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.

There was an outbreak of enterohaemorrhagic Escherichia coli (EHEC) O104:H4 infection in Germany from May to August in 2011. It started from North Germany, soon swept across the whole country, and then spread to the rest of Europe and North America. EHEC O104:H4 infection is a new infectious disease occurring in the new century and has attracted worldwide attention due to its strong pathogenicity and fast transmission. So far the disease has not been reported in China, but with the globalization, it is necessary to understand and prevent the disease. This paper aims to review the advances in the research on EHEC O104:H4 in terms of etiology, rapid detection, pathogenesis and symptoms of associated diseases, and preventive measures.

Objective To express two specific fragments of F1 antigen (caf1-C) in Yersinia pestis and measure their immunological activity (antigen-antibody reaction). Methods The C-terminal (caf1-C) and N-terminal (caf1-N) of Caf1 (B cell epitopes) were chosen for expression. The target genes were amplified by PCR and linked to plasmid pET32a (+). The recombinant plasmid was then used to transform Escherichia coli BL21 (DE3), and the target gene expression was induced. The expression products were purified by HIS affinity chromatography, and their immunological activity (antigen-antibody reaction) was measured by Western- blot. Results The two fragments of Caf1-C (26 000) and Caf1-N (25 000) were obtained. The two recombinant proteins were in the soluble form and reacted well with antiplague serum. Conclusion The two B cell epitopes (Caf1-C and Caf1-N) of caf1 in Y. pestis were successfully expressed, laying a foundation for the identification of cross reaction with Caf1.

　　【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.

Objective To master the distribution and seasonal abundance of infected plague vectors in the two types of plague natural foci of Yunnan province. Methods To Collect and check the relevant data on plague surveillance and investigationfrom 1974 to 2006 and analyze it by SPSS 13.0 software. Results There were 8 species of natural infected plague arthropods in the plague natural focus of Rattus flavipectus, i.e. Xenopsylla cheopis and Leptopsylla segnis, et al. Of which, X.cheopis was the main vector. 618 strains of Yersinia pestis were accumulatively isolated from X.cheopis from 1982 to 2006, accounted for 92.65% of the total strains of Y.pestis isolated from fleas. There were 7 species of natural infected plague arthropods in the plague natural focus of Apodemus chevrieri such as Eothenomys miletus miletus, Neopsylla specialis specialis and Ctenophthalmus quadratus, et al. Recently, the epidemic fleas was found in Yulong couty. 14 strains of Y.pestis were respectively isolated from N.specialis specialis and Stivalius aporus from 1974 to 2006, accounted for 15.56% respectively. X.cheopis and N.specialis specialis are the respectively major plague vector of two types plague natural focus. The strains of Y.pestis isolated from fleas in R.flavipectus natural focus centralized in June to August, highest in August. The season fluctuation of vector on investigation and surveillance were in accord with the plague natural focus of A.chevrieri & E.miletus miletus, showing two peak and centralizing in April and December. Conclusion There are respective epizoological characters about distribution and season fluctuation because of different vectors in two types of plague focus.

Objective To know the population distribution of parasitical fleas on Rattus flavipectus and their seasonal variation in Yingjiang county. Methods Collect and analyze the surveillance data and the data of epidemic situation. Results Xenopsylla cheopis and Leptopsylla segnis were major parasitical fleas of R.flavipectus. The annual infection rate, total fleas index and X.cheopis index were 15.66%, 0.91 and 0.65 respectively, which decreased significantly as a whole. The seasonal variation tendency of average monthly infection rate and total fleas index was similar, which value were 26.12% and 1.47 respectively, highest in June. There were only one peak in the seasonal variation curve of X.cheopis, and it maintained a high level from May to October, especially in June (1.37 of fleas index). Conclusion To decrease the fleas index and the plague outbreak must strengthen the elimination of fleas in summer according to the population distribution of parastitical fleas and its seasonal variation.

Objective To analyze the epidemiological character and intensity of commensal rodent plague in recent over twenty years in Yunnan.Methods Collecting data of commensal rodent plague and plague patients in recent over twenty years,and using SPSS 14.0,Map Info and relative software to analyze the data.Results From 1982 to 2004,totally,46 counties/cities occurred commensal rodent plague in Yunnan.According to the epidemiological intensity,the plague areas were classified three different type areas by Hierarchical Cluster Analysis.TypeⅠ areas include 5 counties/cities: Dehong prefecture's Longchuang county,Ruili city,Luxi city,Yingjiang county and Lincang prefecture's Fengxiang district.Epidemiological intensities were 20,12,11,16,10 respectively.503 patients were founded in 29 counties,distributed mainly in type Ⅱ areas and type Ⅲ areas,especially in type Ⅱ areas.Primary host is Rattus flavipectus,and primary vector is Xenopsylla cheopis.Conclusion At present,commensal rodent plague is still active in Yunnan;Distribution of plague focus is sporadic occurrence meanwhile epidemic outbreak in some part;Commensal rodent plague showed a serious situation: re-emerging from the east to the west,from the border to the core of Yunnan.Plague is still a critical public health problem in Yunnan province.

Objective To develop a polymerase chain reaction(PCR) method to detect Yersina pestis by multiplex primers(M-PCR).Methods Four pairs of primers,originated from the genes F1(specific capsular antigen fraction 1),pla(palsminogen activator),Hms andInv encoded on the two kinds of 65×10⁶ plasmids and two chromosomal DNA,were designed and 164 strains ofc Y.pestis were amplified with multiplex primers.Results One hundred and fifty-two of 164 strains of(Y.pestis) showed positive in M-PCR.Only 12 strains of them isolated from Yunnan were negative with amplification of the Hms gene.Conclusion M-PCR method showed satisfactory sensitivity,specificity and stability for detecting and identifying Y.pestis DNA and could be used in surveillance and rapid diagnosis for plague.

Objective The paper reported the results of study on the toxiticy of cyhalothrin to Xenospylly cheopis in laboratory.Methods The residual smearing method was used.Results(1) The KT₅₀ was getting shorter with the concentration gradually creasing,and the death rates of 24 h were getting higher.(2) When the concentration of cyhalothrin were 12.50 mg/L,25.00 mg/L,50.00 mg/L and 100.00 mg/L,the KT₅₀<6 minutes,and the knock down rates of 11 minutes >(63.0%),the death rates of 24 h>84.0%.(3) When the concentration of cyhalothrin were 50.00 mg/L and 100.00 mg/L,the shoot down rates of 30 minutes in 450 days were 100% and the death rates of 24 h in 450 days >93.0%.Conclusion The toxicticy of cyhalothrin to Xenospylly cheopis is very good and cyhalothrin can be used to control the plague in field.

Objective To study the toxicity of chlorpyrifos,phoxim and dichlorvos to Xenospylly cheopis in laboratory.Methods The residual smearing method was used.Results (1) The LC₅₀ of chlorpyrifos phoxim and dichlorvos to X.cheopis were 5.961 5 mg/L,6.787 3 mg/L and 7.834 3 mg/L,respectively.(2) At the concentration of 100 and 200 mg/L,the KT₅₀ values of dichlorvos were(9.0 min) and(4.2) min and after treated for 24 hours both death rates were 100%,the KT₅₀ values of phoxim were 44.5 min and 23.6 min,the 24 hours death rates were 98.7% and 97.8%,while the death rates for chlorpyrifos tyeated 24 hours were 98.9% and 100%.(3) When at the concentration of 100 and 200 mg/L,after 18 min the knock down rates of dichlorvos were 94.5% and 100%,17 min treated the knock down rates of phoxim were 24.4% and 41.1%.(4) At the concentration of 50,100 and 200 mg/L,the 24 hours death rates for 30 days residue effect of phoxim were 0,but for dichlorvos were 0,16.7% and 31.0%.For chlorpyrifos at the concentration of 400,800 and 1 600 mg/L,after 24 hours the death rates for 210 days were 55.2%,75.0% and 96.4%.Conclusion The quick toxitocy of the three insecticides to X.cheopis is dichlorvos>phoxim>chlorpyrifos.The residue effects are low.

Objective To explore the genetic variation and typing significance of biochemical characters ofYersinia pestis isolated from P.R.China.Methods To observe the change of 336 strains of.17 ecotypes with the single colony of every strain for ferments L-maltose,L-Rhamnose,L-Arabinose,and Glycerol and reduces KNO 3 by plate method.Results There were 3 ecotypes,the Songliao Plain,the Dianmian Residential Area and the Dianxi Vertical Vale with different colonies in fermenting Glycerol,Arabinose and maltose,respectively.The remainder was steady and consistent with the past experiments.17 ecotypes of Yersinia pestis could be divided into 12 biochemical types according to the study results.Conclusion Yersinia pestis strains are steady to ferment the above carbohydrates,which have a certain sense in Yersinia pestis typing.The Dianmian Residential Area and the Dianxi Vertical Vale are likely to derive from the same ancestor.