ISSN 1003-8280 CN 10-1522/R 中国疾病预防控制中心 主办
Objective To investigate rodents, chigger mites and Orientia tsutsugamushi on mountains and plain in Qing' an county. Methods Small mammals were trapped by snap traps in September, 2013. Rodents and their ectoparasites were collected and identified morphologically. Then the rodents were dissected under sterile conditions. DNA was extracted from the spleens, nested-PCR was performed to amplify and sequence the 56 kD type-specific antigen gene of O. tsutsugamushi from all samples collected in this area. Results A total of 107 small vertebrates including 9 species were captured. Apodemus agrarius was the predominant species in outdoor rural settlements and farmland. While Rattus norvegicus and Mus musculus were the predominant in indoor environment. Apodemus agrarius and Ap. peninsulae were the predominant species in forest areas. A total of 1 164 chigger mites were collected from small mammals, including Neotrombicula gardellai, Leptotrombidium orientalis, N. japonica, and L. subintermedium. Chigger mite index on M. rufocanus was highest (65.50), then T. triton (58.13), C. rutilus (22.86) and Eutamias sibiricus (24.00). No chigger mites were found in rural settlements and farmland far from forest. Orientia tsutsugamushi was detected from T. triton and Ap. peninsulae by nested-PCR. Conclusion The composition of the small mammals and chigger mites species is similar to those in the north of Northeast China. Orientia tsutsugamushi was firstly detected in rodents in the county. Therefore Qing' an is an new natural focus of scrub typhus and human infection should be investigated in the future.
Objective To evaluate the effect of different plant infusions on the oviposition behavior of female Aedes albopictus and analyze the chemical composition. Methods The plant infusions were made by soaking leaves of Oryza sativa, Bambusaceae and Cynodon dactylon in sterile water for different times. The oviposition preference of gravid Ae. albopictus to plant infusions was tested in laboratory and field. Gas chromatography-mass spectrometer(GC-MS) was used to detect the chemical compounds of the plant infusions. Results It was different oviposition response of Ae. albopictus laboratory colony to O. sativa, Bambusaceae and C. dactylon infusions. The average spawning rate and oviposition activity index(OAI) were 63.20%-80.20% and 0.26-0.60 in O. sativa infusion; 47.51%-86.34% and -0.05-0.76 in Bambusaceae infusion, respectively. There was no oviposition preference in C. dactylon infusions. The effect of oviposition preference was significant from 30 d(O. sativa) and 50 d(Bambusaceae)to 70 d of soaking time. The trend was that the longer soaking time, the better of attractancy effects. The infusions of O. sativa and Bambusaceae after 50 d soaking time were used to test in field. The average spawning rate and its OAI were 70.99%-96.17% and 69.52%-89.51%, 0.42-0.93 and 0.39-0.79 in O. sativa infusions and Bambusaceae infusions. The GC-MS results showed that O. sativa infusion contained 108 chemical compounds and Bambusaceae infusions with 97 compounds. Of them, there were 17 compounds whose relative percentage more than 3%. The 2, 4-bis(1, 1-dimethylethyl)-phenol and Benzaldehyde were included in all samples and had higher relative content. Conclusion The infusions of O. sativa and Bambusaceae leaf had significant effect on oviposition attractancy after soaking for certain period time,and the major chemical compounds were 2, 4-bis(1, 1-dimethylethyl)-phenol and Benzaldehyde.
Objective Investigate Wolbachia infection and diversity in Aedes albopictus from different populations of China,in order to provide baseline data for the prevention and control of mosquito-borne diseases. Methods Choosing Wolbachia surface protein gene(wsp) as reference. All wsp DNA sequences obtained through PCR and sequenced were used for comparison with those sequences downloaded from GenBank, to determine the states and types of Wolbachia that infected by Ae. albopictus. Results Eleven populations were infected with Wolbachia, which including wAlbA subgroup of A group, and wPip, wAlbB subgroup of B group. Additionally, samples from Taian and Yulin were found coinfected with A and B group. These results were further supported by phylogenetic analysis, which demonstrated that all wsp sequences were clustered into two clades, and two subclades in B group were corresponding with wPip and wAlbB. Conclusion Aedes albopictus of our country were mainly infected with wAlbA and wAlbB subgroups, which with high infect rate.
Objective To understand the current status of insecticide resistance of housefly in Beihai city of Guangxi Zhuang Autonomous Region by molecular tools. Methods The genotypes of three genes(CYP6D1, Vssc and ace) in a field population of housefly from Beihai city were detected by polymerase chain reaction-restriction fragment length polymorphism analyses, and corresponding frequencies for each genotype were recorded. Results In 63 houseflies collected from Beihai city, no homozygote for CYP6D1 resistant allele was detected, while the frequencies of susceptible homozygotes and heterozygotes were 96.83%(61/63) and 3.17%(2/63) respectively. No 1014H mutation of Vssc was observed in these samples, but 1014F mutation was present in heterozygotes in a low frequency of 6.35%(4/63). The frequency of 1014L/L(susceptible) homozygote was very high(59/63, 93.65%). In 38 individuals, we observed two ace genotypes, namely 342G/V and 342A/V, in frequencies of 5.26% and 94.74% respectively. Notably, the frequency of resistant alleles(342A and 342V) reached 97.37%. Conclusion The frequencies of resistant alleles of both CYP6D1 (1.59%) and Vssc(3.18%) were low, suggesting that pyrethroids can be used for housefly control in this area. In contrast, extremely high frequencies of resistant alleles of ace were detected in housefly samples from Beihai city, indicating that failure may occur if using organophosphates and carbamates for control of house flies in the sampling region.
Objective To explore the lethal activity of propylene glycol alginate(PGA)and its mixed liquor with beta-cypermethrin against Haemaphysalis longicornis larvae, the aim was to evaluate the potential activity of PGA on killing ticks. Methods Mixed liquor was made with the ratio between beta-cypermethrin and PGA 1:1, 1:2, 2:1. Experimental group includes these three mixed liquor, PGA and beta-cypermethrin while the control is pure water. Spray tick larvae on culture dishes with these liquor, and then observed the mortality of ticks in different time series. Results There was no significance at any time series between high dilution of beta-cypermethrin(1 000 mg/L) and low dilution of PGA(12 mg/L) (Mann-Whitney U=7, P=0.766), and between high dilution of beta-cypermethrin(250 mg/L) and low dilution of PGA (2.4 mg/L) (Mann-Whitney U=4, P=0.240). However, the early efficiency(0.5 h) of PGA was significantly lower than beta-cypermethrin(χ2=7.670, P=0.007). The efficiency at 24 h and 48 h were the same between PGA and beta-cypermethrin(χ2=3.453, P=0.063; χ2=3.560, P=0.059). The efficient of mixed liquor C(ratio between PGA and beta-cypermethrin was 1:2) was the best of all. Conclusion PGA could kill the long-horned qinghaiensis ticks larvae, but it was not quick effect. According to the result, the most efficient ratio between beta-cypermethrin and PGA was 2:1.
Objective To observe the biological characteristics of Rhipicephalus sanguineus under different laboratory conditions. Methods Rhipicephalus sanguineus were cultured at different temperature in the laboratory. The growth, development and oviposition were recorded. Results Rhipicephalus sanguineus can be preserved for long term under proper conditions, and complete a generation for about 87 d at 25℃. It cannot be preserved in the laboratory when the temperature is less than 15℃. According to the prediction of the binomial model, the developmental zero temperature is 12.7℃ and the developmental peak temperature is 28.5℃. Conclusion The biological characteristics of Rh. sanguineus have been obtained under laboratory conditions. It will provide reference for colonization and scientific experiments of Rh. sanguineus.
Objective To study the survival and reproduction of mountain,water network and lake endemic areas and density Oncomelania in water network region, and to investigate the possibility of Oncomelania which come from mountain and lake endemic areas imported to water network areas, provided scientific basics for the prevention and control of imported Oncomelania snails. Methods The experimental field was located in a water network endemic area at Xiuzhou district of Jiaxing city, Zhejiang province. The experimental field was divided into three group and located in Xiuzhou district of Jiaxing city. The snails were collected from Jinhua city of Zhejiang province(mountain endemic area), Xiuzhou district of Zhejiang province(water network endemic area)and Guichi of Anhui province(lake endemic area)which were divided into 2, 4, 6, 8, 10, 20, 40 snails each cage in low density groups, and 80, 100, 150, 200, 400, 800 snails each cage in high density groups. The snails were paired with female and male in low density groups and random grouped in high density groups. The reproduction situation was observed one year later. Results The survival rates of Oncomelania snails from mountain, water network and lake endemic areas were 17.45%, 4.95%, and 7.47%, and were 48.33%, 35.56%, and 34.44% in low density groups and were 15.84%, 3.35%, and 6.07% in high density groups,respectively. The reproduction rates of Oncomelania snails from mountain, water network and lake endemic areas were 1.99, 3.10, and 1.95, and were 14.48, 24.81, and 11.42 in low density groups and were 1.34, 1.97, and 1.46 in high density groups, respectively. The differences of survival and reproduction rates of Oncomelania snails between low and high density groups in different endemic areas were statistically significant (P<0.05). Conclusion The Oncomelania snails coming from different endemic areas could survive and reproduce in the water network regions,and there were negative correlation between survival and reproduction rates and snails density.
Objective In order to establish a method of obtaining high quality DNA templates from tiny thick-chitin arthropods without grinding or damaging morphology of the voucher specimens. Methods Tiny soil oribatid mites with thick-chitin were used as research materials. We used chitinase to digest the external chitin skeleton first,after the digestion,the individuals were treated with lysate. Amplification efficiency of the DNA barcodes were used as the indicator for DNA template quality. Working concentration and condition of chitinase were optimized. Morphology of the samples treated with or without the chitinase were compared. Results High quality DNA template could be obtained with the method we established,working concentration of chitinase was optimized to 1 mg/ml, and working time was optimized to 24 h. The morphology of oribatid mites treated with the chitinase has no obvious changes compared to the untreated ones, and could be used in the morphology species identification. Conclusion Chitinase is first applied to the digestion of chitin in the extraction of template DNA, high quality DNA could be obtained without damaging the morphological characteristics, after the extraction, the tiny arthropods could be mounted on the slides and kept as voucher specimen.
Objective The cytochrome C oxidase subunitⅠ(COⅠ) gene polymorphisms for Rattus norvegicus, was studied to provide support for the species identification of rodents from frontier port. Methods The COⅠ gene of R. norvegicus was amplified, sequenced, aligned and compared with the information on GenBank to analyze genetic polymorphism and create phylogenetic tree for R. norvegicus. Results Forty-eight COⅠ gene sequences were obtained from R. norvegicus. In this research, 605 loci were measured in each sequence, there were 587 conservative loci and 18 mutation loci, the nucleotide differences number was (2.510 000±0.000 640) on average. All of R. norvegicus in Jiangsu port background only shared one haploid type, other R. norvegicus' nucleotide polymorphism was rich. Conclusion There are species differences of the R. norvegicus in different areas, this kind of difference is related to the geographical origin.
Objective To observe the effect of different temperature on the different development stages and fecundity of Culex pipiens pallens thus to evaluate the transmission capacity during the epidemic season, in order to provide a theoretic foundation for mosquito control. Methods The changes at different development stages of mosquitoes(eggs, larvae, pupae) and gonotrophic cycle were observed at different temperatures at 10, 15, 20, 25, 30, 35, 40℃. The full developmental cycles were compared within different temperatures. Results All the stages of the mosquitoes were unable to grow at 40℃; the mosquitoes developed at 10, 15, 20, 25, 30, and 35℃, the development time were 80.87, 46.33, 31.07, 24.94, 17.11, and 14.41 d respectively. Conclusion The development time of Cx. pipiens pallens was shorter at higher temperatures. The optimal temperature for the mosquitoes to develop was between 25-30℃, higher or lower temperature suppressed the development of the mosquitoes.
Objective To investigate on mosquito species of underground garage, and to make a preliminary research on the reason and tendency of them. Methods Gathered the mosquito larva from different kinds of underground garage in December of 2013 to November of 2014, then made some specimens of male mosquito genitalia after they were reared to adults. Results Culex pipiens molestus were the only species in the closed and small underground garage. Culex pipiens molestus accounted for 54.09%(119/220) of the Cx. pipiens complex in the closed and large underground garage, while Cx. pipiens pallens accounted for 27.27%(60/220). Culex pipiens pallens accounted for 54.23%(141/260) of the Cx. pipiens complex in the half-closed underground garage, while Cx. pipiens quinquefasciatus accounted for 35.77%(93/260). Conclusion Shanghai is located in the area with both Cx. pipiens pallens and Cx. pipiens quinquefasciatus, and it's complicated of mosquito species. It's necessary to monitor tightly in order to control the mosquito-borne infectious diseases.
Objective To study the characteristics of indoor mosquitoes, community composition, diversity, and seasonality in the south of Yunnan province, and to prevent local arbovirus infectious diseases. Methods In a village of Dai in Menghai county of Xishuangbanna prefecture in the north of Yunnan province, mosquitoes were captured by overnight trapping with ovitrap light and counted by species from June to October in 2014. Results Total of 15 391 mosquitoes were captured and were classified into 16 species of 5 genus in 3 subfamilies. The predominant species were Culex tritaeniorhynchus and Anopheles sinensis, the predominant index of them were 69.62 and 49.39(D>40). The sub-predominant species were An. argyropus, Cx. pseudovishnui, Cx. fatigans, An. peditaeniatus and An. minimus, the predominant index were 33.71, 31.79, 30.11, 16.88, and 16.48, respectively(D>10). Shannon-Wiener diversity index, Simpson dominance index and Pielo evenness index were 1.47, 0.29, and 0.53, respectively. Statistically analysis found that Cx. tritaeniorhynchus and An. sinensis, Cx. pseudovishnui and An. argyropus, An. peditaeniatus and An. minimus with better fitness. The peak months of indoor mosquitoes were July, August and September. Conclusion The indoor mosquitoes species in the south of Yunnan province were rich with complicated composition of community and approximately equal distribution of the predominant species. The species density of mosquitoes was high and the peak population density lasted for an extended period of time.
Objective To monitor the adult mosquito densities from 2007 to 2015, analyzing pattern of mosquitoes' species, to provide a basic reference for mosquito control measures. Methods The light trapping method was used to monitor adult mosquito density from April to December, 2007-2015. The autoregressive integrated moving average model (ARIMA) was used to predict adult mosquito density in 2016. Results A total of 94 515 mosquitoes were captured from 2007 to 2015, with a total density of 6.48 per hour. The predominant mosquito species in different habitats were significantly different, Culex tritaeniorhynchus accounted for 50.83% in livestock shed area. The predominant mosquito species in other various habitats was Cx. pipiens quinquefasciatus which accounted for more than 51.00%. The peak season of adult mosquito during 9 years was in June, the density of mosquito was high during June to September. ARIMA(1,0,0) (2,1,1)12 was successfully established, residual sequence was tested by white-noise(P>0.05), and the R2 was 0.61. Conclusion The community composition and seasonal density fluctuation of mosquitoes in Changsha city are acquired basically and the ARIMA(1,0,0) (2,1,1)12 model is able to predict the adult mosquito density. It is suggested that we should make more effort to control mosquitoes in the countryside and take measures in April and May before the onset of the peak mosquito density.
Objective To master the condition of rodent population distribution, seasonal fluctuation, rodent density for different habitats, and to provide a basis for developing rodent control strategies. Methods The rodents density was investigated by night trapping. Two types of monitoring points were chosen in town, one in residential and the other in special industry. Two types of monitoring points chosen in village were the rural and outside. Results Totally 1 059 319 traps were placed, 1 009 744 were effective, and 18 929 rodents were captured in Liaoning province from 2006 to 2015, the average rodent density was 1.87%. The density of rodents was lower in city(1.15%) than village(2.69%), and the highest was outside the village(3.39%), followed by inside the village(1.97%), special industry(1.32%) and residential community(0.97%). The density of rodents inside the village, in special industry and residential community were decreased, but that outside the village increased. Rattus norvegicus was predominant species in Liaoning province. The rodent constituent of R. norvegicus decreased, the rodent constituent of Apodemus agrarius and Mus musculus increased, the rodent constituent of Cricetulus barabensis and Tscherskia triton remained stable. In different habitats, R. norvegicus was predominant species inside the village, in special industry and residential community, Ap. agrarius was predominant species outside the village. The rodent constituent of R. norvegicus decreased in all those different habitats, M. musculus increased, Ap. agrarius outside the village increased, C. hamster and T. triton remained stable. Conclusion The density of rodents totally deceased from 2006 to 2015, but increased in recent years. The density of rodents was lower in city than village, the prevention and control for rodent density should focus on the rural areas. In different habitats,the rodent constituent of R. norvegicus decreased, M. musculus increased, Ap. agrarius outside the village increased. According to their characteristics of different habitats, comprehensive prevention measures should be taken to reduce the rodent density, for the purpose of controlling rodent-borne diseases.
Objective Analyze and evaluate the economic burden of rabies exposure population in Zhejiang province, so as to provide a quantitative basis for health administrative departments to develop disease prevention strategies. Methods Literature retrieval and questionnaire collection were used to get the general features of the 1 471 cases of dog hurt exposure in dog hurt outpatient service from February to May, 2012. The direct medical costs, the direct medical costs and delays indirect economic burden were analyzed. Through DALY and human resources to estimate the dog hurt exposed economic burden. Results Median direct medical costs was RMB 220.42 Yuan, and the direct non-medical costs was RMB 16.24 Yuan, which transportation costs accounted 76.10% was the highest. The indirect economic burden due to the loss caused by per capita was RMB 135.96 Yuan, and particularly 72.73% of all was the families delay loss. In Zhejiang province total population, the indirect economic burden of post-exposure of rabies was RMB 77 487 000 Yuan (Delay work loss). According to the weight of different age groups, calculated the Zhejiang rabies death all the population average indirect economic burden for RMB 15 767 614.70 Yuan, which 45-60 years (46.51%) and 15-45 years (46.43%) old group were the highest percentage. Economic burden of post-exposure of rabies in Zhejiang province was RMB 400.34 Yuan per capita, of which the direct medical cost of total economic burden ratio of 59.12%, followed by the indirect economic burden caused by delays, accounted for 33.97%. If the grade Ⅲ exposures to accept human rabies immunoglobulin, so will the economic burden for the 4%-20%. Economic burden was overwhelmed. Conclusion Transportation accounts for direct and has the highest percentage of medical costs, should be reasonable to layout dog injury outpatient services, which location and quantity should satisfy a range of services. The family cost (direct economic costs and delays indirect economic burden) was higher than the social cost (death indirect economic burden). Direct economic burden, especially direct medical costs was the main source of the economic burden of post-exposure of rabies. The government should formulate relevant policies to help low-income people in cost, improve the clinic proportion, improve grade Ⅲ exposure rate of immunoglobulin injections.
Objective To analyze epidemiological characteristics of severe fever with thrombocytopenia syndrome(SFTS) cases from Dandong city in 2010-2015, and to provide basis for the prevention and control measures. Methods The laboratory-confirmed cases reported by information management system in Dandong city from 2010-2015 were analyzed through descriptive epidemiology. Results From 2010 to 2015, 101 cases of SFTS in laboratory confirmed cases were reported in Dandong city. Of these cases, 5 cases died and the mortality rate was 4.95%. The onset time of the disease was mainly from May to October,and the peak time was from June to September. The cases were distributed in 5 counties(or cities), 37 villages and towns. The prevalent area is from the mountainous and hilly regions to the plain areas. From 2010 to 2014, males, middle-aged or older persons and farmers were the main infected persons each year, and in 2015, middle-aged and young women in the countryside were frequently infected. Thirty-two cases of the disease were once ever bitten by some kind of ticks before the onset, and 2 cases were brother and sister and once had blood contact. The main symptoms were fever, body aches,headache, fatigue, nausea, abdominal pain, diarrhea and joint pain. Conclusion The onset of SFTS has obvious regional and seasonal characteristics and it was widely distributed in Dandong city. Besides, in 2015, the incidence population changed. As a result, comprehensive prevention and control measures should be taken to prevent and control the disease.
A new species of Brachypogon(Brachypogon) turpanensis Ma et Yu, sp. nov. was described from Putaogou, Turpan, Xinjiang, China. The types specimens are deposited in the Medical Entomology Collection Gallery(Fengtai East Street No. 20, Beijing 100071, China) and Xinjiang Center for Disease Control and Prevention(Urumqi 830002).
Objective To investigate mosquito species in Muangsing county of Luangmamtha province, Lao PDR, providing evident for local important arbovirus infectious diseases. Methods Adult mosquitoes were collected by light-traps method overnight, and 4th instar larvae were collected from different mosquito breeding sites, identifying them by morphological classification method. Results A total of 21 781 mosquito individuals were collected from 44 species in 11 genera, of those Culex tritaeniorhynchus and Anopheles sinensis belonged to local predominant adult species, their proportions were 54.39% and 39.28% of total collected adult mosquito respectively; 4th instar larvae rates of Armigeres flavus and Cx. mimeticus were higher than the others, their rates were 43.42% and 18.86% of total collected Ⅳ-larvae respectively. Conclusion Mosquito species were very rich in Muangsing county of Luangmamtha province, Lao PDR, and Cx. tritaeniorhynchus and An. sinensis belonged to local predominant mosquito species, the results hinted local health department should strengthen mosquito-borne infectious diseases monitoring.
Objective To investigate hibernating Aedes albopictus in Ningbo city for local mosquito and diseases control. Methods The investigation was carried out from February to March in 2016. Collecting deposition including water and mud from 11 countries, 5 kinds of habitat, 4 kinds of containers and then were incubated in laboratory. Results A total of 1 528 valid samples were collected and the Ae. albopictus positive rate was 23.36%. The Ae. albopictus positive rate of used tire, temporary water container and vegetation water containers were higher than fixed water containers. The Ae. albopictus positive rates of mountains and peninsular were higher than that of plain. By logistic regression analysis, the Ae. albopictus positive rates of tire, temporary water container and vegetation water containers were 2.623 times (95%CI:1.698-4.052), 1.968 times (95%CI:1.280-3.027), and 1.759 times (95%CI:1.046-2.958) higher than fixed water containers, respectively. The Ae. albopictus positive rates of mountains and peninsular were 1.507 times (95%CI:1.034-2.197), and 1.530 times (95%CI:1.015-2.306) higher than plain, respectively. Conclusion The Ae. albopictus positive rate of Ningbo city was high. Doing a good job in eliminating Ae. albopictus larvae and eggs in early spring, actively, can control the mosquito density throughout the year, effectively.
Objective To investigation the plague health education methods and content to meet the need of different people in Kangbao county of Hebei province, and lay a solid foundation for targeted health education and achieve better results. Methods An anonymous questionnaire was conducted to investigate 387 residents in Kangbao county. Results The targeted group's lower rates of knowing were "the treatment of sudden high fever after contact the plague animals or bite with flea"(8.56%), "Kangbao county is the plague natural foci"(20.72%), and "the symptoms of the plague patients"(28.45%). Different occupations need different ways of plague health education(χ2=105.118, P<0.01). Correspondence analysis found that farmers and broadcast,students and lectures, workers and broadcast, cadres and the micro-channel all have strong correlations. The 76.14% of farmers choose broadcast, 66.30% of students choose lectures, and the doctors prefer brochure(37.10%) and TV(37.10%). In addition to the panels, newspapers and text message, the workers like other publicities. The leaders like the other publicities except the panels. Conclusion Use radio and television primarily to strengthen the propaganda for farmers. Organize more health education lectures in school for students. For workers and cadres, take a variety of ways of health education, for example, broadcasting, WeChat and text message. Doctors, considering the professional particularity, should be trained and assessed professionally to improve their emergency relief capability.
Objective Through a typical case of brucellosis case report, analysis of its causes, provides information for disease prevention. Methods Analyze the case data, field epidemiological survey data and laboratory test results of this case. Results The rose Bengal plate agglutination is positive and the titer of standard tube agglutination test is 1:200 (++), according to the epidemiological contact history, time of onset, clinical signs and symptoms, laboratory results and case-control studies and based on "Diagnostic Criteria for Brucellosis"(WS 269-2007), diagnosis the patient was in acute stage of brucellosis. Conclusion It is necessary to strengthen the circulation of livestock inspection, immune and management work, control the source of infection in Qinghai province. Residents need to enhance and strengthen the awareness of disease prevention, and do a good job in detecting high risk population of brucellosis, the publicity and education of brucellosis is still the emphasis in future, we must increase strength in publicity and education of brucellosis to the clinical staff, and improve the level of their professional skill, make sure that the brucellosis can be detected, diagnosed, and treated early.
Objective According to the Standard Draft (Efficacy testing methods and assessment of public health insecticides-fly bait), to evaluate the field efficacy of one fly bait(Baimiedi) and verify the feasibility of the efficacy testing method. Methods Set 3 treatment groups(A, B and C) and one control group(D), compare and evaluate field efficacy of the testing bait using Rd(relative density decline rate) as the assessing criteria, according to the Standard Draft. Results After bait treatment, the Rd of 3 groups(A, B, and C) were greater than 75%(4 h) and 85%(24 h), the Rd met the standard's requirement. The flies mortality of 3 groups were 84.00% in the minimum range(30 cm). Conclusion The testing bait has an excellent field efficacy against flies, and the Standard Draft can be used as a testing method for field effect assessment of fly bait.
Objective To understand the natural focus disease dynamics among people living in the surveillance sites of Three Gorges Reservoir in Yichang city,to provide timely measures for disease control and prevention. Methods Continuously collecting and analyzing 2003-2015 surveillance natural focus disease incidence data, crowd serological data, and rodents monitoring data. Results From 2003 to 2015, Three Gorges Reservoir of Hubei Yichang section reported leptospirosis, malaria, rabies each 1 case, no plague, epidemic hemorrhagic fever, and other natural focus disease cases reported. Serological surveillance results showed that the crowd epidemic hemorrhagic fever and leptospirosis antibody positive rate were 2.22%, 14.12% respectively. Indoor rodents' density declined after rising first, outdoor rodents' density was on the decline in volatility trends. Renal leptospirosis and pulmonary hemorrhagic fever positive rate were 3.49%, 0.35% respectively. Conclusion The natural focus diseases in Three Gorges Reservoir haven't exerted great impact on population health. The disease surveillance should be continued.
Objective To investigate the epidemic status of schistosomiasis in Zhejiang province, so as to provide scientific data for the strategies for schistosomiasis control. Methods The snail survey was conducted by the method of five meter synchronously systematic samplings combined with the environmental samplings. The snails were dissected to determine the infection status and were controlled by molluscacide combined with environmental modification. Both residents, migrating population and domestic animals were screened by serological methods, and the positive cases were confirmed by miracidium hatching method. Results The snail-infestation area was 657 200 m2 in 328 villages of 94 towns in Zhejiang province in 2015. Among them, the area of 8 600 m2 was newly detected. No infection was found among 78 428 snails dissected. In total 112 800 individuals were examined by serological methods, and 679 persons were positive and the positive rate is 0.60%. No native cases or livestock were found except 8 imported cases. 1 119 advanced patients were treated and medical care provided. Conclusion The results of surveillance showed the current stable schistosomiasis endemics in Zhejiang province. However, a risk factor for re-emergence of schistosomiasis still exists. Comprehensive strategy including emphasizing on prevention and control of residual snail and import cases should be stressed in the future.
Objective The purpose of this study was to explore the relationship between incidence of hemorrhagic fever with renal syndrome (HFRS) and meteorological factors. Methods We collected HFRS epidemiological data and meteorological data from 2000 to 2014 in Anqiu city. Excel 2007 was used for summarizing data and descriptive analysis. SAS 9.2 was used for correlation analysis, multiple linear regression analysis. Results The HFRS incidence was positively associated with annual sunshine hours and the annual average wind speed. The HFRS incidence of this month was inversely associated with this month's temperature, precipitation, average pressure, average wind speed and last one and two month's temperature; but positively was associated with last two month's humidity, last month's sunshine hours and atmospheric pressure. The paper established a regression equation model for multi-analysis of relativities between weather factors and the reported incidence of HFRS. This month's sunlight(x2), last month's precipitation(x5), last two month's temperature (x8) and humidity(x9) as the independent variables, the HFRS incidence of this month as the dependent variables, the regression equation was established, y=0.019 1x2-0.014 2x5-0.239 0x8+0.061 5x9, R2=0.639. Conclusion The HFRS incidence is associated with meteorological factors which can be used to predict the incidence.
Objective To determine the real cause of this biting accident and reveal the truth of so-called poisonous mosquitoes, providing scientific evidence for control and prevention. Methods Means of epidemiology such as inquiry of medical history, field investigation were used to understand and follow up the bitten patient,and man-induced landing and catching method and identification for insect body morphology were also carried out for qualitative determination. Results The so-called mosquitoes were finally identified as members of Diptera gnats; and no blackfly activities were found anywhere near the scenic spot of Western palace; Besides, the rice field next to a blueberry garden was found to be the breeding environment of them. Actually, the inspecting density of man-induced landing method could get to the level of 13 blackflies/5 min, which caused 11 catching workers were bitten mostly on skin of lower limbs from 3-20 positions by blackflies in breeding environment, and parts of being bitten were nearly at lower limbs, ankles and acrotarsiums, symptoms were mainly characterized by severe itching, pain, redness and swelling, and it dismissed after 2 weeks. Thus, local people could prove the actual existence of blackflies and it was defined that the more lower limbs skin were exposed, the more bitten positions could be. Conclusion It is certain thing that the blackflies are definitely distributed in Qingyuan county of Lishui city, and this biting accident is clearly caused by exposure skin bites in blackfly breeding environment. In accordance, measures like strengthening publicity and education, improving individual protection and avoiding the peak season of insect activities when playing and working should be taken seriously. Moreover, further research on blackfly population, density, seasonal fluctuation, distribution, pathogen infection and understanding the season density of growth and decline, strengthening inspection and establishing comprehensive preventive measures will effectively pave the way for biting reduction by blackflies.
Cockroaches, as important vectors, affect people living and health directly. At present, cockroaches control depends on chemicals, while plant constituents attract increasing attentions in research and development because of their low toxicity and friendly environmental profile. This paper summarized reported active ingredients, activity and toxicity, as well as use for new products. Matters relevant to product development were also discussed.
The artificial medium was prepared for microbial growth, separation, and identification. The commonly used laboratory based was meat infusion agar medium, in which the trypsin digestion agar was superior. It is one of the basic conditions for the separation of Yersinia pestis, playing an important role in pathogen testing, which directly affects the quality and composition of growth, reproduction and isolation of Y. pestis. In this paper, the role of media prepared for Y. pestis, its influencing factors, various aspects of the measures were evaluated in order to constantly improve and enhance the level of quality control medium for plague monitoring.
