1.Climbing-upward Inhibition of Oncomelania hupensis by Niclosamide Combination
Dan ZHU ; Faxian XIE ; Ziping BAO ; Dabei ZHU ; Chuanhua NI ;
Chinese Journal of Parasitology and Parasitic Diseases 1997;0(06):-
Objective To develop a combination of molluscicide/insecticide with a good molluscicidal effect, especially an inhibitory effect on climbing upward of Oncomelania hupensis . Methods Experiments on molluscicidal and snail climbing inhibition effect of the combination of niclosamide and shachongding [(dimethylamine) trithacyclohexane hydrochloride] were conducted by immersion and spraying in laboratory. Results The combination of niclosamide (0.2 mg/L) and shachongding (0.1 mg/L) showed an inhibition of 92.67% of snails to climb up. There was no significant difference in molluscicidal effect between the combination (LC 90 0.198 mg/L) and niclosamide alone (LC 90 0.207 mg/L). Conclusion The combination showed an effective inhibition on the climbing upward of snails in water so as to improve the molluscicidal effect and reduce the cost of mollusciciding.
2.Schistosomiasis control effect of measures of replacing cattle with machine for cultivation and forbidding depasturage of livestock on marshlands in marshland and lake regions
Chunli CAO ; Ziping BAO ; Pengcheng YANG ; Zhao CHEN ; Jun YAN ; Guanghui REN ; Yiyi LI ; Shunxiang CAI ; Jianbing LIU ; Jing XU ; Shizhu LI ; Jiagang GUO ; Xiaonong ZHOU
Chinese Journal of Schistosomiasis Control 2014;(6):602-607
Objective To evaluate the schistosomiasis control effect of the measures of replacing cattle with machine for cul?tivation and forbidding depasturage of livestock on marshlands in marshland and lake regions. Methods The retrospective re?view and field survey were implemented in the Jiangling and Gongan counties of Hubei Province where were implemented with the measure of replacing cattle with machine for cultivation,and Yuanjiang and Huarong counties of Hunan Province where were implemented with the measure of forbidding the depasturage of livestock on marshlands. The schistosome infection status of hu?man,cattle,and Oncomelania hupensis snails,and schistosome?infested field excreta were surveyed from 2007 to 2013. The ef?fects of the interventions were compared before and after their implementations. Results The 6 villages of Hubei Province were implemented with the measure of replacing cattle with machine for cultivation,and 7 villages of Hunan Province were imple? mented with the measure of forbidding the depasturage of livestock on marshlands. From 2007 to 2013,the schistosome infection rates of residents declined from 3.95%to 0.70%(χ2 =128.376,P<0.05),with the descend range of 82.53%. The descend ranges of the measures of replacing cattle with machine for cultivation and forbidding the depasturage of livestock on marshlands were 83.081%and 81.62%respectively,and there was no significant difference between the two measures(χ2 =0.132,P>0.05). The infection rate of cattle decreased from 3.66%in 2007 to 0.65%in 2013,and the descend range was 82.24%(χ2=13.692,P<0.05). The field excreta was surveyed in the snail breeding place in 2013. The investigated area was 157.435 hm2, and 625 samples of field feces of cattle were collected with the density of field excreta of 3.97/hm2,and the positive rate was 1.12%(7/625). The schistosome infection rate of snails and the density of infected snails decreased successively from 2007, and no infected snails were detected from 2011 to 2013. Conclusions The schistosomiasis endemic situation are decreased sig?nificantly after the interventions of replacing cattle with machine for cultivation and forbidding the depasturage of livestock on marshlands. Therefore,schistosomiasis control effect of these measures is notable in the marshland and lake regions.
3.Investigation on compliance of forbidden depasturing livestock on marshland with Oncomelania snails in schistosomiasis endemic areas
Chunli CAO ; Jing WANG ; Ziping BAO ; Hongqing ZHU ; Shunxiang CAI ; Yiyi LI ; Dong LI ; Jiachang HE ; Leping SUN ; Xianhong MENG ; Bo ZHONG ; Xiguang FENG ; Zhengming SU ; Jun LI ; Xiaonan GU ; Hao WANG ; Weiwei RU ; Weisheng JIANG ; Shizhu LI ; Qiang WANG ; Xiaonong ZHOU ; Jiagang GUO ; Gengming ZHAO
Chinese Journal of Schistosomiasis Control 2009;21(6):482-485
Objective To study the compliance of forbidden depasturing livestock on the marshland with Oncomelania snails in schistosomiasis endemic areas. Methods According to 3 levels of human infection rates as > 10% ,5%-10% and <5% , 2 204 residents selected randomly from the schistosomiasis endemic villages were sampled with the stratified cluster sampling method in Hunan, Hubei, Jiangxi, Anhui, Jiangsu, Sichuan and Yunnan provinces, and investigated by questionnaire. The contents of the questionnaire included the recognition and implementation of forbidden depasturing livestock on marshland with Oncomelania snails and breeding livestock in bam. Results A total of 78.4% residents agreed forbidden depasturing livestock on marshland with snails, but 3. 7% residents disagreed it. A total of 83. 9% residents considered the relationship between breeding livestock in bam and schistosomiasis control, but 3. 1% residents thought that it was no relationship. The main reasons of depasturing livestock on marshland with Oncomelania snails were the high cost of breeding livestock in bam (36. 2% ) , unaccustomed (26.4% ) and no room for breeding livestock in bam (25.4% ). Conclusion Forbidden depasturing livestock on the marshland with Oncomelania snails should be strengthened according to the local economic, nature environment, agriculture, residents'culture degree and agriculture habit.
4.Expert consensus on recombinant B subunit/inactivated whole-cell cholera vaccine in preventing infectious diarrhea of enterotoxigenic Escherichia coli
Chai JI ; Yu HU ; Mingyan LI ; Yan LIU ; Yuyang XU ; Hua YU ; Jianyong SHEN ; Jingan LOU ; Wei ZHOU ; Jie HU ; Zhiying YIN ; Jingjiao WEI ; Junfen LIN ; Zhenyu SHEN ; Ziping MIAO ; Baodong LI ; Jiabing WU ; Xiaoyuan LI ; Hongmei XU ; Jianming OU ; Qi LI ; Jun XIANG ; Chen DONG ; Haihua YI ; Changjun BAO ; Shicheng GUO ; Shaohong YAN ; Lili LIU ; Zengqiang KOU ; Shaoying CHANG ; Shaobai ZHANG ; Xiang GUO ; Xiaoping ZHU ; Ying ZHANG ; Bangmao WANG ; Shuguang CAO ; Peisheng WANG ; Zhixian ZHAO ; Da WANG ; Enfu CHEN
Chinese Journal of Clinical Infectious Diseases 2023;16(6):420-426
Enterotoxigenic Escherichia coli(ETEC)infection can induce watery diarrhea,leading to dehydration,electrolyte disturbance,and even death in severe cases. Recombinant B subunit/inactivated whole-cell cholera(rBS/WC)vaccine is effective in preventing ETEC infectious diarrhea. On the basis of the latest evidence on etiology and epidemiology of ETEC,as well as the effectiveness,safety,and health economics of rBS/WC vaccine,National Clinical Research Center for Child Health(The Children’s Hospital,Zhejiang University School of Medicine)and Zhejiang Provincial Center for Disease Control and Prevention invited experts to develop expert consensus on rBS/WC vaccine in prevention of ETEC infectious diarrhea. It aims to provide the clinicians and vaccination professionals with guidelines on using rBS/WC vaccine to reduce the incidence of ETEC infectious diarrhea.
5.Molluscicidal effect of spraying 5% niclosamide ethanolamine salt granules with drones against Oncomelania hupensis in marshland areas
Chunli CAO ; Jianfeng ZHANG ; Yefang LI ; Xuehui SHEN ; Junyi HE ; Ziping BAO ; Suying GUO ; Kun YANG ; Jing XU ; Shizhu LI ; Xiaonong ZHOU
Chinese Journal of Schistosomiasis Control 2024;36(5):531-534
Objective To evaluate the molluscicidal effect of spraying 5% niclosamide ethanolamine salt granules with drones against of Oncomelania hupensis snails in snail habitats in marshland areas. Methods From September to October, 2022, marshlands were sampled from Dantu District, Zhenjiang City, Jiangsu Province as study areas, and assigned into four groups, of approximately 3 000 m2 per group. In Group A, environmental cleaning was performed, followed by spraying 5% niclosamide ethanolamine salt granules with knapsack sprayers at a dose of 40 g/m2, and in Group B, 5% niclosamide ethanolamine salt granules were sprayed with knapsack sprayers at a dose of 40 g/m2 without environmental cleaning, while in Group C, environmental cleaning was conducted, followed by spraying 5% niclosamide ethanolamine salt granules with drones at a dose of 40 g/m2, and in Group D, 5% niclosamide ethanolamine salt granules were sprayed with drones at a dose of 40 g/m2 without environmental cleaning. Then, the study areas in each group were equally divided into six blocks, with Block 1 for baseline surveys and blocks 2 to 6 for snail surveys 1, 3, 5, 7, 14 days following chemical treatment. The mortality of snails and the reduction of the density of living snails were calculated. Results A total of 132 frames were surveyed during the period from September to October 2022, and the occurrence of frames with living snails and means density of living snails were 61.36% (81/132) and 1.58 snails/0.1 m2, respectively. The overall mortality rates of snails were 43.02% (77/179), 38.69% (77/199), 47.78% (86/180) and 31.02% (58/187) 14 days following chemical treatment in groups A, B, C and D, respectively (χ2 = 11.646, P < 0.05), and there were differences detected in the snail mortality between group A and D, and between groups C and D (both Padjusted values < 0.05). The adjusted mortality rates of snails were 37.42%, 36.07%, 38.85% and 40.40% in groups A, B, C and D 14 days post-treatment, and the density of living snails decreased by 48.10%, 63.29%, 67.09% and 69.62% 14 days post-treatment relative to pre-treatment, respectively. Conclusions Chemical treatment with drones is feasible for O. hupensis snail control in marshland areas; however, the molluscicidal effect of spraying 5% niclosamide ethanolamine salt granules with drones is comparable to spraying chemicals manually in marshland areas regardless of environmental cleaning.
6.Molluscicidal effect of spraying different formulations of niclosamide ethanolamine salt with drones against Oncomelania hupensis in ditches
Zelin ZHU ; Xia ZHANG ; Junyi HE ; Ying CHEN ; Weisi WANG ; Hehua HU ; Chunli CAO ; Ziping BAO ; Suying GUO ; Liping DUAN ; Yi YUAN ; Jing XU ; Shizhu LI ; Xiaonong ZHOU
Chinese Journal of Schistosomiasis Control 2024;36(5):527-530
Objective To evaluate the molluscicidal effect of spraying different formulations of niclosamide ethanolamine salt with drones against Oncomelania hupensis in ditches. Methods A semi-dry and semi-wet ditch with O. hupensis snails was selected in the second branch field of Jiangbei Farm, Jiangling County, Hubei Province in May 2023, and divided into 4 experimental areas, named groups A1, A2, B1 and B2. Environmental cleaning was performed in groups A1 and B2, and was not conducted in groups A2 or B2. Then, 50% wettable powder of niclosamide ethanolamine salt was sprayed with drones at an effective dose of 2 g/m2 in groups A1 and A2, and 5% niclosamide ethanolamine salt granule was sprayed with drones at an effective dose of 2 g/m2 in groups B1 and B2. O. hupensis snails were surveyed using the systematic sampling method 1, 3, 5, 7, 14 days after spraying, and the natural mortality and corrected mortality of O. hupensis snails were calculated. Results The occurrence of frames with living snails, mean density of living snails and natural mortality of snails were 97.50% (117/120), 6.30 snails/0.1 m2 and 1.18% (9/765) in the test ditch before spraying, respectively. There were significant differences in the mortality of snails among four groups 1, 3, 5, 7 and 14 days after spraying niclosamide formulations with drones (χ2 = 17.230, 51.707, 65.184, 204.050 and 34.435, all P values < 0.01). The overall mortality rates of snails were 94.51% (1 051/1 112), 79.44% (908/1 143), 96.54% (977/1 012) and 88.55% (1 021/1 153) in groups A1, A2, B1 and B2 (χ2 = 207.773, P < 0.05), respectively. In addition, there was no significant difference in the overall snail mortality between groups A1 and B1 (P > 0.05), and the snail mortality in groups A1 and B1 were both statistically different from that in groups A2 and B2 (all P values < 0.05). Conclusion Both 50% wettlable powder of niclosamide ethanolamine salt and 5% niclosamide ethanolamine salt granule sprayed with drones are active against O. hupensis snails in ditches, and environmental cleaning may improve the molluscicidal effect.