheng area. Dwellings, houses premises, and livestocks were selected as the surveillance sites in each town. Excel 2007 and SPSS 20.0 were used for data analysis. Results The total mosquito number obtained in 2010 were 20 684 with the average density 34.08/(trap·night). Culex tritaeniorhynchus took up to 54.12%, which was the predominent species. The mosquito density in livestocks was 50.58/(trap·night) which was the highest; the mosquito density around dwellings and their premises had no significant difference. Mosquito density showed statistical significance in 3 surveillance habitats (F=74.450, P<0.01). Mosquito density began to increase in July, reach a small peak activity in late July, and reached the highest peak activity in September, followed a decline in October. The mosquito density in Renhu and Mengzhuang villages reached the peak in early September, showed a unimodal peak activity. Renhu had the highest mosquito density. Three towns showed statistically significant differences in mosquito species and their density (χ²=2 033.097, P<0.01). Conclusion The distribution of mosquitoes in Yongcheng city varied according to habitat and village characteristics, then the mosquito prevention and control work should be based on the mosquito distribution in different habit, different village, and seasonal performance by species in this area.

Objective To investigate rodents, chigger mites and Orientia tsutsugamushi on mountains and plain in Qing' an county. Methods Small mammals were trapped by snap traps in September, 2013. Rodents and their ectoparasites were collected and identified morphologically. Then the rodents were dissected under sterile conditions. DNA was extracted from the spleens, nested-PCR was performed to amplify and sequence the 56 kD type-specific antigen gene of O. tsutsugamushi from all samples collected in this area. Results A total of 107 small vertebrates including 9 species were captured. Apodemus agrarius was the predominant species in outdoor rural settlements and farmland. While Rattus norvegicus and Mus musculus were the predominant in indoor environment. Apodemus agrarius and Ap. peninsulae were the predominant species in forest areas. A total of 1 164 chigger mites were collected from small mammals, including Neotrombicula gardellai, Leptotrombidium orientalis, N. japonica, and L. subintermedium. Chigger mite index on M. rufocanus was highest (65.50), then T. triton (58.13), C. rutilus (22.86) and Eutamias sibiricus (24.00). No chigger mites were found in rural settlements and farmland far from forest. Orientia tsutsugamushi was detected from T. triton and Ap. peninsulae by nested-PCR. Conclusion The composition of the small mammals and chigger mites species is similar to those in the north of Northeast China. Orientia tsutsugamushi was firstly detected in rodents in the county. Therefore Qing' an is an new natural focus of scrub typhus and human infection should be investigated in the future.

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 investigate the rodents species diversity along the border area of China and Kazakhstan, and provide supporting data for the surveillance and control of rodent borne diseases. Methods Rodents were collected with trapping method at seven counties/districts and area in Yili, Boertala, Tacheng and Karamay. Rodents species were then identified with DNA barcodes. Results Totally 174 samples of small mammal were collected from three kinds of habitats, including 16 species of rodents belonging to Muridae, Cricetidae, Dipodidae, Gliridae and Sciuridae, and one shrew species of Soricidae. With the DNA barcoding method, samples belonging to two vole species(Microtus arvalis and M. gregalis) with similar morphologic characters were identified correctly. Gerbil samples recognized morphologically as Meriones meridianus were different genetically from M. meridianus from Eastern China. Conclusion High diversity of rodent species were found in alpine forests meadows and desert steppe habitats. The genetic distances between M. meridianus from northern Xinjiang and other areas of China are so profound that suggests there are cryptic species.

Objective To understand the distribution of rodents, dynamics of rodent density and composition in hydro-fluctuation area of Three Gorges Reservoir after experimental storage, and provide evidence for the risk prediction and control of rodent-borne diseases. Methods Four surveillance sites were set in upper, middle and down reaches of the Three Gorges Reservoir and surveillance were carried out twice after water drainage and before water storage every year. The small mammal density and the species composition in different regions, altitude and periods were analyzed. Results During 2010-2014, a total of 116 small mammals were captured and the average capture rate was 1.10% and on the decline overall. The captured small mammals were classified into six species. Apodemus agrarius was the predominant species accounting for 46.55% and Anourosorex squamipes was next with 25.86%. The average capture rate after water drainage (1.23%) was higher than that before water storage (0.90%). All captured small mammals distributed in all three altitude and the composition decreased from high to low latitude. The predominant species was different in three altitude. The predominant species in 166-175 m altitude was A. squamipes accounting for 44.45%, followed by Rattus tanezumi (18.52% ); In 145-155 m and 156-165 m altitude, Ap. agrarius was predominant species accounting for 84.00% and 72.97%, respectively. Conclusion The average capture rate was low and there was various species of rodent in hydro-fluctuation area. The density and species composition of small mammals varies with different regions, altitude and monitoring time. The host animals of hemorrhagic fever of renal syndrome, Leptospinosis and commensal rodent plague may be of risks in hydro-fluctuation area of Three Gorges Reservoir. It should be strengthened to monitor the host animals and take the corresponding control measures in the area based on the risk assessment.

Objective To detect the infection with Bartonella henselae in Haemaphysalis longicornis. Methods Haemaphysalis longicornis captured in Lingshou county, Shijiazhuang, Hebei province, China, were divided into groups. The H. longicornis in each group was disinfected, sterilized, and grinded. Half of the grinded mixture was directly used for DNA extraction and polymerase chain reaction (PCR) analysis;the other half was inoculated onto tryptic soy agar supplemented with 5% defibrinated sheep blood followed by culturing in a 5% CO₂ incubator at 37 ℃, and the suspected colonies were selected for PCR analysis. The PCR products that produced positive bands were sequenced, and the nucleotide sequences obtained were aligned with known sequences in GenBank. Results A positive band was observed in one sample from direct DNA extraction, the sequence of which was found to belong to B. henselae by alignment analysis. Positive bands were observed in two DNA samples isolated from bacterial cultures, but no results were produced from sequencing. Conclusion Haemaphysalis longicornis collected in Lingshou county, Shijiazhuang, are infected with B. henselae. This is the first detection of B. henselae infection in H. longicornis.

Objective To evaluate the efficacy of ultra?low?volume (ULV) spraying and residual spraying, and the combined application of the two, in control of mosquitoes. Methods We used ULV spraying and residual spraying, alone or combined, to control mosquitoes. Mosquito density was monitored using animal?baited net traps, light traps, and labor hour method before and after application of the controlling methods. Results Residual spraying reduced indoor mosquito density, but had no significant effect on outdoor mosquito density. ULV spraying reduced indoor mosquito density too. However, mosquito density monitoring using light traps showed increased density after ULV spraying, while monitoring using animal?baited net traps showed decreased density. Conclusion Combined use of residual spraying and ULV spraying can improve mosquito control efficacy. Mosquito density monitoring using goat?baited net trap is a reliable method in evaluating the mosquito control effect of ULV spraying.

Objective To compare the mosquito-trapping effects of lamp trapping method and labor hour method, and to provide a reference for scientific and standard investigation and surveillance of mosquitoes. Methods Three sites were selected for study based on their different distances from the Three Gorge Dam in the Three Gorge Reservoir area. The mosquito species composition was investigated by lamp trapping method and labor hour method in the residential area and its surrounding area at each of the three sites. Results Both lamp trapping method and labor hour method could be used for successfully trapping the main species of mosquitoes in the Three Gorge Reservoir area, but with difference in the species composition of captured mosquitoes. More Culex tritaeniorhynchus was captured with lamp trapping method than with labor hour method, while much more Armigeres subalbatus was captured with labor hour method than with lamp trapping method. The application scope of lamp trapping method was wider than that of labor hour method. The lamp trapping method could be applied in the places without space limitation, such as forest and rice field. Conclusion Each mosquito trapping method has its own advantages and disadvantages. Lamp trapping method is recommended in the long-time investigation and surveillance of mosquitoes.

Objective To evaluate the efficacy of 11 kinds of cockroach baits. Methods Ten adults of Blattella germanica (half male and half female) with feed, water and cockroach baits were put into a beaker. Three replications were made for each bait with blank control. Twenty-four hours later, the cockroach baits were taken out and the LT ₅₀, water loss rate and feeding amount were calculated. Results All of the eleven kinds of cockroach baits can kill B. germanica within 96 hours, meeting grade A of national standards (GB/T 13917.7-2009), but their LT ₅₀, water loss rate and feeding amount are quite different. Conclusion Eleven kinds of cockroach baits can effectively kill B. germanica. Comprehensive evaluation based on the needs and site conditions should be done to select the most suitable cockroach bait.

Objective To understand the breeding condition of dogs and cats and their cat flea, Ctenocephalides felis, infection in several areas of China, so as to provide basic evidence for cat flea and related infectious diseases prevention and control. Methods Door-to-door household survey was used to know the dogs and cats feeding condition in the suburb of Beijing, and rural areas of Qingdao of Shandong province and Dali of Yunnan province. C. felie abundance in stray cats, domestic dogs and cats were evaluated using body surface examination, free flea collection on the ground, flea eggs investigation as well as retrospective survey methods; and the seasonal fluctuation of C. felis in suburb of Beijing was studied using the flea eggs investigated method. Results (1) In Beijing suburb, 64.52%-83.87% of peasant households kept dogs with an average of 0.84-1.87 dogs per household, 69.2%-86.8% of the dogs were not chained, and 2.94%-6.45% of peasant households had free- roaming cats. In rural areas of Pingdu Qingdao of Shandong province 40.43% of households kept dogs, with an average of 0.50dog per household and more than 36.5% of those dogs were not chained. (2) The infection rate of C. felis in cat in rural areas of Qingdao and Beijing was 100%, while only 3.85%-19.15% of dogs were infected with Pulex irritans and C. felis. (3) In winter, C. felis still could lay a large amount of eggs in Beijing. Conclusion There were a great number of domestic dogs but few domestic cats in the rural and urban-rural areas of China, most cats were homeless. C. felis can develop on the surface of cat throughout the year. It is very important to enhance the management of stray cats and to pay more attention to the prevention and control of C. felis and other infectious diseases.

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 study the flight range of Anopheles sinensis and provide evidence for the development of control measures for malaria elimination in China. Methods The mark-release-recapture technique was used to preliminarily study the flight range of An. sinensis. The 3000 wild An. sinensis were captured and marked with green fluorescent powder and released at the specific site of Yongcheng city. Subjects were recaptured for ten successive days using light traps and fluorescent detection. Results Twenty-five of the 3000 released An. sinensis were recaptured, resulting in a recapture rate of 0.83%. The number of recaptured An. sinensis varied over time; one on day 0 (the day of release), fourteen on day 1, eight on day 2, one on day 3, and one on day 6. No marked An. sinensis were recaptured on the other days. The number of recaptured An. sinensis also varied by location; the number of recaptured An. sinensis was significantly higher to the east and south of the village than to the west and north. Eighty percent of the marked An. sinensis were recaptured within 100 m of the initial release site with a maximum flight distance of 400 m. Conclusion This is the first study of An. sinensis flight-range patterns using the mark-release-recapture technique in China. In this study, the recapture rate was low, and most marked An. sinensis were recaptured within a 100 m radius of the release site with a maximum flight distance was 400 m. Given preliminary data on An. sinensis flight patterns, the management area of disease control efforts in future malaria epidemics should cover a radius up to 500 m from an epidemic focal point, with most resources concentrated within a 100 m radius.

【Abstract】 Objective The species of rodents was investigated along the Qinghai-Tibet Railway in representative areas where Norway rats (Rattus norvegicus) might be distributed in Tibetan Autonomous Region. Methods Rodents were trapped by snap trap, live trap and glue boards in different habitats in Lhasa, Nagqu and Nyingchi. The rodents captured were identified, then the densities and population constitutes of them were calculated. Results A total of 126 rodents were captured with 1817 snap traps. R.norvegicus did not be captured in the areas investigated. R.tanezumi was the dominant specie in Lhasa and Nyingchi, accounting for 84.1% and 70.0% respectively, while Mus musculus in Nagqu accounted for 98.1%. Conclusion The dominant species of rodents are R.tanezumi and M.musculus in the residential areas investigated, and no R.norvegicus was found.

【Abstract】 Objective To deeply know the role of the reporting of dead rodents in the monitering and control of commensal rodent plague and its cooperation with linking surveillance method. Methods  （1）To compare and analyze the function of dead rodents reporting and three plague?risk indicators reporting on the timely finding of the plague in rodents. （2）To analyze the relationship between dead rodents reporting and linking surveillance method and study the function of the latter. Results （1） The reporting of dead rodents contributes to, and other two plague?risk indicators reporting has no relation to the detection of commensal rodent plague among rodents.（2）The two HD techniques in monitoring and control system of commensal rodent plague are dead rodents reporting and linking surveillance method, of which, the former is mainly in charge of the detection of the plague among rodents in time, and the latter has two roles, namely both decreasing and founding the epidemic foci among rodents, especially in decreasing them. Conclusion The emphasis should be put on the popularization of 2HD technique in order to detect and control rodent plague in time in the monitoring and control of commensal rodent plague, and at the same time,  the reporting of three plague?risk indicator should be understood and treated correctly.

Objective To know deeply the incidence mechanism of commensal rodent plague and scientifically work out or choose appropriate surveillance and control measures.Methods The transmission route from rodents to humans of commensal rodent plague was expressed by mathematical language to show up the inherent relations among the decisive factors,and its relevant monitoring methods were analyzed and compared.Results(1)An incidence mode function of the plague was derived.(2) The linking surveillance method was more effective than the parallel surveillance method,and the former was more accordant with the epidemiology principles,the statistics requirements and the "benefit-cost ratio" requirement because of its smaller workload.Conclusion(1)The incidence mode function on commensal rodent plague disclosed the inherent relations among the decisive factors of the disease,and had the important guide function and wide application prospects to its prevention and control.(2)The linking surveillance method should be suited to the surveillance of plague compared to the parallel surveillance method.