ISSN 1003-8280 CN 10-1522/R 中国疾病预防控制中心 主办
【Abstract】 Cockroaches are the important vectors. The aim of our paper is to understand the biology and ecology of cockroaches, and analyze the present situation of the damage of cockroaches in China. The investigation finds that the invasive species Blattella germanica has become the dominant species and its damage was increasing in urban in China. A brief review is given on the development of the equipments and methods, their advantages and limitations in the control of cockroaches. Cockroaches also play an important role in the infection and allergy. The research and control of cockroaches in China started one century ago and cockroaches control was a long?term and arduous work as facing the challenge of pesticide resistance and pesticide pollution on environment. It suggests that it should put the emphasis on environment improvement and chemical control to control cockroach, adding law and regulation control, pesticide control, biological control and genetic control, especially the rotational use of control equipment.
【Abstract】 Objective To improve the traditional preparation of the polytene chromosomes of blackflies and observe chromosomes abstracted. Methods Mature larvae of blackflies were selected, dissected and shelled out salivary glands. The traditional method was improved, and the clear polytene chromosomes slices were prepared after the use of new staining fluid, flush fluid and cleaning fluid. Results The improved method made chromosomes clearly and wholly in microscope. Conclusion The improved technique succeeded in the preparation of chromosome specimens of blackfly salivary gland, which was convenient for the observation of chromosomes shape and chromosomes variation in the laboratory.
【Abstract】 Objective To firstly investigate the diversity of mosquitoes in the six lake wetland of the northwestern Yunnan, including Qinghai Lake, Erhai Lake, Xihu Lake, Cibi Lake, Jianhu Lake and Caohai Lake. Methods During August of 2007 and 2008, adult mosquitoes were caught with UV light?traps in the Lakes or some villages near to lakes and analyzed. Results A total of 215 707 adult mosquitoes were collected and identified belonging to 2 subfamilies, 19 species and 5 genera. Among them, Culex tritaeniorhychus was the dominant species (85.54%), and Anopheles sinensis was common species (10.95%). The statistical results suggested: (1) The species of mosquitoes from Cibi Lake and Jianhu Lake were the most abundant, that from Xihu Lake and Caohai Lake was second. That from the Erhai Lake and Qinghai Lake was the minimum. From south to north, the species richness presents increase tendency. (2) Shannon?Wiener index and Pielou index in Cibi Lake and Caohai Lake were the highest, the second was Xihu Lake and Jianhu Lake. That in Erhai Lake and Qinghai Lake was the minimum. From south to north, the species diversity(H′) of mosquito showed an increase tendency, but the density(D) showed decrease tendency. The two distribution curve showed a negative correlation. Conclusion Species diversity and density of mosquito showed a negative correlation in lake wetland, and Cx.tritaeniorhychus, as dominant species, leaded the changing tendency of the diversity of mosquito. In addition, many factors such as species diversity, evenness and ecological dominance reflected the effect of artificial factors on lake wetlands and environment.
【Abstract】 Objective Study the changes of acetylcholinesterase (AChE) activity in different strains of adult male and female Culex pipiens pallens, and provide a basis for the insecticide?resistance detection of mosquitoes by biochemical method. Methods The AChE activity of single mosquito was determined, and acetythiocholine iodide (ATch) as the substrate and 5, 5′?dithio?bis (2?nitrobenzoic acid) (DTNB) as the developer. The insensitivity of AChE to Propoxur was assayed. Results The AChE activity of anti?DDVP (Rd) and anti?Propoxur (Rp) strains of Cx.pipiens pallens was significantly higher than that of susceptible (S) strains, however, the AChE activity of anti?Cypermethrin (Rc) strains was similar to that of S strain. The individual frequency of insensitive AChE of Rd strain and Rp strain was significantly higher than that of S strain, but that of Rc strains was similar to S strain. For S, Rd, Rp and Rc strains, the AChE activity of 3?day?old female mosquito was higher than that of 3?day?old male mosquito. Conclusion The resistance of mosquitoes could be judged by the determination of AChE activity, but a criterion should be different for the male and female mosquitoes.
【Abstract】 Objective To know about the mosquito density in Beijing city and Olympic venues by questionnaire. Methods Seven districts and seven Olympic venues were chosen to implement questionnaire survey by stratified random sampling. Results According to survey in the indoor environment, 92.31% of the respondents thought there were only a few mosquitoes in Beijing city, and 96.02% of the respondents thought there were few mosquitoes in Olympic venues. For the outdoor environment, there were 77.81% of the respondents who considered few mosquitoes in Beijing and 97.26% of the respondents considered that few mosquitoes was in the Olympic venues. About 69.85% of the respondents thought there were fewer mosquitoes in 2008 than in 2007 in Beijing. There were 80.60% of the respondents considered Olympic venues were good. Conclusion The mosquito density in both the indoor and outdoor environment in Olympic venues was lower than that in Beijing city, and the mosquito density in 2008 was lower than that in 2007.
【Abstract】 Objective Compare the control efficacy and control cost of two different anticoagulant rodenticides against Mongolian gerbil (Meriones unguiculatus). Methods Tests were carried out from September to October of 2007 in Abage county. The control efficacy and control cost of 4 different bait treatments methods were calculated. Results The results showed that the killing efficiency of bromadiolone poison baits to M.unguiculatus was 59.18%, increasing by 6.95% than that of sodium diphacinone (52.23%). Taking the control efficacy and control cost into account, bromadiolone poison baits put at 10 m intervals was the optimum method, and its cost was￥22.05/hm2. Conclusion Compared to sodium diphacinone, bromadiolone, with the characteristics of high?efficiency and safety, is used for the control of M.unguiculatus.
【Abstract】 Objective To understand the population composition of rat?shape rodents in Guangdong province and its breeding in different seasons, and to provide the theoretical basis for the control of rodents. Methods Rodents were caught daily by snap trap method in township sampled randomly monthly. The rodents captured were identified and dissected, recording the pregnancy situation. Results The trapping rate of rat?shape rodents was 9.98% in the residential areas, including 4.98% of rats. It included 48.73% Rattus norvegicus, 15.50% R.tanezumi mice, 35.17%Suncus murinus and 0.59% Mus musculus. The average pregnancy rate of R.norvegicus was 4.06% and the average litter size was 5.35. The average pregnancy rate of R.tanezumi was 5.63% and the average litter size was 2.76. That of Suncus murinus was 15.00% and its litter size was 3.32. Conclusion R.norvegicus and Suncus murinus are the dominant species in the residential areas in township. M.musculus is the rare specie. The breeding seasons of R.norvegicus and R.tanezumi are in spring and autumn, and the breeding peak in spring is higher than that in the autumn. It has also a small reproduction peak in August. However, Suncus murinus can breed all year round, and there are also two peaks. One peak is in March?June, the other is in October?November. It should strengthen the killing of rodents in spring and autumn.
【Abstract】 Objective To study killing effects to rodents in large reservoir region, and provide scientific basis for rodent control. Methods 0.1% sodium diphacinone was given indoor, and 0.005% Bromadiolone outdoor in the Pingban reservoir region. 0.005% Bromadiolone baits were given in the outdoors of the Baise reservoir, Ertan reservoir and Changzhou reservoir region, while 0.0375% Racumin wheat baits was taken in the indoor and outdoor of Longtan reservoir region. Results The killing rate was 83.89% in the Pingban reservoir, 83.40% in the Baise reservoir, 92.82% in the Ertan reservoir, 86.65% in the Longtan reservoir and 89.35% in the Changzhou reservoir region. Conclusion Bromadiolone and Racumin had good killing effect on rodents in reservoir region, and the integrated control measure was taken to reduce effectively the rodent density.
【Abstract】 Objective To study the population composition and quantity change of rodents in Kaijiang county, Sichuan province, so as to provide basic information for rodent control. Methods The rodents density was investigated by night trapping in the indoors and outdoors. Results The rodent density in the field was higher in 1989-1990 and 1992-1993, reaching about 18.85%-26.57% and steady in 4.21%-14.88%. The rodent density in the indoors was in the peak in 1986 (9.47%), and it was 1.96%-7.26% in other years. The rodent density in the field rodent was higher than that in the indoors. The dominant species were Apodemus agrarius (51.59%), Anourosorex squamipes (27.36%) and Rattus noregicus (18.68%) in the field. However, The dominant species in the indoors were R.norvegicus (64.32%), Mus musculus (26.58%) and An.squamipes (7.99%). The dominant species exchanged in different years. Conclusion The rodent density and its population dynamics were affected by density dependent factor and non?density dependent factor in the field, but that in the indoors was relative to the control of rodent.
【Abstract】 Objective To further explore the action mechanism of lambda?cyhalothrin by researching the effect of it to Superoxide dismutase (SOD) and Glutathione peroxidase (GPX) of Blattella germanica, and to provide theoretical basis and useful methods for the control and prevention of B.germanica. Methods Lambda?cyhalothrin with different concentrations was sprayed on B.germanica according to the method of GB 13917.1-13917.8－92, and the activities of SOD and GPX were determined by kits. Results The induction of lambda?cyhalothrin with different concentrations to SOD and GPX varied with time, and the induction effect had a positive relationship with the concentrations of lambda?cyhalothrin. The relative activities of SOD and GPX appeared the trend of “rise?decrease?rise” within 144 h. Conclusion The lower concentration of lambda?cyhalothrin has obvious induction to SOD and GPX, and the increase of SOD and GPX activity has the relationship to the resistance and tolerance of cockroach to lambda?cyhalothrin.
【Abstract】 Objective To monitor the population density and seasonal fluctuation of flies at different areas of Hebei, and compare the trapping efficacy of different baits. Methods Cage trapping method was used in this study. Results A total of 19 species were caught, belonging to 4 families, 14 genera. Musca domestica was dominant specie. Muscidae were mainly trapped with putrid fish, accounting for 54.22% of the total. Muscidae and Calliphoridae were mostly caught with a mixture of brown sugar and vinegar, accounting for 39.17% and 36.08%, respectively. The season fluctuation tendency of flies caught with two baits was similar, and the peak was all in August. Conclusion According to the surveillance data, the species controlled mainly are M.domestica, Chrysomya megacephala, Lucilia sericata, Boettcherisca peregrine and M.stabulans. Environment improvement and the reduction of bleeding sites are the basic measures to control fly density. The putrid fish is worthy to be recommended as a surveillance method of flies density.
【Abstract】 Objective To learn the resistance situation of Musca domestica from different areas in Hubei province to common insecticides and study its control measures. Methods Topical application was used in this study. Results The surveillance results indicated the average LD50 values of DDVP to housefly from different areas was 0.2256, 0.1908 and 0.4428 μg/housefly from 2005 to 2007, respectively. The average LD50 of alpha?cypermethrin was 0.0841 and 0.1102 μg/housefly in 2006 and 2007, respectively. The average LD50 of deltamethrin was 0.0371 and 0.0825 μg/housefly in 2005 and 2007, respectively. The average LD50 of etramethrin in 2005 and 2006 was 0.3952 and 0.2894 μg/housefly, respectively. The average LD50 of acetophenate in 2005 and 2007 was 0.3264 and 0. 3487 μg/housefly. Conclusion M.domestica had high resistance to organic phosphorus and pyrethrum insecticide in Hubei province. No obvious resistance against acetophenate had been found. The mixed and rotation use of insecticides contributed to the control the resistance development of M.domestica.
【Abstract】 Objective To investigate the resistance of Culex tritaeniorhynchus to insecticides used frequently in high incidence areas of Japanese encephalitis in Shaanxi province. Methods The density of mosquitoes was calculated by labor hour method. Larva death rate of five insecticides and LC50 of eight insecticides were determined by distinguishing dosage method and median lethal dose method respectively. Results The average density of Cx.tritaeniorhynchus in breeding farm was 194.91/man· hour. The mortality of mosquitoes in Nanzheng, Hanyin, Hanbin and Pingli county was 1.84％-13.65％ and 10.86％-31.25％ after treatment by DDVP and deltamethrin for 24 h. Maximum LC50 of the same insecticide in different areas was1.27-8.00 times of the minimum. Conclusion Cx.tritaeniorhynchus developed different resistance to tested insecticides in four investigation sites, except that it was susceptible to cypermethrin in Hanbin, Nanzheng county and to DDT in Pingli, Nanzheng county. Cx.tritaeniorhynchus populations had developed high resistance to DDVP and deltamethrin, moderate resistance to permethrin. Rotational or mixed use of insecticides with different action mechanisms should be adopted to postpone the development of insecticide resistance.
【Abstract】 Objective To study the resistance of Rattus rattus sladeni to anticoagulant rodenticide. Methods No?choice food test was used in this study according to the method of national rodent resistance surveillance group. Results The rodents caught in nine districts of Guangzhou were tested. The survival rate was 3.8%. The total average dosage was 30.31 mg/kg, and survival average dosage was 58.29 mg/kg. The result showed that its sensitivity to anticoagulant rodenticide was between R.tanezumi and R.norvegicus. Conclusion The anticoagulant rodenticide can be still used to the control of R.rattus sladeni. But it should strengthen the resistance surveillance, and the chemicals should be used scientifically and rationally.
【Abstract】 Objective To investigate the community structure of fleas on small mammals in eight counties of southern mountainous areas in Yunnan. Methods Small mammal hosts were captured from eight counties selected randomly in southern mountainous areas and fleas were collected from the body surface of each host. Richness (S), Shannon?Wiener’s diversity index (H′), evenness (J′) and dominance index (C′) were used to measure the community structure of fleas on the hosts. Results There were 3184 small mammals captured, which belonged to 21 species,13 genera, 5 families and 4 orders. A total of 1767 fleas were collected from the small mammal hosts and were classified into 15 species, 13 genera and 5 families. There were seven dominant small mammals like Rattus tanezumi, Mus caroli, M.pahari, R.norvegicus, Suncus murinus, R.rattus sladeni and Niniventer fulvescens, and the dominant fleas were Xenopsylla cheopis, Nosopsyllus (Nosopsyllus) wualis and Leptopsylla segnis. Conclusion There are few fleas in the southern mountainous areas of Yunnan which biodiversity is lower than that in others.
【Abstract】 Objective To investigate the population composition, density and seasonal fluctuation of vectors in Panzhihua in 2007, and to provide a scientific basis for its control. Methods Night trapping method was used for the surveillance of rodent, labor hour method for mosquito, cage?trapping for flies and sticky?paste for cockroach. Results There were 4 species 2 genera 1 family rodent. Among them, Rattus norvegicus was the dominant species, accounting for 66.13%. Mosquitoes caught belonged to 7 species 4 genera 2 sub?family, and Culex quinquefasciatus was the dominant species, accounting for 60.71%. Flies belonged to 13 species 8 genera 3 family, and Musca domestica and Lucilia ricata were the dominant species, accounting for 30.05% and the 28.05%, respectively. Cockroach belonged to 3 species 2 genera 1 family, and Blattella germanica was the dominant species, accounting for 91.86%. The total density of rodent was 0.28%, highest in the residential areas. Mosquito density was 2.29/man· hour, highest in the rural households. Flies density was 5.70 /cage, highest in the agricultural farm. Cockroaches density was 0.44/ （piece· night）, highest in the restaurants. The peak of rodents and cockroaches was in August, only one peak in the year. However, mosquitoes and flies showed two peaks, which were in June and September for mosquitoes and June and September for flies. Conclusion To master basically the population composition, density and seasonal fluctuation of vectors.
【Abstract】 Objective To assess the situation and influence factors of insecticide treatment bed net(ITN) in Yunnan malaria endemic areas and provide the measures for generalization of ITN. Methods Cross survey was used among 47 counties of Yunnan malaria endemic areas by multi?stages sampling method. Results There were 8.68% of households with ITN. The use of bed net was influenced by economic status, gender, marriage, education level, attitude to the use of ITN, malaria transmission knowledge and preventive knowledge analyzed by logistic regression analysis. Conclusion It should pay more attention to the population from poor families, woman, single and illiterate during the promotion of ITN. The use of ITN could be promoted by the transmission of malaria transmission route and preventive measures.
【Abstract】 Objective To provide the fundamental data for the control of the flea and to explore insecticidal mechanisms of fenoxycarb to the early third?instar larvae and the newly emerged adults of Monopsyllus anisus (Rothschild, 1907) through histological observations. Methods The early third instar larvae and the newly emerged adults of M.anisus were treated with fenoxycarb by microliter syringes. The changes of tissues were determined by the methods of histology, microphotographics and statistics. Results The cuticula of the third instar larvae of M.anisus treated with fenoxycarb became thicker, the ovarial rudiments augmented firstly then shrank. The testicular rudiments shrank, and the midgut epithelial cells became atrophy. The testicular plug of the newly emerged adults of M.anisus treated with fenoxycarb disappeared fast, the salivary gland cells were damaged, and the midgut epithelial cells became atrophy. Conclusion （1）Fenoxycarb can cause the death of M.anisus larvae by the disturbance of larvae metamorphosis and changes in cuticula, ovarial rudiments and testicular rudiments or midgut epithelial cells. （2）Fenoxycarb can accelerate the disappearance of testicular plug of the newly emerged male adults. （3）Fenoxycarb can lead to the death of the newly emerged adults of M.anisus by the damage of salivary gland cells and atrophy of midgut epithelial cells.
【Abstract】 Objective To extract and screen the volatile oil from Chinese crude medicines which can kill Human demodex in vitro. Methods The mites were collected with cellophane tape. The killing effect of different volatile oils to H.demodex was investigated by microscope. The Physiological saline and Xinfu Manling Ointment were selected as negative and positive controls, respectively. Results The six volatile oils of Chinese crude medicines had good killing efficiency to Demodex folliculorum and D.brevis in vitro including clore, orange, cinnamon bark, clove and so on. The killing effect of volatile oil from clore and manchurian wldginger to the D.folliculorum was better than that to D.brevis. Conclusion The six volatile oils from Chinese crude medicines had remarkable anti?mites activities in vitro.
【Abstract】 Objective To test the bioactivity of essential oil extracted from Pogostemon cablin (Blanoa) Benth against Aedes albopictus Skuse, so as to find a new kind of mosquito repellent. Methods Essential oil was extracted from P.cablin by steam distillation. The bioassay against larvae and pupae of Ae. albopictus was carried out by immersion method. The adulticidal of P.cablin against Ae.albopictus was investigated by modified flask method. The repellent activity of pure P.cablin oil to Ae. albopictus was assayed by topical bioassay method on the skin. Results (1) P.cablin oil had strong toxicity to larvae and pupae of Ae.albopictus. The LC50 values of P.cablin oil to Ⅰ, Ⅱ, Ⅲ, Ⅳ instar larvae and pupae of Ae.albopictus were 20, 34, 59, 60 and 187 μg/ml after treatment for 24 h, respectively. (2) The fumigation efficacy of P.cablin oil to adult Ae.albopictus was quick and efficient, and the KT50 values against Ae.albopictus were 14.692, 16.528 and 14.807 min at the dosages of 18, 36 and 54 μg/cm3, respectively. (3) The 100% protection time offered by P.cablin oil on the skin were (2.70±0.12) h, (4.40±0.10) h and (6.00±0.44) h at dosages of 1.5, 2.0 and 2.5 mg/cm2, respectively. Conclusion P.cablin oil has good bioactivity to Ae.albopictus, which is a kind of potential environment?friendly mosquito?repellent.
【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 detect leptospira in frogs by Dot blotting and to establish a promising technique used for epidemiological investigation and surveillance of leptospirosis. Methods A pair of flaB primer was synthesized according to the sequences of flaB from Lai strain of Leptospira icterohaemorrhagiae, and was used to amplify the flaB gene of leptospira in frog specimens collected from leptospirosis epidemic area, Anhui province. PCR products were then moved to NC membrane and hybridized with flaB probe labeled with digoxiugenin. Results The results demonstrated that only 5 fg of purified DNA of leptospira could give a positive signal by Dot blotting. There were 19 positive samples detected by Dot blotting among 70 samples of frog kidneys, and the positive rate was 27.14%. Eight samples were positive by cultivating, and the positive rate was 11.43%. A total of 14 samples detected by PCR were positive, and it was 20.00%. Conclusion Dot blotting by flaB probe labeled with DIG is a high sensitive, specific and rapid technique for epidemiological investigation of frog leptospirosis.
【Abstract】 Objective To analyze the distribution characteristics of mosquito in Yunnan province and its relationship with the arborvirus such as Japanese encephalitis (JE), and provide the scientific basis for its prevention and control. Methods Mosquitoes were collected from the residential areas and the stables of livestocks in villages at night, and bamboo forests in the day. Results A total of 158 909 adult female mosquitoes were collected, which belonged to 88 species 10 Genera, and were mainly Culex，Anopheles and Aedes, accounting for 56.66%, 25.35% and 13.88% respectively. Among them, as many as 132 081 adult mosquitoes belonging to 63 species 7 Genera were caught in the residential areas at night, in which Cx.triaeniorhynchus has the highest proportion (42.12%), followed by An.sinensis (23.31%). And 26 828 adult mosquitoes belonging to 48 species 5 Genera were caught in the field by day, and the proportion of Ae.albopictu was highest (31.89%), followed by Ae.annandalei（20.21%）. A total of 131 538 female mosquitoes that belonged to 29 species of 8 Genera were divided into 3957 groups. As a result, 81 strains of JE virus were isolated from mosquitoes (17 species 5 Genera). The virus strains isolated from Culex were the most（59 strains）accounting for 72.84%, followed by Anopheles (8 strains ) accounting for 9.88%, and Aedes (9 strains) accounting for 11.11%. Only two strains were isolated from Armigeres and Mansonia, accounting for 2.47%. About 27 strains JE were isolated from Cx.triaeniorhynchus, accounting for 33.33% of the total. Conclusion The dominant species in the residential areas are Cx.triaeniorhynchus, An. sinensis, Cx.fuscocephalus, Cx.whitmorei, Cx.pseudovishnui and An.vagus at night, while Ae.albopictus, Ae.pseudalbopict, Ae.annandalei, Ae.vexans and Ar.subalbatus were the dominant species in the field by daytime. Cx.triaeniorhynchus and Ae.albopictus are the main vectors of JE and Dengue fever in Yunnan province, respectively.
【Abstract】 Objective To clarify the natural infection situation of rodents by Hantavirus (HV) and HV strains in Zhejiang province in 2007，and provide science evidence for the prevention and control of hemorrhagic fever with renal syndrome (HFRS)．Methods Lung tissue and serum from rodent were sampled, and IgG antibody from serum was tested by indirect immunofluorscence assay and direct immunofluorscence assay was adopted to test HV antigens from lung tissues. HV was isolated by Vero?E6 cells, and HV strains were identified by Anti?McAb．Results A total of 1129 rodents were captured in 2007．The dominant specie was Apodemus agrarius, and the positive rate of HV antigen in rodent lungs was 3.0%. The IgG antibody of 57 blood samples was positive, and the positive rate was 8.0%. Six strains of hantaan (HTN) virus were isolated, five strains from A.agrarius and one from Rattus norvegicus. Conclusion There are natural foci of HFRS which main infection sources are A.agrarius in Zhejiang province, and HTN strain could be the main prevalence strains of HV.
【Abstract】 Objective To understand the pattern of epidemic areas of hemorrhagic fever with renal syndrome (HFRS) in Fujian and to provide scientific basis for its prevention and control. Methods Rats were captured in springs and autumns by live snap method, and its density and specie composition were investigated. The virus antigen from rodent lungs was isolated and identified. Results The dominant species in residential areas was Rattus norvegicus in Rattus type areas and the mixed?type area, which density were 4.91% and 5.73% at home respectively. While in the field, it was Apodemus agrarius with the average density of 12.95%, which was obviously higher in autumn and winter than that in spring. R.norvegicus mainly carried with Type Ⅱ virus, and Ap.agrarius with Type Ⅰvirus. A44 and R50 virus strain were isolated from them, respectively. Conclusion R.norvegicus was still the main host of HFRS in Fujian. Ap.agrarius was the main host in the field in the diversity epidemic area. It should strengthen the surveillance and the control of HFRS in main epidemic areas.
【Abstract】 Objective To discuss the influence factors of mice?to?mice plague in Yanchi county of Ningxia. Methods The density of field mouse was investigated by stratified sampling method. The mice were dissected and the viscera were taken out to do etiology examination by pressing culture method. The fleas collected were separated randomly into groups to do bacteriological analysis. Results During 2002-2006, the monitoring areas of Meriones unguiculatus plague accounted for 15.93% of total foci areas in Yanchi county. The average density of M.unguiculatus was 11.02/ hm2, and the infection rate of flea and the flea index were 34.17% and 0.85, respectively. Three indexes mentioned above were the highest in 2005 and 2006. There were 4633 field mice captured during 5 years, which belonged to 8 species 6 genus 4 family. Sixty eight strains of Yersinia pestis were isolated including 57 strains from 3523 mice and 11 strains from 2393 fleas (about 380 groups). Conclusion M.unguiculatus and M.meridianus are the dominant species. Dipus sagitta, D.sibirica, Cricetulus barabensis and Phoodopus roborovskii are common species, and Cricetulus migratorius and Spermophilus dauricus are the rare species. The outbreak of mice plague has the positive correlation with mice density, infection rate of flea to mice and flea index. The projects about returning farmland to forests and pastures and forbidding grazing periodically increase the outbreak frequency and risk of mice?to?mice plague in the short time in Yanchi county.
【Abstract】 Objective To understand the epidemic situation of Lyme disease and its distribution in Qinghai, and to collect the information on main vectors and main host carrying bacterium. Understand the infection level of Lyme disease to human and provide the evidence for the surveillance and control of it. Methods Lyme disease leptospira were tested by PCR, and blood serum antibody (lgG) were determined by immunfluorescence (IFA). Results A total of 1108 people were investigated, and 167 cases were positive, the average infection rate was 15.07%. The people’s average infection rate was 7.98% in the forest areas, and 21.21% in the farming. There was significant difference between them (χ2＝36.68, P＜0.001). However, there was no significant difference among different gender and age groups. The main vector was Qinghai blood tick, and the rate carrying bacterium was 23.93%. The main host was the house mouse accounting for 46.08%, which the rate of carrying bacterium was 20.59%. Conclusion Not only the infection of Lyme disease is higher, but also the infection rate is also higher in the population. The average infection level is higher than nation average level. The infection situation varies greatly in different areas because of the difference of ecologic environment, production manner and living habit. The average infection rate in the farmland is obvious higher than that in pasture areas. Qinghai blood tick is the important vector, and there is a Lyme natural foci in Qinghai.
【Abstract】 Objective To understand the background of flies at Qingdao airport, and to provide a scientific evidence for surveillance and control of medical?vector. Methods The flies were caught by cage trap at the Qingdao airport from June 2006 to May 2008. Results A total of 46 726 flies were collected, which belonged to 7 families, 47 genera and 98 species. Among them, 30 new records were found. Conclusion It is necessary to know species composition, which provides scientific evidence for the control and the finding of new records at Qingdao airport.
【Abstract】 Objective To understand species composition, migration, distribution of the host animals in the historic epidemic areas of Dongyang, and to provide the primary data for the plague prevention and control. Methods The live trap was used in this investigation. The rats caught and the fleas collected from rats were identified, and the infection rate of rats and flea index were counted. Indirect hemorrhagic assay (IHA) was used to test the plague F1 antibody. Plague pathogen was cultured in vivo by four?step testing method. Results A total of 1269 rats were captured, belonging to 1 order 2 family 6 genus 10 species. Rattus norvegieus was the dominant species of indoor rested rats, accounted for 67.57%. While Eothenomys melanogaster Cashmere predominated in the wild with a proportion of 71.72%. And the rat density indoor and outdoor was 1.42% and 2.42%, respectively. There were only 10 rats that were found to be infected by flea among 1197 rats. And 17 fleas were collected. The infection rate of fleas to rats was 0.84%, and the total index of flea was 0.01. There were 1216 serology specimens sampled, which were all negative. No plague was isolated from 1007 specimens cultured in vivo. Conclusion R.norvegieus and E.melanogaster Cashmere were the dominant species indoors and outdoors,and and Ceratophyllus anisus was the main flea. Both the flea infections rate and total flea index were all lower than the control standard precaution line of plague. No positive results were observed. So far, there is no information showing the prevalence of plague during rats in Dongyang.
【Abstract】 This paper briefly discusses the biology and ecological characteristics of host animals and vectors infected naturally by Yersinia pestis district and the time and location of first isolation in Sanjiangyuan. It is to understand the species of animals and vectors infected and the function they plays in the plague epidemiology in order to provide the basis for the prevention and control of plague in Sanjiangyuan.
【Abstract】 Objective To grasp the population distribution and seasonal fluctuation of rat?shape animals at Zhangjiagang port, and to provide the science evidence for its prevention and control. Methods Night?trapping method was used in this study. Results The rodent density was in a low level after taking integrated measure. In this survey, the average density of rat?shape animals from 2004 to 2007 was 0.10%. Mus musculus was the dominant specie, accounting for 48.42%. Rattus norvegicus and Crocidura lasiura accounted for 25.79% and 24.43%. Two peaks of density appeared in April and September, which were 0.35% and 0.31% in 2004, and two troughs appeared in December?January and June July, about under 0.05%. The density in mess and fencing was 0.13% while the density of warehouse was 0.03%. Conclusion M.musculus was the dominant specie at Zhangjiagang port, and the integrate control measures should be taken to reduce density of rat?shape animals to prevent the occurrence of infectious disease.
【Abstract】 Objective To study the natural infection situation of Angiostrongylus cantonensis in murid from Maoming city of Guangdong province. Methods The rats were caught with live trap and snap trap method and identified with microscope. The adults of A.cantonensis were examined in lungs and hearts of the rats. Results A total of 196 rats were collected, and the natural infection rate of A.cantonensis was 10.71%. The natural infection rates of A.cantonensis in Rattus norvegicus and Mus musculus were about 11.93%(21/176) and 0(0/20) respectively. Conclusion There is a high infection level of A.cantonensis in R.norvegicus in Maoming city and R.norvegicus is an important final host in this area.
【Abstract】 Objective To obtain the distribution and population density of mosquitoes in disaster area and provide scientific basis for the control of mosquitoes. Methods The wide?catching method was used to the monitoring of mosquitoes species and density in 10 tents in anxian. Results A total of 975 mosquitoes were caught in the 10 tents within 17 days, including Anopheles sinensis, An.stephensi, Culex pipiens pollens, Cx.tritaeniorhynchus, Cx.pipiens quinquefasciatus and Armigeres subalbatus. The average daily density was 5.74 per tent. Conclusion There are many kinds of mosquitoes in anxian. And the density and biting rate of Anopheles are higher than others. Furthermore, An.stephensi is monitored in this area. So, the prevention and control of mosquito?borne diseases must be done immediately.
【Abstract】 Objective To evaluate common density surveillance methods of rat, mosquito, fly and cockroach. Methods Different surveillance methods were compared from the sides of monitoring species, monitoring instruments, monitoring data, monitoring areas, and monitoring styles. Results There are differences in monitoring species, monitoring instruments, data accuracy and the applicability among different methods. Conclusion The surveillance method should be chosen according to the object of monitoring and practice condition.
