ISSN 1003-8280 CN 10-1522/R 中国疾病预防控制中心 主办
Objective To develop a rapid and sensitive detection method for Batai virus (BATV) based on TaqMan Real-time PCR. Methods Based on the BATV NS gene sequences of S segment published in GenBank, BATV specific primers and probe were designed. The specificity and stability of the system were evaluated. Quantitative standard curve of BATV TaqMan Real-time PCR was established. Results The specificity and stability test showed that the system is specific and the coefficient variables were all less than 2.50%. Quantitative standard curve based on the genomic copy was drawn, and the lowest detectable limit (LOD) of system is 10 copies/μl. Conclusion TaqMan Real-time PCR for BATV detection has been developed, which is more sensitive and more efficient than the general PCR.
Objective To understand the epidemiological characteristics of imported dengue cases in Yunnan during 2004-2014, and provide the scientific information for the effective strategies of dengue control and prevention. Methods The data of imported dengue cases were collected from China Information System for Diseases Control and Prevention during 2004 to 2014. A database was established to analyze the epidemiological characteristics with method of descriptive epidemiology; dengue serotype was detected by RT-PCR.Results From 2004 to 2014, a total of imported cases were 629 (629/2 192, 28.70%) in Yunnan; The imported cases of dengue were mainly reported in Dehong Prefecture (341 cases), Xishuangbanna Prefecture (159 cases) and Kunming city (108 cases); The cases were reported every month, but 85.37% (537/629) of the cases were imported between August and November. Male cases were much more than female, 419 and 210 cases respectively. The occupations of cases mainly were business service people (165 cases), farmers (134 cases) and students (72 cases). Most cases were imported from Myanmar (403 cases) and Laos (132 cases). Four (4) dengue serotypes were found from imported cases; of those DEN-3 was the major type in those from Laos, and DEN-1 in those from Myanmar. Conclusion The imported dengue cases have been on rise in Yunnan, and their major concerns are the border areas with Laos and Myanmar. The above results suggested that colloborative efforts from various agencies should be strengthened to monitor border imported dengue cases in case of dengue outbreak.
Objective To understand the endemic situation of schistosomiasis in surveillance sites, and to provide scientific reference for schistosomiasis control during the "Thirteenth Five-Year Plan" in Zhejiang province. Methods According to the scheme of Zhejiang provincial schistosomiasis surveillance (revised in 2012), 11 provincial schistosomiasis surveillance sites which represented for water network endemic regions and hilly endemic regions were selected and evaluated. The morbidity of the infection, snail distribution and relevant factors were investigated. The 5 meter-synchronously systematic samplings combined with the environmental samplings were used for snail survey. Indirect hemagglutination assay (IHA) combined with miracidium hatching method were used to evaluate morbidity in humas. Results The residual snails area were 12 100 m2 in the 6 surveillance sites from 2012 to 2014. The area with Oncomelania snails,the rate of living snails frame and the mean densities of living snails in 2014 were reduced by 76.22%,53.04% and 73.91% when comparing to those in 2012, and no imported and infective snails were found. There were no local schistosomiasis cases, but 4 advanced schistosomiasis cases and 16 imported schistosomiasis cases were found in the surveillance sites. Conclusion The results of surveillance showed the current stable schistosomiasis endemics and the need of proper control measures in Zhejiang province. There are some residual snail populations and imported schistosomiasis cases in the surveillance sites, thus there is still a risk of re-emergence of schistosomiasis. To achieve the goal of schistosomiasis eradication, we must emphosize comprehensive prevention and control strategy with given priority to the surveillance of residual snails and imported schistosomiasis.
Objective To investigate indoor mosquito species distribution in different geographical locations and ecological environments in Hubei province. Methods Mosquitoes were captured from May to September in 2014, species and sex composition were analyzed with statistical tests. Results Five species including Culex pipiens quinquefasciatus, Cx. tritaeniorhynchus, Armigeres subalbatus, Anopheles sinensis and Aedes albopictus were captured, accounted for 46.37%, 25.99%, 15.37%, 12.14% and 0.13%, respectively. From different topographologic types, Cx. pipiens quinquefasciatus and Cx. tritaeniorhynchus were predominant in plains, Cx. pipiens quinquefasciatus, Ar. subalbatus and Cx. tritaeniorhynchus were predominant in hilly areas. From different host types, Cx. tritaeniorhynchus and Ar. subalbatus were predominant in stables, Cx. pipiens quinquefasciatus was common in birdhouses and human dwellings. Females of 5 species were captured, but males from only two species were captured including Cx. pipiens quinquefasciatus and Ar. subalbatus. Conclusion Predominant species and sex composition show significant difference among different topographical environments and host types.
Objective DNA barcoding techniques were employed to identify the unknown mouse species intercepted from the dry cassava imported from Cambodia at Zhongshan port, whose morphology was damaged too badly to be identified. Methods Genomic DNA was extracted from the intercepted mouse. Target fragments were amplified with the universal primers LCO1490 and HCO2198 for the metazoan mitochondrial cytochrome oxidaseⅠ (COⅠ), PCR products were sequenced. The sequences were blasted in the NCBI. Results The sequence homology of the DNA barcode fragment between these two samples were 99.8%, and was more than 98.5% identical to the sequence of Mus cervicolor published in NCBI. Mus cervicolor is never recorded in China before, and it was the first time to intercept this species at the Chinese port according to the references. Conclusion The intercepted mouse was M. cervicolor identified with DNA barcodes, a non-recorded species in China. DNA barcoding techniques could break the restrictions of traditional species identification depending on undamaged morphological characteristics, can improve the ability to identify the exotic species, overcome the difficult in lack of identification references and experts.
Objective To investigate tick species and abundance in different sampling seasons, and explore the ticks' molecular characteristics in Aibi Lake, Alashankou Pass, Xinjiang Uygur Autonomous Region for providing the reference for the tick classification as well as prevention and control of tick-borne diseases. Methods During April to August in 2014, questing ticks were collected by dragging-flag method, and blood feeding ticks were collected from wild and domestic animals at Hejiaoke, Wulandabusen and the naturally preserve of Aibi Lake, Xinjiang, Northwest of China. The morphological and 16S rDNA identification were carried out based on representative ticks. Results We collected 434 ticks including 392 questing ticks and 42 blood feeding ticks, which including Hyalomma asiaticum, Dermacentor marginatus, D. niveus, Rhipicephalus sanguineus, Rh. turanicus, Rh. bursa and Haemaphysalis erinacei. The predominant tick species of Aibi Lake are H. asiaticum and D. marginatus. Their peak seasons were in May (Dermacentor) and June (Hyalomma). Blast analysis of 16S rDNA indicated that D. marginatus had 96%-100% identities compared with that of the ticks from Shihezi (KF547986), and that H. asiaticum was 98%-99% identical to Yili (KF527439), while Rh. sanguineus possessed 93%-94% identities with Israel (KF219732). Conclusion Rhipicephalus turanicus and Rh. bursa for the first time were found in Aibi Lake. 16S rDNA sequence of H. erinacei was reported for the first time, and was 91% identical to H. cretica. 16S rDNA of D. marginatus, H. asiaticum and Rh. sanguineus showed genetic divergence in Aibi Lake, which conveyed us that these tick species originated from different lineages.
Objective To study the structure and feeding habits of Neoseiulus barkeri. Methods After oscillating and washing, the mite was killed with heated alcohol, then placed in the preservation solution. Mounting medium zishi was applied to the slide in the amount of 2-3 drops, and a cover glass was placed after adjusted mite posture with hair needle. The specimens were dried for identification under light microscope. Results Length of N. barkeri male body is about 310-350 μm, with light gray or light brown in color. Corniculus is long and slender, aggregated to center. The fixed digit, which has three tines, and movable digit, which has one denticulation, are approximately equal in length. The spermatodactyl is shap of "T". There are 17 pair setae on the back, all equal length except Z5 which with comb shape and slightly longer. Outer edge hair r3 and R1 are located on the back. Besides anal seta there have other 4 pair setae. The female body length is about 370-390 μm. Color and shape is similar to those in male. The chelicerae is bigger than male's but the anal plate is smaller than male's. The egg is colorless and transparent, with oval shape, and size of (80-85) μm×(60-65) μm. Each female mite preyed Caloglyphus berlesei at an average of (12.80±1.47) per day and C. berlesei eggs with an average of (17.70±1.86) per day. When prey was absence, there was a tendency of self-mutilation. Conclusion We gained certain understanding of the morphology and feeding of N. barkeri, which provide a foundation for the further study.
Objective In order to provide a foundation for the formulation of botanical rodenticide, we compared the effect of different concentrations of ricin extracts of castor beans mixed in rabbit chow on the reproductive function of the mice. Methods Healthy mature male and female mice were fed with rabbit chow that was mixed with extracts of castor beans. The palatability, ovarian and testis organ coefficients were evaluated. Testicular and ovarian histological sections were produced, the latency of birth and number of offspring was compared after experimental and control groups were paired with sexually mature males and females. Results Compared with the control group, the palatability had no statistical significance to the experiment group (♂: t=1.360, P=0.227; ♀: t=1.170, P=0.449). The testis organ coefficient of the experimental group was 4.118×10-3, the testis organ coefficient of the control group was 7.398×10-3, the coefficient of the experiment group was reduced significantly reduced (t=2.740, P=0.013). The thickness of the germinal epithelium in the experimental group was (26.55±6.11) μm, the control group was (54.35±7.14) μm, the germinal epithelium was significantly thinner as compared with the control group (t=3.160, P=0.011). The latency of birth was (7.50±0.71) d and the number of offspring was (3.80±5.22) in the experimental group 1, the latency of birth was (10.00±0.00) d and the number of offspring was (0.40±0.89) in the experimental group 3. However, the latency of birth was (2.20±1.30) d and the number of offspring was (13.50±2.97) in the control group, the latency of birth was significantly delayed (Z=1.954, P=0.049; Z=3.485, P=0.002) and the number of offspring was significantly reduced(Z=2.550, P=0.011; Z=3.424, P=0.004) in experimental group 1 and 3. The female ovarian organ coefficient was 2.218×10-3 in experimental group but 4.621×10-3, in control group. The coefficient of the experiment group was significantly reduced (t=3.980, P=0.001). The luteal maximum cross-section of the experimental group was (12 347.50±2 359.28) μm2, the control group was (19 625.47±6 612.40) μm2, the difference was significant (t=2.750, P=0.013). The latency of birth was (12.00±0.00) d and the number of offspring was (1.80±4.02) in the experimental group 2, the latency of birth was significantly delayed (Z=4.485,P=0.001)and the number of offspring was significantly reduced (Z=2.703, P=0.007) in the experimental group 2.Conclusion The antifertility effect was the most profound and palatability was satisfactory for the mice when consuming the rabbit chow that was mixed with ricin extracts of castor beans. However, further studies are warranted to address the application of castor bean extract as environmentally friendly rodenticide on farmland and woodland.
Objective In this study, we investigated the population densities and resistance to commonly used insecticides of Culex pipiens quinquefasciatus in Wuhan, Hubei province. Our results can provide new insights into field mosquito control operations. Methods According to GB/T 23797-2009, lamp traps were used to caputre mosquitoes during March to November in 2014. The larve impregnation method which is recommended by WHO, was used to determine the susceptibility of larve (LC50 with 95%CI) to deltamethrin, DDVP, DDT, propoxur and temephos. Results The population densities of Cx. pipiens quinquefasciatus throughout the year showed a single peak between May and June, the average density in stables was significantly higher than any other habitats. The LC50 values of deltamethrin, DDVP, DDT, propoxur and temephos of Cx. pipiens quinquefasciatus were 0.071 7, 0.469 9, 0.766 0, 0.941 0 and 0.000 78 mg/L, and the resistance ratio were 358.50, 151.14, 42.56,9.72 and 1.30, respectively. Conclusion Our data showed that the peak population densities of adult Cx. pipiens quinquefasciatus was between May and June in Wuhan, it is also the key month for mosquito control. Considering the prevalence of resistance to chemical insecticides among mosquitoes, integrated management should be promoted to delay the development of resistance.
Objective To investigate the mosquito species, density, and seasonality in Weishan lakes area for local mosquito and diseases control. Methods The surveillance was carried out from April to October in 2014. The adult mosquito density was monitored using carbon dioxide mosquito lamp and mosquito-oviposition trap. While the larval mosquito density was monitored by spoon method for large bodies of water and pipette method for small volumes of water (in containers). Results In total, 10 972 mosquitoes were captured in Weishan lakes area in 2014. The predominant species were Culex pipiens pallens. accounting for 78.45%, followed by Aedes albopictus and Cx. tritaeniorhynchus; Seasonal fluctuations were indicated with one peak in July. The adult mosquito density was the highest in the barn. The positive rate of mosquito larvae was the highest in residential areas. Conclusion The mosquito population was high in Weishan lakes area. The surveillance findings of mosquito density and its seasonal fluctuation can provide guidance for the prevention and control of mosquitoes and mosquito-borne diseases in local area.
Objective To detect Orientia tsutsugamushi in the blood specimens from suspect patients and get a clear understanding of the infection status in Panzhihua, Sichuan province. Methods The whole bacterial genomic DNA were extracted from 48 patients' blood specimens, which were collected from the city of Panzhihua during July to October in 2013. The sta-58 gene of O. tsutsugamushi was detected by the nested PCR (SN-PCR). The partial sta56 genes were amplified, sequenced and analyzed from two cases of SN-PCR positive specimens selected randomly. Results There were 18 SN-PCR positive specimens deteced from 48 blood specimens. The partial sta56 genes were amplified successfully from two specimens and the sequences homology was 96%. Phylogenetic analysis showed that the Panzhihua43, Panzhihua45 and some Taiwan O. tsutsugamushi Strains were in the same branch, meanwhile, in the same branch with the O. tsutsugamushi Karp as well. Conclusion We have firstly detected the O. tsutsugamushi in the blood specimens by SN-PCR in Sichuan province. The existing infection of O. tsutsugamushi in Panzhihua was confirmed by the laboratory detection. Our study indicated that part of O. tsutsugamushi disease patients in Panzhihua were infected by Karp serotype, and the O. tsutsugamushi were closely related to some Taiwan O. tsutsugamushi Strains in genetic evolution.
This article created the first record of Fannia immaculata in Jingyuan Region of Ningxia, China. The species is currently known only distributed its type locality namely Quebec, Canada. This paper describes the morphological characteristics of this species and male genitalia drawn diagram for identification.
A new species, Dasyhelea kwangyangi Nie, Yu et Bo sp. nov., was recorded, which was captured in an entry ship came from Korea at the anchorage of Qinhuangdao port. The aedeagus and parameres of the new species are closely allied to Dasyhelea nachitai Yu et Liu, 2005, but the latter is distinctly characterized by short aedeagus and apical dilation of parameres. The new species is also closely allied to Dasyhelea faciigera Kieffer, 1924, but no crena on the apical dilation of the median apophysis of parameres of the latter is significantly different from that of the new species. The type specimens are preserved in the medical insect specimens Museum, Fengtai East Street No. 20, Beijing 100071, China.
The paper reports 1 genera and 19 species of bloodsucking midges in Hongxing volcano lava area, Heilongjiang province. A new species Culioides hongxingensis Yang et Liu sp. nov. is described. This new species is closely allied to C. pallidulus Yu, 1982, but is distinctly different from the eyes with interfacetal hairs, eyes are separated by width of 3.5 facet of female C. pallidulus Yu, 1982. The new species is also similar to C. subcircumscriptus Yu, 1991, but is distinctly different from the middle of pale spot over x-vein with small dark spot, cell M1 and cell M2 without pale spot of C. subcircumscriptus Yu, 1991. Culicoides donggangensis Liu, Zhou et Wu, 2007 is recorded for the first time in Heilongjiang province. The type specimens are deposited in the Shenyang Command Center for Disease Control and Prevention (Shenyang 110034, China).
The paper reports and describes one new species Phaonia anshunensis sp. nov., which was collected from Guizhou, China and assigned to the Phaonia minuticornis-group. The type specimen of the new species was collected from Guizhou, China and is deposited in Wei Lian-meng High-Skilled Talent Innovation Studio of Anshun Center for Disease Control and Prevention, Anshun 561000, Guizhou, China.
Objective To establish a quality evaluation system of Aedes albopictus population in the laboratory. Methods A u test method was used to evaluate the quality of laboratory rearing Ae. albopictus. Results A specific quality evaluation system for Ae. albopictus has been established, which includes sample collection, wet weights data collection and processing, statistical inference. Conclusion This system can effectively evaluate the quality of Ae. albopictus, and it is of great significance to repellents' laboratory efficacy tests.
Objective To analyze malaria surveillance data of Yuanjiang county of Yunnan from 1995 to 2012. Methods Data were collected from Yuanjiang county during 1995 to 2014, including malaria cases, number of resident and mobile population febrile patient blood screening, resident malaria parasitic rate, vector population density and the other data;of those malaria case was identified by tradition microscope method, malaria vector density was investigated by human hour collection mosquito in resident houses or animal shelters, and human infected malaria antibody level was tested by indirect fluorescence antibody test. Results During 1995 to 2014, total of 6 986 malaria cases were reported, in those years the highest malaria morbidity were in 1995 (84.07/10 000, 1 531 cases) and the lowest in 2012 (0 cases); total of 209 824 febrile resident patient bloods were screened, its malaria positive rate was 3.41%; total of 26 373 mobile population febrile patient bloods were tested, its malaria positive rate was 7.65%; total of 51 540 healthy residents were investigated for malaria parasite, its positive rate was 1.56%; the indirect fluorescent antibody positive rate of malaria was 39.34%(769/1 955)in 1997 but 0(0/320) in 2012; Anopheles minimus population density declined rapidly from 1995 to 2014, in consistence with annual malaria morbidity, while that of An. sinensis declined during 1995 to 2002, but increased gradually since 2002. Conclusion Above malaria monitor results suggested that imported malaria case management of mobile population and vector monitor were needed to strengthen, in order to avoid local transmissions causing by imported cases.
Objective To explore the plague epidemiological trend of the nearly 25 years in Yushu Tibetan Autonomous Prefecture, Qinghai province, and to provide basis for implementation of the prevention and control measures. Methods Analyze the data of the human plague cases, plague surveillance and the plague foci research from 1990 to 2014 with the Excel software. Results There were 17 human plague outbreaks in 11 years out of 25 years from 1990 to 2014, 54 cases were reported, including 22 fatalities, the mortality was 40.74% (22/54). The patients were mainly distributed in the following 5 counties: Yushu, Nangqian, Qumalai, Chenduo and Zhiduo. Human plague cases occurred from May to October, the peak at July to October. The majority clinical cases were pneumonic plague (34/54, 62.96%). In 2004, pneumonic plague outbreaked in local area. Conclusion The plague epidemic situation in Yushu Tibetan Autonomous Prefecture, Qinghai province is still at high risk, the human plague in some area outbrook occasionally. So as to reduce human plague occurrence risk, while conducting the Marmot plague monitoring, the monitoring of Tibetan sheep plague should also be strengthened, and the comprehensive measures of plague prevention and control should be carried out.
Objective To better understand the situation of rickettsiae infection in agrarian children in Yili prefecture, Xinjiang Uygur Autonomous Region. Methods A total of 1 722 serum samples were collected from children aged from 6-12 years old in rural areas of Yining city, Gongliu county and Zhaosu county from August to November, 2011. Indirect immunofluorescencs antibody assay proposed by WHO was used to detect tick born Rickettsia sibirica, Ehrlichua chaffeensis, Anaplasma phagocytophilum, Coxiella burnetii and flea born Rickettsia typhi, Bartonella henselae and mite born Orientia tsutsugamushi respectively. Results A high prevalence of tick borne rickettsiae including R. sibirica, E. chaffeensis, A. phagocytophilum and C. burnetiiwere detected in 37.4% (92/246) and 29.3% (72/246), 15.4% (38/246) and 12.6% (31/246), respectively. A significant seroprevalence were detected in 15.8% (39/246) of B. henselae, 5.7% (14/246) of R. typhi, and 11.8% (29/246) of O. tsutsugamushi, respectively. Conclusion A highly seroprevalences of vector-born rickettsiae were demonstrated in agrarian children in Yili prefecture, Xinjiang Uygur Autonomous Region. Differential diagnoses of patients with unknown febrile diseases and empirical anti-rickettsia antibiotics treatment of patients with suspected rickettsia infection were needed in the local areas.
Objective To determine the species diversity and similarity analysis of Ceratopogonidae in Tianmushan, Jiulongshan, Qingliangfeng National Nature Reserve of Zhejiang province. Methods The insect net capture, Malaise capture and light trap were used to capture biting midges. The similarity analysis of biting midges was clustered by the Jaccard bivariate similar coefficient. Results In the three National Nature Reserve, 56 species of 9 genera belonging to 3 subfamilies of Ceratopogonidae were found, including 52 new record species. The similarity analysis indicates that the similarity coefficient between Tianmushan and Qingliangfeng Reserve is the highest (SI=0.24); between Jiulongshan and Tianmushan Reserve is the lower (SI=0.21); between Jiulongshan and Qingliangfeng Reserve is the lowest (SI=0.20). Conclusion This study provides reference data for species diversity of Ceratopogonidae, control of bloodsucking midge and midge-borne viral diseases. The clustering analysis indicates that the similarity coefficient is mainly related to the factors of geographic locations, weather conditions, and human activities.
Objective To investigate the aggregation characteristics of rat fleas (Xenopsylla cheopis) on Asian house rats (Rattus tanezumi) and to provide scientific basis for plague control. Methods We collected fleas from live-trapped rats and calculated two infestation indices: flea prevalence and average flea abundance. Results A total of 73 rats were trapped from four survey sites along the Lancang River in Jinghong, Yunnan, and from these rats we collected 1 169 rat fleas. There were 1 056 fleas in a single survey site called Manfeilong Reservoir Fish Fry Field, with a flea prevalence of 95.45% and an overall average flea abundance of 48.00, showing an unusually super parasitic phenomenon. Moreover, we also found that the sex ratio of the fleas in this study was male-predominant, very different from previous reports (from either field surveys or lab breeding populations). Conclusion Since high densities of rat (R. tanezumi) and flea (X. cheopis) represent an increased risk in zoonotic plague prevalence, we suggest that there is a considerable high probability in causing the human plague in Jinghong, and local government and disease control department should be highly cautious about it.
Objective To investigate the change of the characteristics of rodents before and after the water storage in the Three Gorges Reservoir. Methods Mouse traps and cages were used to detect the density of rodents in different periods of the Water Storage. Results The indoor density of rodents before water storage was 4.14%. While it was 1.67% after water storage; the outdoor density of rodents before water storage was 4.29%, and it was 1.44% after water storage. The former was higher. The indoors densities of Rattus tanezumi in recent two years were much higher than before, it was 0.84% in 2011 and was 0.77% in 2012. Conclusion The densities of rodents significantly decreased after the second water storage in the Three Gorges Reservoir. But the indoors densities of R. tanezumi in recent two years were much higher than before. Continuous monitoring of rodent populations is warranted.
Objective We monitored the adult mosquito densities during 2011 to 2014, in order to provide a reference for preventing and controling outbreaks of the Japanese encephalitis. Methods During April to November of 2011 to 2014, we used light trapping method to monitor adult mosquito density at different geographic locations and the data were analyzed using SPSS software. Results The predominant mosquito species in different habitats were different, Culex tritaeniorhynchus accounted for 91.39% in livestock shed. The predominant mosquito species in other various habitats was Cx. pipiens pallens which accounted for more than 70%. Peak season was in June, July and August. Conclusion The overall mosquito density was low in Ningbo city, we should strengthen the monitoring of mosquito density in livestock shed. We should implement mosquito management tactics in April and May before the onset of the peak mosquito density.
Objective To investigate the resistance of Blattella germanica against five insecticides and customize future application of insecticides.Methods The B. germanica used in this study were the first filial generation (F1 generation 1). The insecticide film method recommended by the World Health Organization was used to determine the median knock-down time (KT50) and the corresponding 95% confidence interval (95%CI), knock-down rate, and mortality rate of B. germanica exposed to the five commonly used insecticides and to assess the levels of resistance of B. germanica. Results The average resistance of B. germanica strains from Hankou, Hanyang and Wuchang against propoxur, ehlorpyrifos, betacypermethri and azamethiphos was 1.4-2.2, 1.5-1.7, 2.8-3.1, 2.5-2.9 fold. Its resistance against tetramethrin was beyond the test range. Conclusion It was advised to apply integrated control measures and use insecticides strategically in controlling B. germanica.
Objective To investigate the resistance of Culex pipiens quinquefasciatus larvae to six insecticides and direct future application of insecticides. Methods Mosquito larvae were collected in 2014 from 5 counties (districts) of Panzhihua city, and tested by WHO recommended larval dipping method for medium lethal concentration. Results Culex pipiens quinquefasciatus larvae collected from Panzhihua city were susceptible to fenobucarb (R/S<1), but showed various degrees of resistance to cypermethrin, permethrin and deltamethrin. The resistance ratio of Cx. pipiens quinquefasciatus larvae was 75.00 fold to beta cypermethrin, 12.40 fold to permethrin 2.50 fold to deltamethrin. Slight tolerance was indicated to temephos and DDVP where resistance ratios were 1.67 and 1.65 respectively. Conclusion It was necessary to apply integrated measures and use insecticides strategically in controlling mosquitoes.
Objective Investigation of epidemiological characteristics of one dengue outbreak in a construction site in Jieyang city, Guangdong province, and evaluation of response outcome. Methods Investigate all cases in the site by epidemiology survey methods, collect blood samples from the workers for antibody detection and nucleic acid test, and survey the density of mosquito larvae by Breteau index. Results The 22 cases in total happened within 16 d, the first case on 26th September and the last case on 12th October with a morbidity of 14.7% (22/150) on this construction site. The mosquito density was decreased after the implement of control measures and the dengue outbreak was effectively contained. The isolates of dengue virus from cases had high similarity with the isolates from Guangzhou cases by Dengue virus phylogenetic analysis. Conclusion The outbreak was caused by dengue virus type 1. The source of infection might have come from Guangzhou. Early cases were not recognized in time due to misdiagnosis which led to the spread of dengue on a construction site. The key point for the successful prevention and control of dengue fever was the timely response of governmental departments and the effective implementation of mosquito control measures.
Bartonella spp. are fastidious, gram-negative and facultative intracellular bacteria that are mainly transmitted by hematophagous arthropods and known to be involved in various zoonosis. In order to understand the research advances in genus Bartonella, we analyzed literatures of Bartonella spp. temporally, spatially and by authorship using GoPubMed, and brought together knowledge of new species and genomic characteristics that were gained in recent years. This review aims to provide information for further understanding and research on Bartonella spp.
The plague is categorized as a Class A infectious disease in China. Plague foci are widely distributed, and strains have different features and varied virulence in China. It is of great significance for deducing the sudden outbreak of plague and terrorist attack detection, with the strains of different foci for genotyping. The choice of tandem repeats loci is the key of the multiple loci vntr analysis (MLVA) classification results. This assay mainly introduces tandem repeats in Yersinia pestis genotyping in application progress, and provides a reference for other workers in genotyping.
