1.Experimental observation of toxic effect of Bacillus thuringiensis var. israelen-sis against Aedes,Culex and Anopheles larvae
Julin LI ; Guoding ZHU ; Huayun ZHOU ; Jianxia TANG ; Jun CAO
Chinese Journal of Schistosomiasis Control 2014;(1):67-68
Objective To evaluate the toxic effect of Bacillus thuringiensis var. israelensis(Bti)wettable powder against Ae-des,Culex and Anopheles larvae. Methods The biological assay was applied to test the lethal concentration of 50%(LC50)of Bti wettable powder against Aedes,Culex and Anopheles larvae. Results The LC50(s) of Bti wettable powder against Aedes albopictus, Culex pipiens pallens and Anopheles sinensis larvae were 0.104,0.160μg/ml and 0.324μg/ml,respectively;its biological poten-cies against them were 0.125,0.192 IU/ml and 0.389 IU/ml,respectively. The LC50(s) of continuous contact of Bti wettable powder with An. sinensis stageⅢlarvae for 1,2 d and 3 d were 0.324,0.092μg/ml and 0.032μg/ml,respectively,and its biological po-tencies were 0.389,0.110 IU/ml and 0.038 IU/ml,respectively. The LC50(s) of the bacteria against An. sinensis stageⅠ,Ⅱ,Ⅲ,Ⅳwere 0.024,0.137,0.324 μg/ml and 0.450 μg/ml,respectively,and the biological potencies were 0.029,0.164,0.389 IU/ml and 0.540 IU/ml,respectively. Conclusion Bti wettable powder has a good toxicity to Aedes,Culex and Anopheles larvae,espe-cially for the latter two. It is better to apply the bacteria at the early stage of mosquito larvae.
2.Effect of different temperatures on development of Aedes albopictus
Julin LI ; Guoding ZHU ; Huayun ZHOU ; Jianxia TANG ; Jun CAO
Chinese Journal of Schistosomiasis Control 2015;(1):59-61
Objective To explore the effect of different temperatures on the different development stages of Aedes albopic?tus. Methods The changes at different development stages of mosquitoes(egg,larva,pupae)and gonotrophic cycle were ob?served at different temperature conditions of 10,15,20,25,30,35℃and 40℃. The full developmental cycles were com?pared during different temperatures. Results All the stages of the mosquitoes could not develop at 10℃. Under the different temperatures of 15,20,25,30,35℃and 40℃,the hatchabilities of the mosquitoes were 0,32%,82%,83%,82%and 59%respectively;the pupation rates of the mosquitoes were 38%,53%,84%,88%,72%and 42%respectively;and the emer?gence rates of the mosquitoes were 92% 95% 97% 97% 83%and 17%respectively. The mosquitoes could well develop at 20 25 30℃and 35℃ the development time was 37.73 18.50 16.92 and 13.66 days respectively. Conclusion The devel?opment time of Aedes albopictus is shorter at the higher temperature. The optimum temperature for the mosquitoes to develop is between 25-30℃ and higher or lower the temperatures will suppress the development of the mosquitoes.
3.Bioassay test of Responsar against Anopheles sinensis and Anopheles anthropophagus in lab
Huayun ZHOU ; Julin LI ; Guoding ZHU ; Xiaolin JIN ; Qi GAO
Chinese Journal of Schistosomiasis Control 1989;0(04):-
ObjectiveTo observe the effectiveness of Responsar against Anopheles sinensis and Anopheles anthropophagus. MethodsThe cotton and nylon gauze absorbing Responsar solutions of 10,15 and 20 mg/m~2 (effective dosage) were used in the test. An. sinensis and An. anthropophagus raised in the lab were used as probational worms, having the knockdown power, lethiferous power and effective keeping observation. ResultsWith Responsar of 10,15 and 20 (mg/m~2) impregnating two different kinds of bednets, the KT_(50(s)) of An. sinensis and An. anthropophagus were between 3.98 and 7.30 min after touching the bednets. The knocked down mosquitoes were resumed breeding for 24 h, and the mortality was 100%. Touching nets 3 min, resuming breeding for 24 h, the mortality of mosquitoes was more than 90%. The nets hung for 180 d after impregnated with the insecticide and the knockdown power was still between 8.57 and 16.31 min for Anopheles vector, and resuming breeding for 24 h, the mortality was still 100%. ConclusionThere is strong deadly effect of Responsar to Anopheles sinensis and Anopheles anthropophagus, and the effect can keep more than 180 d.
4.Epidemic and control of malaria in Jiangsu Province
Huayun ZHOU ; Jun CAO ; Weiming WANG ; Julin LI ; Yaping GU ; Guoding ZHU ; Qi GAO
Chinese Journal of Schistosomiasis Control 2009;21(6):503-506
Objective To analyse the epidemic characteristics and control measures of malaria in Jiangsu Province during the past fifty years, evaluate the control effect and explore the current appropriate control strategy and measures. Methods The historical data about malaria cases and control measures from 1951 to 2008 in Jiangsu Province were collected, and the effects of malaria control in different stages were assessed. Results The integrated control measures with emphasis on the control of infectious source were adopted during the stage of two outbreaks of malaria. In the stage of basical elimination of malaria, the comprehensive measures with emphasis on the vector control in the areas of Anopheles anthropophagus were adopted, and the measures with emphasis on the surveillance of infectious source surveillance and early treatment of malaria in other areas were adopted. In the stage of consolidation, the measures including the surveillance of infectious source and management, surveillance of vector and epidemic situation, management of floating population, etc, were adopted. The malaria incidence dropped from 2 495/10 000 in 1960 to 0.09/10 000 in 2008, and was under 1/10 000 in all the counties of Jiangsu Province during the past 2 years, which demonstrated the various measures were feasible and effective in different stages of malaria. Conclusions Malaria has been controlled effectively in Jiangsu Province, however, the improvement of early diagnosis and norm treatment of malaria cases, the enhancement of health education and promotion, as well as the malaria surveillance and management among floating population, are still necessary for achieving the goal of malaria elimination.
5.Residual effect of Demand CS-impregnated bednets to Anopheles sinensis
Julin LI ; Qi GAO ; Huayun ZHOU ; Jun CAO ; Guoding ZHU ; Weiming WANG ; Yaping GU ; Yaobao LIU
Chinese Journal of Schistosomiasis Control 2010;22(2):185-186
Objective To observe the residual effect of Demand CS - impregnated bednets to Anopheles sinensis.Methods The numbers of adult mosquitoes which were knocked down at every minute after treatment were observed by using the enforced contact method recommended by WHO,and the mortality of mosquitoes tested after 24 h was calculated.Results The Kt_(50) of Demand CS - impregnated bednets with impregnations concentrations of 10,15,20 mg/m~2 to Anopheles sineasis were 21.40,16.20,15.70 min,respectively,and the 24 h mortality was 100%.The Kt_(50) of Responsar SC (12.5 % Beta - cyfluthrin) impregnated bednets with a impregnation concentration of 15 mg/m~2 to Anopheles sinensis was 16.06 min,and the 24 h mortality was 100%,too.Conclusions Both the Demand CS - impregnated bednets and the Responsar SC impregnated bednets can kill Anopheles sinensis.
6.Growth difference of Plasmodium vivax in Anopheles sinensis and An.anthropophagus during the periods of clinic attack and diapause of vivax malaria patients
Guoding ZHU ; Qi GAO ; Huayun ZHOU ; Julin LI ; Xiaolin JIN ; Feng LU ; Hui XIA ; Sattabongkot JETSUMON
Chinese Journal of Schistosomiasis Control 1989;0(04):-
Objective To compare the growth of Plasmodium vivax in Anopheles sinensis(An.s) and Anopheles anthropophagus(An.a) during the periods of malaria clinic attack and diapause. Methods The blood samples of patients during the clinic attack and diapause of vivax malaria patients in the vivax epidemic area in China were collected, feeding the mosquitoes of An.s and An.a by using the artificial membrane feeding system in vivo in the lab, and the mosquitoes were dissected during the day 7-9th and 14th after the infection and the oocysts and sporozoites in the stomach and gland of the mosquitoes were counted, respectively. Results The oocyst positive rate in An.s fed by Plasmodium vivax during the fever stage was lower than that in non-fever stage, the sporozoite positive rate in An.a fed by Plasmodium vivax during the fever stage was lower than that in non-fever stage. The positive mosquito rate with oocyst and sporozoite infected by Plasmodium vivax in the fever stage to An.s and An.a were lower than those in non-fever stage. The infective sporozoite intensity of An.s fed by Plasmodium vivax in the fever stage was lower than that in non-fever stage, but the reverse result was found to An.a. Conclusion There is a significant difference between the periods of malaria clinic attack and diapause of the oocyst and sporozoite infection to An.s and An.a.
7.Establishment of malaria early warning system in Jiangsu Province ⅧMalar-ia vector monitoring in Jiangsu Province
Weiming WANG ; Huayun ZHOU ; Guoding ZHU ; Jianxia TANG ; Yuanyuan CAO ; Julin LI ; Jun CAO
Chinese Journal of Schistosomiasis Control 2017;29(1):28-32,37
Objective To understand the population,density,seasonal fluctuation and nocturnal pattern of malaria vectors in Jiangsu Province,thus to provide evidences for malaria elimination in this province. Methods Seven counties(cities,dis?tricts)were selected as the monitoring sites for malaria vectors in Jiangsu Province from 2013 to 2015. The mosquitoes were cap?tured by human bait trapping in bed nets and mosquito?lured lamp overnight,and the seasonal fluctuation and nocturnal pattern of malaria vectors were observed. Results A total of 11 041 Anopheles sinensis mosquitoes were captured by the mosquito?lured lamps in 7 counties of Jiangsu Province from 2013 to 2015,and no An. anthropophagous was found. Among all the 7 monitoring sites,the number of An. sinensis captured in Sihong County was the most(6 742 mosquitoes),while that in Xuyu County was the least(34 mosquitoes). During this period,the density peaks of An. sinensis were the first half of July,the first half of August and the second half of July. A total of 2 421 An. sinensis were collected in 7 monitoring sites from 2013 to 2015 by human bait trapping in bed nets overnight. Among all the 7 monitoring sites,the captured number of An. sinensis in Sihong County was the most(1 085 mosquitoes),while that in Ganyu County was the least(13 mosquitoes). The nocturnal peak of An. sinensis was from 19:00 to 20:00 and 525 An. sinensis mosquitoes were captured during this period of time,which accounted for 21.68%of the total. Hereafter,the captured number of An. sinensis reduced over time. Conclusion The density of An. sinensis mosquitoes is still high in individual areas in Jiangsu Province,so the epidemic and vector monitoring still should be strengthened to prevent the local transmission of imported malaria.
8.Analysis of the Sequences of the Ribosomal DNA ITS_2 Region for Differenciating Anopheline Mosquitoes within Hyrcanus Group
Qi GAO ; Huayun ZHOU ; Julin LI ; Fenghua LI ; Tonggyu CHOE ; Sungchan YOM ; Guoding ZHU ; Jun CAO ;
Chinese Journal of Parasitology and Parasitic Diseases 1997;0(05):-
Objective To analyze the genetic characteristics of ribosomal DNA ITS 2 region for differenciating anopheline mosquitoes within Hyrcanus group. Methods The ribosomal DNA ITS 2 region of both laboratory line and filed collected An. anthropophagus and An. sinensis as well as the field collected An. yatsushiroensis and An. lester i were amplified and sequenced. The sequencing data were then analyzed for the restriction mapping using Omega Sequencing analysis program. Results and Conclusion The length of the sequences of An. sinensis, An. anthropophagus, An. yatsushiroensis and An. lesteri are 472, 452, 456 and 456 bp respectively. The restriction mapping showed that there were different restriction digesting sites among the ribosomal DNA ITS2 region sequences from An. sinensis, An. anthropophagus, An. yatsushiroensis and An. lesteri . On the basis of the sequence differences among the anopheline species within Hyrcanus group, it is possible to develop new technique for genetic identification of anopheline mosquitoes.
9.Analysis of channels of going abroad of imported malaria patients in Jiang-su Province,China
Yuanyuan CAO ; Huayun ZHOU ; Guoding ZHU ; Weiming WANG ; Yaobao LIU ; Jun CAO
Chinese Journal of Schistosomiasis Control 2016;28(6):653-656
Objective To analyze the channels of going abroad of imported malaria patients in Jiangsu Province,so as to provide the evidence for the control of imported malaria and health intervention for high?risk population. Methods The data of imported malaria cases in Jiangsu Province in 2015 were collected and the channels of going abroad were analyzed. The Quan?tum GIS 1.7.4 software was applied to map. Results Totally 405 imported cases were reported in Jiangsu Province in 2015, and the cases increased by 14.1%compared with those in 2014. All the patients were migrant workers. The migrant workers were mostly sent abroad by construction companies[43.21%(175/405)]. The dispatching companies were mainly concentrated in Taizhou,Lianyungang,Zhenjiang and Yangzhou cities,accounting for 6.17%(25/405),3.21%(13/405),2.72%(11/405) and 2.22%(9/405),respectively. Totally 176(43.46%)patients returned to China having accompanied workers,and 1.21%(9/745)of accompanied workers were found having symptoms of malaria later. Conclusions It is difficult to monitor malaria in overseas migrant works in Jiangsu Province. The channels of going abroad of migrant workers are various and complicated ,for?mulating the main difficulty and challenge of imported malaria control.
10.Susceptibility of Anopheles anthropophagus from different areas of China to Plasmodium vivax
Huayun ZHOU ; Guoding ZHU ; Julin LI ; Xiaolin JIN ; Feng LU ; Yaobao LIU ; Sattabongkot JETSUMON ; Qi GAO
Chinese Journal of Schistosomiasis Control 1989;0(04):-
Objective To compare the susceptibility of Anopheles anthropophagus from Jiangsu, Guangdong and Liaoning provinces in China to Plasmodium vivax.Methods The blood samples of patients with P. vivax in endemic areas of China were collected to feed the mosquitoes of An. anthropophagus from different areas by using the artificial in vitro membrane feeding system in the lab, and then the mosquitoes were dissected during the 7-9th day and on the 14th day after the feeding and the oocysts and sporozoites in the stomach and salivy gland of mosquitoes were counted. Results The mosquitoes from Jiangsu, Guangdong and Liaoning were simultaneously fed with the blood of 35 cases of P. vivax. The oocyst positive rates of An. anthropophagus from Jiangsu, Guangdong and Liaoning during the 7-9th day after the feeding were 68.57%, 60.00% and 68.57%, as well as the sporozoite positive rates of them on the 14th day after the feeding were 22.86%, 14.29% and 22.86%, respectively. On the 7th day after the feeding, 228, 235, 228 mosquitoes of An. anthropophagus from Jiangsu, Guangdong and Liaoning were dissected, and the positive mosquito rates with oocyst infection were 28.07%, 25.11% and 26.75%, respectively. On the 14th day after the feeding, 150, 142, 135 mosquitoes of An. anthropophagus from the three areas were dissected, the positive rates with sporozoite infection were 10.67%, 8.45% and 11.85%, respectively. The num-bers of mosquitoes dissected with infective grade("+","++","+++","++++") of sporozoites of An. anthropophagus from Jiangsu, Guangdong and Liaoning were 4, 3, 2, 7; 2, 2, 3, 7 and 1, 6, 3, 8, respectively. Conclusions An. anthropophagus from Jiangsu, Guangdong and Liaoning is susceptible to the parasites of Plasmodium vivax and there is no significant difference among the susceptibilities of An. anthropophagus from the three areas to Plasmodium vivax.