ISSN 1003-8280 CN 10-1522/R 中国疾病预防控制中心 主办
Objective To analyze the prevalence and genotypes of Hantavirus (HV) among rodents in the epidemic areas of hemorrhagic fever with renal syndrome (HFRS) in Zhejiang province, China from 2008 to 2011. Methods Direct immunofluorescence assay and RT-PCR were used to detect the antigen and nucleic acid of HV. Mongolian gerbils and Vero-E6 cells were used to isolate viruses from the HV-positive rodents, and the M segments of HV isolates were subjected to sequence analysis. Results Apodemus agrarius was the dominant species of the rodents captured in the epidemic areas of HFRS in Zhejiang province from 2008 to 2011. Six strains of HV were isolated from the lungs of this rodent species. The sequence analysis showed that the six isolates belonged to Hantaan virus (HTNV), wherein Z521, 524, and 534 were classified as H7 subtype, and TT-27, T-43, and R88 might be classified as a new subtype. The six HV isolates showed high gene homology between them and with the strains previously isolated in Zhejiang province. Conclusion HTNV was prevalent in rodent in the epidemic areas of HFRS in Zhejiang province from 2008 to 2011.
Objective To study the safety of compound sterilant CQ-1 in chickens. Methods Sterilant baits (0, 10, 15, and 20 mg/kg) were used to feed chickens for 10 consecutive days. All test chickens were dissected after 30 days of observation. The indices, such as general signs, food consumption, body weight, egg-laying rate, and organ coefficient, of the sterilant-fed chickens were recorded and compared with those of control group. The safety of compound sterilant CQ-1 for non-target animals was evaluated. Results No obvious abnormity was observed in any of the chickens fed with the sterilant. The control group had a maximum food consumption of 0.44±0.12 g/kg, and the 3 sterilant treatment groups had significantly less food consumption than the control group. The 20 mg/kg treatment group had a pure drug consumption of 4.20±1.44 μg/kg. The 3 sterilant treatment groups had temporary decreases in body weight, while the control group had a sustained increase in body weight. The egg-laying rate decreased in the 3 sterilant treatment groups, most (down 49.3%) in the 15 mg/kg treatment group. On days 41-50, the egg-laying rate rose and returned to normal in the 3 sterilant treatment groups. No abnormal organs were found in the 3 sterilant treatment groups after dissection, and there was no significant difference in organ coefficient between the treatment groups and the control group. Conclusion Compound sterilant CQ-1 has little toxicity to chickens. Chickens do not die after being fed with the sterilant at 20 mg/kg for 10 consecutive days. Although the body weight and egg-laying rate decrease temporarily in sterilant-fed chickens, the two indices can return to normal later.
Objective To study the spatial niches of rodents in Geermu area of Qinghai province, China. Methods The rodent communities in four habitats in Geermu area were studied using Shannon-Wiener niche breadth index and Pianka's niche overlap index. Results Of the 12 species of captured rodents, Ochotona curzoniae had the highest niche breadth (0.5486), followed by Pitymys leucurus (0.4930) and P. irene (0.4591); Phodopus roborovskii, Eolagurus luteus, Rattus norvegicus, Microtus oeconomus, Mus musculus, Dipus sagitta and Euchoreutes naso had the lowest niche breadths, with an approximate value of 0. Among the 12 species of rodents, the highest niche overlap was 1, and the lowest niche overlap was 0. Conclusion There are small differences in niche breadth between the species of rodents among the dominant species or non-dominant ones, respectively in Geermu area. The rodent species with a total niche overlap show similarities in biological characteristics and ecological adaptability, while those without niche overlap are different in the use of natural resources, demonstrating no competition in resource utilization.
Objective To analyze 92 patients with tick-borne diseases in Mudanjiang Forestry Central Hospital in 2012 and investigate their demographic characteristics and the treatment capacity of this hospital, and to provide a data support for the risk assessment of tick-borne diseases in this area. Methods The clinical data of the 92 patients with tick-borne diseases, who visited Mudanjiang Forestry Central Hospital from January to September 2012, were analyzed to investigate demographic differences, admission times, co-infection, and treatment outcomes. Results Among the 92 cases, the prevalence rate of Lyme disease was the highest, followed by forest encephalitis and spotted fever; 7 (7.61%) of the 92 cases had co-infection. The time when patients went to hospital did not completely accord with the seasonal fluctuation of ticks. In this hospital, the total effective rate of treatment for tick-borne diseases was more than 91.67%. Conclusion The special hospital in this area has a good capacity of tick-borne disease treatment in Mudanjiang.
Objective To investigate the natural progression of Borrelia burgdorferi infection among the human population in some natural foci in Xinjiang, China and the genotypes of B. burgdorferi. Methods In 2006, 119 human subjects, who were randomly selected from 1390 negative cases of 1406 individuals receiving a seroepidemiological survey of B. burgdorferi infection in the summer of 2002, as well as the 16 positive cases in the 2002 survey, were included in the study. Serum samples of each individual were collected in 2002 and 2006 and examined for the IgM and IgG to B. burgdorferi by Western blot, and a questionnaire survey was performed to investigate the frequency of manifestation of Lyme disease. In addition, urine samples were collected from the 135 subjects and examined by nest PCR to amplify 5S-23S rRNA intergenic spacer of B. burgdorferi;some of the PCR positive products were sequenced to determine the genotypes of B. burgdorferi. The PCR detection results were compared with the serological test results. Results Of the 1406 serum samples in 2002, 16 (1.14%) were positive for B. burgdorferi antibodies. In the 16 positive cases, 12 were positive for IgM, 2 were positive for IgG, and 2 were positive for both IgM and IgG. In 2006, 7 (43.75%) of the 16 positive cases in 2002 became seronegative, 4 IgM-positive cases became IgG-positive, and 5 cases remained IgM-positive. Of the 119 negative cases in 2002, 58 (48.74%) became seropositive, including 14 IgM-positive cases, 25 IgG-positive cases, and 19 IgM-and IgG-positive cases, and 2 cases had a confirmed diagnosis of Lyme disease. In 2006, 67 (49.63%) of the 135 subjects were positive for B. burgdorferi antibodies, including 58 newly found cases and 9 cases that remained positive since 2002. Asymptomatic IgG positive seroconversion rate was 34.07% (46/135) (in 2002, 4 IgM-positive cases became IgG-positive; in 2006, 25 negative cases became IgG-positive and 19 negative cases became IgM-and IgG-positive, and 2 cases had a confirmed diagnosis of Lyme disease). Only 3 (2.22%) of the 135 subjects developed Lyme disease. Of the 135 urine samples, 22 (16.30%) had positive results in PCR detection. The sequence analysis of 8 PCR positive products revealed that 7 of them were B. garinii and the other was B. afzelii. Conclusion Most cases of B. burgdorferi infection are asymptomatic among the human population in the natural foci of Xinjiang, and this infection rarely results in Lyme disease. The most and second most frequent genotypes of B. burgdorferi among Xinjiang population are B. garinii and B. afzelii.
Objective To investigate the breeding of acaroid mites in room air conditioners in Wuhu, China. Methods Dust was collected from the dust screens of the cabinet air conditioners and wall-mounted air conditioners used by Wuhu residents from June to October 2012. The mites breeding in the dust were classified and identified, and the mites of each species were counted. The mite breeding rates were compared by chi-square test. Results A total of 202 dust samples were collected from the dust screens of air conditioners; 3265 mites, including 2796 acaroid mites, were detected from the dust samples, and they were identified as 18 species, 14 genera, and 6 families. The mean breeding density was 10.39 mites/g of dust, and the breeding rate was 70.79%. The mite breeding rate for the cabinet air conditioners was 58.73%, versus 76.26% for the wall-mounted air conditioners (χ2=6.442, P<0.05). Pyroglyphidae, Acaridae, and Glycyphagidae were commonly seen and accounted for 53.47%, 20.96%, and 18.13% of the total tmites, respectively. Conclusion In Wuhu, acaroid mites breed heavily in the dust screens of cabinet air conditioners and wall-mounted air conditioners, with high species diversity.
Objective To determine the toxicities of chlorfenapyr and thiamethoxam to termites (Coptotermes formosanus) and the synergistic effect of their mixtures at different ratios. Methods In the laboratory, termites were kept in contact with filter papers treated with different concentrations of termiticides (1 ml), and the mortalities of treated termites were recorded periodically. Results The mortality of termites treated with chlorfenapyr was relatively high during hours 48-72 and 72-96, while that of termites treated with thiamethoxam was relatively high during hours 24-48, 48-72, and 72-96. The termite's mortality from either termiticide was low (<10%) within 24 h. After 96 h of treatment for C. formosanus, the LC50 of chlorfenapyr was 1.854 mg/L, and that of thiamethoxam was 386.021 mg/L. When mixed at an effective component ratio of 1:(40-80), chlorfenapyr and thiamethoxam achieved a maximum synergistic effect, with co-toxicity coefficients of 1411.65 and 1767.79, respectively. Conclusion Chlorfenapyr and thiamethoxam act slowly to kill termites. The toxicity of chlorfenapyr to termites is 208 times that of thiamethoxam. Chlorfenapyr mixed with thiamethoxam at different ratios can achieve a marked synergistic effect.
Objective To investigate the prevalence of tick-borne spotted fever group Rickettsia (SFGR) in the western mountain area of Hebei province, China and to provide a scientific basis for the prevention and control of tick-borne SFGR. Methods One set of specific primers, designed according to the outer membrane protein A (OmpA) gene sequence of SFGR, were used to amplify the OmpA gene in DNA samples extracted from Haemaphysalis longicornis collected in the western mountain area of Hebei province, and the positive samples were subjected to sequencing and sequence analysis to establish the molecular phylogenetic tree. Results Of 1227 DNA samples, 91 (7.42%) were positive for SFGR. The phylogenetic analysis based on nucleotide sequence showed that all detected SFGR strains were clustered together with Candidatus Rickettsia hebeiii (accession numbers: HQ651815, HQ651817, HQ651818, HQ651819, HQ651823, and HQ651824) and Rickettsia sp. Fujian strain FUJ (accession number: AF169629); these strains had the highest homology with Candidatus R. hebeiii (99.02% ), followed by Rickettsia sp. Fujian strain FUJ (98.50%), Rickettsia sp. Suifen strain HLJ-054 (accession number: AF179362) and Rickettsia sp. Hulin strain HL-93 (accession number: AF179364) (98.13% ), and Rickettsia sp. Japanese strain YM (accession number: U43795) (97.92%). Conclusion Tick-borne SFGR is prevalent in the western mountain area of Hebei province. Preventive measures should be taken in time to protect humans and animals from this disease.
Objective To investigate the host animals and vectors of severe fever with thrombocytopenia syndrome virus (SFTSV) and to provide a scientific basis for the prevention of this infectious disease in Donghai county, Jiangsu province, China. Methods Rodents were captured by squirrel-cage method in the field and in the residential areas of the disease epidemic foci; the capture rate of rodents was calculated, and the captured rodents were identified; the heart, liver, spleen, lung, kidney and brain of each rodent were collected. The blood of local cattle, sheep, pigs, chickens and dogs were aseptically collected. Arthropods, such as mites, ticks and mosquitoes, on the cattle, sheep, pigs, chickens and dogs were collected. The SFTSV nucleic acid in the viscera of rodents and in the mites, ticks, and mosquitoes were quantified by fluorescence quantitative RT-PCR. Total antibodies to SFTSV in the sera of animals were detected by double-antigen sandwich ELISA. Results There were six major species of rodents in Donghai county, Jiangsu province, China, i.e., Apodemus agrarius, Large hamsters, Little hamsters, Crocidura lasiura, Rattus norvegicus and Mus musculus. The capture rate of wild rodents was relatively high (13.47%), with A. agrarius as the major species, while the capture rate of house rodents was relatively low (6.98%), with M. musculus and R. norvegicus as the major species. All rodents were infected with SFTSV to different extents. Among wild rodents, the SFTSV infection rate was the highest in the liver (31.57%, 6/19), followed by the heart and lung (21.05%, 4/19), the kidney, spleen, and brain (10.53%, 2/19). Among house rodents, SFTSV nucleic acid was detected only in the heart and brain, and there was a single organ affected in any infected individual. The total SFTSV infection rates in cattle and chickens were 4.55% and 1.54%, respectively. Among arthropods, Leptotrombidium scutellare and Laelaps echidninus also carried SFTSV, but SFTSV nucleic acid was not detected in ticks and mosquitoes. Conclusion Rodents, cattle, chickens, L. scutellare, and L. echidninus may be the host animals or vectors of SFTSV in Donghai county.
Objective To investigate the prevalence of malaria at the National Malaria Monitoring Points (NMMPs) in Guangxi Zhuang Autonomous Region, China, and its determinant factors and to provide a basis for the development of preventive measures for malaria. Methods Information was collected at three NMMPs in Guangxi; the information included the blood test results of fever patients in local residents and mobile population, the immunological detection results for malaria among students at the monitoring points, the investigation of malaria vector Anopheles, and the use of mosquito nets, screened doors and windows, and insecticides among local residents. Results In 2010, there were 2348 person-times of blood tests at the three NMMPs among the fever patients in towns, with a blood test rate of 2.24% (2348/104 861); the blood test rates were 1.98% (2075/104 861) among local residents with fever and 0.26% (273/104 861) among the mobile population with fever. No malaria-positive cases were found. Anopheles sinensis was the dominant malaria vector species; the density ratios of An. sinensis were 99.94% outdoors and 100% indoors; the human-biting rate of An. sinensis was up to 49.75 mosquitoes/person·night in July. Conclusion The population density of malaria vector An. sinensis is still high. Strengthening malaria surveillance and management in the mobile population is the key to consolidating the prevention and control of malaria.
Objective To investigate the degree and characteristics of Blattella germanica infestation in the restaurants of Tianjin, China and the influential factors, and to provide a scientific basis for the development of cockroach control measures. Methods The infestation rate, population density, and density index of B. germanica were monitored using sticky traps in 540 restaurants in 18 counties or districts of Tianjin. Results The mean infestation rate of B. germanica in the restaurants of Tianjin was 43.9%, and the mean population density and density index were 3.7 individuals/trap and 20.6 individuals/room, respectively. The population density of B. germanica was relatively high in the operating room, cold meat room, pastry room, and food warehouse, where the refrigerator radiator, dressing storage cabinet, and repository of pastry materials and sweets were the main places infested. The infestation rates of B. germanica in urban areas and villages/towns were 43.0% and 44.8%, respectively, without significant difference between them (P>0.05). The infestation rates of B. germanica in small and medium-sized restaurants and large restaurants were 43.4% and 45.1%, respectively, without significant difference between them (P>0.05). The infestation rates of B. germanica in restaurants with an operating period less than 5 years, restaurants with an operating period of 5-10 years, and restaurants with an operating period greater than 10 years were 33.9%, 57.6%, and 56.9%, respectively, with significant differences between them (P<0.01). The univariate logistic regression analysis showed that the operating period was an influential factor for the infestation rate of B. germanica in restaurants (OR=1.833, P<0.05). Conclusion The restaurants in Tianjin are heavily infested with B. germanica, so surveillance and early control should be enhanced, particularly at the refrigerator radiator, dressing storage cabinet, and repository of pastry materials and sweets in operating room, cold meat room, pastry room, and food warehouse.
Objective To investigate the mosquito infestations in different schools in the central urban area of Shanghai, China and to assess the risk of mosquito-borne diseases among the students. Methods Five nurseries,4 primary schools, and 3 secondary schools in Huangpu district of Shanghai were randomly selected for investigation. The mosquito infestations in the nurseries and schools in June and August 2012 were evaluated by investigation of mosquito breeding sites and human-baited trapping. Results The mean densities of Aedes albopictus in nurseries, primary schools, and secondary schools were significantly higher in August than in June (0.25 vs. 0 mosquito/30 min·monitoring point; 3.67 vs. 0.92 mosquitoes/30 min·monitoring point; 0.11 vs. 0.06 mosquito/30 min·monitoring point, with over 100% increases when comparing the former with the latter in each pair). In August, the densities of adult mosquitoes in nurseries and primary schools were 0.45 and 3.67 mosquitoes/30 min· monitoring point, respectively; there were also increases in the positive rates of small ponded waters as breeding sites in nurseries and primary and secondary schools (47.1% vs. 16.7%; 34.5% vs. 28.6%), and the positive rate increased significantly in nurseries (χ2=3.970, P=0.046). Conclusion The indices of mosquito infestation and numbers of mosquito breeding sites per school in the central urban area of Shanghai are significantly higher than the local standards, and they show significant increases in summer. It is recommended that the education sector and schools should enhance environmental management in campus and ensure the health of teachers and students.
Objective To observe the impact of water quality on the capacity of mosq-ovitrap for monitoring the density of Aedes albopictus and to evaluate the practical value of this monitoring method. Methods During July to August 2012, the peak season of Ae. albopictus, mosq-ovitraps were set in the garden of a hospital in Shenzhen, China to capture Ae. albopictus adults and eggs, and their capacities for capturing Ae. albopictus adults and eggs were compared. Results A total of 240 mosq-ovitraps were set, and 230 were recovered. The oviposition rate was 37.39%; the mosquito-trap rate was 18.26%; 51.16% of adult mosquitoes escaped. The oviposition rate was significantly higher in water from natural environment than in bottled mineral water (χ2=13.79, P<0.01). Using larva hatching as an indicator of positive oviposition response, there was a high similarity between the oviposition rate of Ae. albopictus determined using mosq-ovitraps and the actual oviposition rate (Kappa=0.828, P<0.01). The sensitivity and specificity of mosq-ovitraps for monitoring oviposition of Ae. albopictus were 82.56% and 97.92%, respectively, with a mean area under the ROC of 0.902 (range, 0.853-0.952). Conclusion Mosq-ovitrap has a good performance in monitoring the oviposition of Ae. albopictus, but its capacity for capturing adult Ae. albopictus is not satisfactory. Water quality has an impact on the performance of mosq-ovitrap in monitoring Ae. albopictus. Mosq-ovitrap has a good practical value in monitoring the oviposition of Ae. albopictus.
Objective To investigate the attractive effects of different concentrations of lactic acid, enanthic acid, methacrylate, trimethylindole, and dimethyl disulfide on Musca domestica. Methods Lactic acid, enanthic acid, methacrylate, trimethylindole, and dimethyl disulfide were separately diluted with corn flour to different concentrations, and these compounds were put in the bait trays of mosquito-fly traps. The traps were placed in a mosquito net to capture adult M. domestica. Results Compared with controls, 0.1 and 1.0 mg/kg lactic acid led to 50.0% and 53.0% increases in number of captured houseflies, 0.1 and 1.0 mg/kg enanthic acid led to 210.7% and 77.7% increases in number of captured houseflies, 1000.0 mg/kg methacrylate led to a 155.1% increase in number of captured houseflies, 1.0 and 10.0 mg/kg trimethylindole led to 81.6% and 139.8% increases in number of captured houseflies, and 10.0 and 100.0 mg/kg dimethyl disulfide led to 137.3% and 168.7% increases in number of captured houseflies. Conclusion Considering the attractive effect and compound odor, lactic acid and enanthic acid may be used as the components of bait for indoor housefly control, and methacrylate, trimethylindole, and dimethyl disulfide may be used as the components of bait for outdoor housefly control.
Objective To establish a graded early warning system for dengue fever and assess its effect of early warning and to reduce the risk of dengue fever outbreak in Zhongshan, China. Methods A graded early warning system for dengue fever was established based on relevant literature and the data of vector surveillance and human case surveillance in Zhongshan from 1990 to 2007. The system was used for graded early warning in Zhongshan from 2008 to 2011. The outbreak scales before and after the system was established were compared based on the data on dengue fever outbreaks in Zhongshan from 1990 to 2011 to assess the graded early warning system. Results The graded early warning system for dengue fever was established according to the following indices: mosquito and oviposition positive index (MOI), human cases, and month of year; the system divided the probability of dengue fever outbreak into 5 grades, i.e., 0: almost no probability; 1: little probability; 2: probability; 3: high probability; 4: outbreak. The system sent grade 2 early warning signals 5 times, grade 3 early warning signals twice, and grade 4 early warning signals once from 2008 to 2011. From 2008 to 2011, there was only one outbreak of dengue fever involving 3 (1.20%) of 250 persons, which lasted for 20 d; from 1990 to 2007, there were 7 outbreaks of dengue fever involving 14-195 (median, 37) (0.84%-14.88%, median 3.81%) of all individuals, which lasted for 16-64 d (median, 42 d). Conclusion After the graded early warning system for dengue fever was established, the outbreak scale of dengue fever decreased significantly during 2008-2011, as compared with those during 1990-2007. The graded early warning system plays an important role in reducing the risk of dengue fever outbreak in Zhongshan.
Objective To perform various forms of intervention, investigate the effective model and method of health education for rodent control in community, and evaluate the intervention effect, and to provide a basis for proper education measures for rodent control in community. Methods One or two communities were selected from each of 4 subdistricts in Jiang'an district and Jiang'han district of Wuhan, China by stratified cluster sampling; 7 communities were selected, and the residents in the 7 communities were divided into experimental group and control group. The individuals above 18 years of age were selected from each group to undergo knowledge-attitude-practice questionnaire survey. Various health intervention measures were performed on the experimental group. The intervention effect was evaluated by comparison. Results In the experimental group, the proportion of residents with the knowledge of rodent control and related information increased after intervention (P<0.05), and the changes were significant in terms of most items in the questionnaire (P<0.05). The density of rodents, as measured by night trapping method, were 4.5% before intervention and 0.8% after intervention (P<0.01). Conclusion During rodent control in community, various health education activities, as well as management for public environment and active cooperation between people in community, can increase the knowledge of rodent control among residents and in turn improve the effect of rodent control.
Objective To investigate the species of bloodsucking midges in Xunke county, Heilongjiang province, China. Methods Light traps and insect nets were used to capture bloodsucking midges. Results A total 7810 bloodsucking midges (16 species, one genus) were captured in Xunke county, and female Culicoides xunkeensis Yang, Li et Liu, 2011 was newly found. Conclusion This investigation provides a basis for the study on species of bloodsucking midges in Xunke county, Heilongjiang province. The specimens are deposited in the Xunke Entry-Exit Inspection and Quarantine Bureau.
Flies were captured by cage trap method in 2008. Among the captured flies, there was a new record species of Calyptratae flies in Hainan province, China, i.e., Synthesiomyia nudiseta (Wulp, 1883) (Diptera: Muscidae).
Objective To observe the killing effects of 0.05% diphacinone sodium in the form of wax-coated poison bait corn granules, wax-coated poison bait wheat granules, or wax-coated poison bait mixed granules on Rattus norvegicus and Mus musculus in rooms. Methods A total of 760 rooms (around 15 m2 every room) were selected from the area with centralized residence in Zhangma Village, Jinan, China; wax-coated poison bait mixed granules were placed in 249 rooms, wax-coated poison bait corn granules were placed in 267 rooms, and wax-coated poison bait wheat granules were placed in 244 rooms. In each room, 3 piles of wax-coated poison bait (10 g/pile) were placed for 4 d, and observation was performed for 26 d. The killing effect of wax-coated poison bait was evaluated by grid/plate method (S400). Results The killing rates of wax-coated poison bait mixed granules and wax-coated poison bait corn granules were 97.45% vs. 92.44% (u=5.22, P<0.01) for R. norvegicus and were 100% vs. 99.47% (u=1.46, P>0.05) for M. musculus. The killing rates of wax-coated poison bait mixed granules and wax-coated poison bait wheat granules were 97.45% vs. 96.59% (u=1.19, P>0.05) for R. norvegicus and were both 100% for M. musculus. Conclusion Wax-coated poison bait has good killing effects on R. norvegicus and M. musculus. Wax-coated poison bait mixed granules, which are composed of wax-coated poison bait corn granules and wax-coated poison bait wheat granules at a ratio of 7:3, have a better killing effect on R. norvegicus than wax-coated poison bait corn granules.
Objective To analyze the monitoring results of rodents in Qinling Mountains in Baoji, China and investigate the population distribution and virus carriage of rodents in this area, and to provide a basis for the control of rodents and rodent-borne diseases in Baoji. Methods Night trapping method was used to capture rodents in 6 ecological environments in Qinling Mountains, including broad-leaved mixed forest, valley, peach forest, and fallow land. Results A total of 164 wild rodents (9 species) were captured, with different populations in different ecological environments at different altitudes. In the valley and arable land below 1850 m above sea level, Apodemus agrarius was the dominant species, accounting for 54.23% (77/142) of all captured rodents, followed by A. peninsulae, accounting for 16.20% (23/142). In the mixed coniferous and broad-leaved forest with an altitude above 1850 m, A. chevrieri was the dominant species, accounting for 72.73% (16/22) of all captured rodents, followed by A. peninsulae, accounting for 18.18% (4/22). Of all captured rodents, 17.81% carried viruses; among the positive rodents, hemorrhagic fever with renal syndrome (HFRS) virus was first detected from an individual of A. peninsulae besides A. agrarius. Conclusion There are a variety of rodents as vectors in Qinling Mountains in Baoji, with different populations at different altitudes, which is almost in accordance with the incidence of HFRS.
Objective To investigate the species composition of murine-like animals in the Macheng city, Yingshan county, Suizhou city, Xian'an district, Chongyang county, and Xingshan county of Hubei province, China, where there has been high incidence of severe fever with thrombocytopenia syndrome (SFTS), and to provide a scientific basis for the control of this disease. Methods The night trapping method was used to capture murine-like animals. Results Niviventer confucianus was the dominant species outdoors in Guangshui county and Sui county of Suizhou city, accounting for 58.88% of all captured rodents in this area. N. confucianus was the dominant species in Xian'an district, accounting for 68.18% of all captured rodents in this area. Crocidura attenuata was the dominant species in Macheng city and Xingshan county, accounting for 40.48% and 66.67%, respectively, of all captured rodents in local areas. Rattus tanezumi was the dominant species in Yingshan county and Chongyang county, accounting for 43.75% and 47.06%, respectively, of all captured rodents in local areas. Most of captured rodents were female. Conclusion The species composition of outdoor rodents varies greatly between the epidemic areas of SFTS in Hubei province, with N. confucianus, R. tanezumi, and C. attenuata as the dominant species, and most of the captured rodents are female.
Objective To establish an evaluation system for biological vector control in community by scientific research and to accurately evaluate and promote the biological vector control in community. Methods Delphi method was used; 10 experts in biological vector control were invited to be consulted three rounds, and they screened various indices of evaluation system and made assignment for three levels of indices. Results All consulting questionnaires were returned, and over 60% of contents were modified. Three first-level indices, 12 second-level indices, and 35 third-level indices were determined. Conclusion A high-quality evaluation system for biological vector control in community has been primarily established.
Objective To investigate the breeding situation of mosquito larvae in the urban area of Shijiazhuang, China and to provide scientific evidence for mosquito control. Methods Direct observation was used to investigate the breeding of mosquitoes in small collected waters and container waters, and visual observation combined with scoop sampling were used to investigate the breeding of mosquitoes in large and medium-sized water bodies. Water containing mosquito larvae or mosquito larvae in water were collected and taken back to the laboratory to be classified. Results The mean positive rate was 10.94% in the large and medium-sized water bodies, such as square fountains, park landscape waters (artificial lake), and Minxin River, while 221 positive sites were found in 1120 small collected waters and container waters, with a mean positive rate of 19.73% (6.35%-38.46%). The dominant species were Aedes albopictus and Culex pipiens pallens, accounting for 42.74% and 35.55%, respectively. Conclusion Mosquito control strategy should be varied with the different chacateristics of various breeding places.
Objective To investigate the population and distribution of cockroaches in Wenzhou, China. Methods The density of cockroaches was monitored by sticky-trap method in different areas and industries to analyze the population, distribution, and seasonal fluctuation of cockroaches. Results Blattella germanica was the dominant species of cockroaches indoors in Wenzhou, accounting for 97.91% of all cockroaches. For industry, the density of cockroaches was the highest in restaurants (4.28 cockroaches/trap) and farmers'markets (3.33 cockroaches/trap). For area, the density of cockroaches was the highest in Dongtou Island (5.13 cockroaches/trap). The density of cockroaches reached the peak level in June and November. Conclusion Cockroach infestation is severe indoors in Wenzhou. It is necessary to enhance the monitoring and control of cockroaches.
Objective To analyze the imported chikungunya fever cases detected at the frontier ports of Guangdong Entry-Exit Inspection and Quarantine Bureau and to provide a basis for control of imported infectious diseases. Methods Surveillance was conducted in the entry passengers at the frontier ports of Guangdong Entry-Exit Inspection and Quarantine Bureau from 2008 to 2011, and epidemiological investigation was carried out in the feverish passengers from the epidemic area of chikungunya fever. The blood samples of suspected cases were collected for laboratory test, and the information of positive cases were analyzed. Results Eleven cases of chikungunya fever, all from the epidemic area of chikungunya fever, were detected; of these imported cases, 9 were in the period of disease while passing the frontier ports, and the other 2 were in incubation period and had an onset in the observation period after entry. The mean age of the 11 cases was 40.2 years; most of them were young and middle-aged males. The primary detection method was fever surveillance. There were no secondary cases. Conclusion Control measures against chikungunya fever are properly taken by Guangdong Entry-Exit Inspection and Surveillance Bureau at frontier ports, thus effectively preventing the transmission of chikungunya virus through frontier ports.
Objective To investigate the epidemic situation of hemorrhagic fever with renal syndrome (HFRS) in Fujian province, China and to provide a scientific basis for the prevention and control of this disease. Methods The data on the epidemic situation of HFRS in Fujian province were subjected to statistical analysis. Rodents were captured using cages at night. The density of captured rodents was calculated, and their species were identified. Hantavirus antigen was detected and identified from rodent lungs by indirect immunofluorescence assay. Results A total of 259 cases of HFRS were reported in Fujian in 2011, with an incidence of 0.70/105. The cases were distributed in 64 counties, county-level cities, or districts, particularly in Nanping, Ningde, Fuzhou, and Quanzhou. The incidence of HFRS was the highest in Songxi county and Zhouning county. The surveillance of rodents showed that the mean density of rodents was 8.22% indoors, and Rattus norvegicus, which carried Soul virus (typeⅡ), was the dominant species. In the mixed epidemic area, the mean density of rodents was 6.53% in the field, and R. fulvescens was the dominant species, followed by Apodemus agrarius, which carried Hantaan virus (type Ⅰ). HFRS virus antigen was first detected from R. norvegicus in Dehua county. Conclusion R. norvegicus is still the main host animal of HFRS in Fujian, and A. agrarius is the main host of HFRS in the field of mixed epidemic area in the northeastern area of Fujian. In 2011, the incidence of HFRS in Fujian increased significantly, especially in Songxi county and Zhouning county. Rodent control should be well performed, and HFRS bivalent vaccine should be widely used among the high-risk population, so as to reduce the incidence and prevent the outbreak of HFRS.
Objective To investigate the epidemic situation, prevalence, epidemic trend, and control of human brucellosis in Shaya county of Aksu Prefecture, Xinjiang Uyghur Autonomous Region, China. Methods Different groups of people over 6 years of age were selected by stratified sampling in the study. Blood samples were collected from the individuals with suspicious clinical symptoms and in close contact with livestock to perform laboratory test. Positive rate and prevalence rate were compared between groups by chi-square test. Results A total of 4003 subjects were investigated, and 1903 of them underwent serological testing. Through three years, the mean positive rate in blood tests was 1.52%, and the mean prevalence rate was 0.45%. Veterinarians had the highest positive rate in blood tests (2.86%) and prevalence rate (2.36%). Conclusion Sheep is the source of infection of brucellosis in Shaya county. Omission of cases often occurs. Epidemiological investigation and serological testing can be performed by standard tube agglutination test and Rose Bengal plate test.
Prophenoloxidase-activating system is an important part in the immune system of Musca domestica and plays an essential role in the pathogen recognition and immune defense. Until now, however, the key genes in the prophenoloxidase-activating system and the system's action mechanism remain unclear. On this occasion, we performed transcriptomic analysis of M. domestica to obtain a number of expressed sequence tags of the key genes of prophenoloxidases, prophenoloxidase-activating enzymes, serine proteinase inhibitors (Serpin), and upstream pattern-recognition receptors in the prophenoloxidase-activating system. This article reviews the research advances in the key genes in the prophenoloxidase-activating system of M. domestica.
Currently, the use of synthetic chemicals to control insects and arthropods has caused environmental pollution and harm to human health. An alternative is to use natural products which have good insecticidal effects and are environment-friendly. Essential oils (EOs) extracted from various plants as valuable natural resources have been extensively tested to assess their repellent properties. Among the plants that hold promise as the source of EOs as repellents, Cymbopogon spp., Ocimum spp., and Eucalyptus spp. are most widely used. This article mainly reviews the repellent activity of EOs on haematophagous arthropods, the relationship between oil components and repellent activity, and the synergistic effect of their components.
Objective To design and build sanitation infrastructure in rural areas and to effectively control vector breeding. Methods The sanitation infrastructure, suitable for vector management of mosquito, rodent, fly, cockroach, and offensive odor in rural areas, was designed and built to control vectors in rural areas and improve the quality of living environment for farmers. Results The field monitoring of 2198 villages and 20 towns in Guangdong province, China, where the sanitation infrastructure was built, showed that the population densities of mosquitoes, commensal rodent, flies, and cockroaches decreased by more than 90%, and over 95% of the residents were satisfied with the sanitary environment. Conclusion In rural areas, the construction of sanitation infrastructure for vector management has the advantages of low investment and quick and good effect and is welcome to residents. It is suitable for widespread use in developing rural areas.
