[Effects and cost of four formulations of niclosamide ethanolamine salt in snail control in field].

Objective: To investigate the effects and cost of four formulations of niclosamide ethanolamine salt in snail control in the field in marshland and lake regions, so as to provide the evidence for drawing up the plan of molluscicide using in schistosomiasis endemic areas.

Methods: One drainage channel and one channel without water in the same area with snails in Jiangling County, Jingzhou City were selected as the research fields. The drainage channel was divided into 9 sections, except one section as a blank control group where the natural death rate of snails was observed only, and the remaining 8 sections were taken as the observation groups, where different dosages of 4% niclosamide ethanolamine salt powder, 5% niclosamide ethanolamine salt granules, 25% niclosamide ethanolamine salt suspending agent, 26% metaldehyde and niclosamide ethanolamine salt suspending agent, and 50% niclosamide ethanolamine salt wettable powder were used respectively.

[Development and application of Jingcen DY-1 spraying tanker for Oncomelania hupensis snail control].

Objective: To develop a Jingcen DY-1 type spraying tanker for Oncomelania hupensis snail control and evaluate its effect of field application as well as the cost.

Methods: The currently available tractor was used as a vector, and the mechanical and electrical equipments and containers were integrated with shafts, pipelines and electric lines to produce a spraying tanker for snail control, with the functions of carrying people and molluscicides, generating electric power and getting water, mixing stocking solutions, adjusting molluscicide solutions evenly, and spraying drugs. The volume of the molluscicide solution, flow rate of water injection, and the flow rate, range and advance speed of the spray gun were tested, and the solution concentrations of molluscicide in the tanker and at the muzzle of the spray gun at different time were detected.

[ snail control effects of molluscicides with different formulations in field in marshland and lake regions].

Objective: To observe the snail control effects of molluscicides with different formulations in the ditch with unstable water level in field of marshland and lake areas, so as to provide the evidence for formulating the prevention strategies.

Methods: A drainage channel with snails in Jiangling County, Jingzhou City were selected as the study field, then it was divided into 6 segments, except 1 segment was treated as the blank control group for observing the natural mortality rate of the snails, the other 5 segments were treated as observation groups, where 4% niclosamide ethanolamine salt powder, 5% niclosamide ethanolamine salt granule, 25% suspension concentrate of niclosamide ethanolamine salt, 26% suspension concentrate of metaldehyde and niclosamide ethanolamine salt, 50% niclosamide ethanolamine salt wettable powder were applied respectively. Before and after the mollusciciding, the snail surveys were carried out through the systematic sampling method, and the short- and long-term effects of snail control were observed, and the mortality rates of the snails on the slope above the water level and those below the water level were compared.

[Analysis of endemic situation of schistosomiasis in Jingzhou City from 2004 to 2014].

Objective: To analyze the change of endemic situation of schistosomiasis in Jingzhou City of Hubei Province, so as to provide evidence for the development of future control strategy.

Methods: The data of endemic situation of schistosomiasis and the implementation of integrated control measures were collected and analyzed in the 9 counties (districts, cities) of Jing-zhou City from 2004 to 2014.

Results: The endemic situation of schistosomiasis appeared a decline year by year since 2004.

[Assessment of risk factors of schistosomiasis transmission control in Jingzhou City].

Objective: To understand the key risk factors of schistosomiasis transmission in Jingzhou City, so as to provide the evidence for improving the treatment of these risk factors.

Methods: Each village of six counties was investigated and 3 environments were surveyed each village for the distribution of Oncomelania snails and animal stools in the field. The results were analyzed and the risk factors of schistosomiasis transmission were assessed.

[Classification and grading of environments with Oncomelania hupensis snails inside embankment of marshland and lake areas].

Objective: To classify and grade the environments with Oncomelania hupensis snails inside embankment in marshland and lake areas, so as to improve the work efficiency and realize the systematic management.

Methods: The schistosomiasis endemic area Liaodi and Xiongdi villages in Jiangling County, Hubei Province were selected as the experiment villages, and the environments with snails in the two villages were divided into sections with a length of 500 m, then the snail situation were surveyed by the systematic sampling method with 10 m and 50 m a frame respectively. The environments were classified according to the discovery of infected snails and wild fecal contamination, and the numbers of sites with snails and their areas in different classes were recorded.

[Molluscicidal effect of 10% LDS in fields].

Objective: To evaluate the molluscicidal effects of 10% salt of quinoid-2', 5-dichloro-4'-nitrosalicylanilide (LDS) on Oncomelania hupensis in the fields, so as to provide the evidence for the application of LDS in the fields.

Methods: The fields where O. hupensis density was relative high were selected as the experimental area and the different concentrations of LDS were used for molluscicidal effects with the immersion, insufflation and powdering methods, and 50% wettable powder of niclosamide ethanolamine salt (WPN) was used as the control.

[Relationship of schistosome infection with environment and behavioral characteristics of residents in Jingzhou area].

Objective: To understand the relationship of schistosome infection with environment and the behavioral characteristics of residents in Jingzhou area.

Methods: The schistosomiasis patients (positive in stool examinations) were investigated with the questionnaire at home. The content of questionnaire included the hygienic and environmental situation, the behavioral characteristics of the residents, and the treatment of schistosomiasis patients.

[Environmental distribution and disposal measures of infected Oncomelania snails in Jingzhou City].

A survey of Oncomelania snail distribution was carried out with the systematic sampling method in combination with the environmental sampling method. A questionnaire survey was performed to find out the sites where stool examination-positive patients were infected. The results showed that there were 1 721 infected snail spots in Jingzhou City.

[Effect of modified crushing-cercariae escaping method on detection of infected Oncomelania snails in field].

Objective: To evaluate the effect of a modified crushing-cercariae escaping method on the detection of infected Oncomelania snails in the field.

Methods: A snail survey was carried out in Jingzhou City in the spring of 2011, and the villages were randomly divided into several groups, the coincidence rates, detection rates and the labour cost of the modified crushing-cercariae escaping method and crushing method were compared.

Results: A total of 14 snail spots were surveyed, and the coincidence rate of the two methods was 100%.

[Schistosomiasis control effect of county promotion and comprehensive control interventions in lake and marshland regions].

Objective: To evaluate the schistosomiasis control effect of county promotion and comprehensive control interventions in Jingzhou City.

Methods: The data of schistosomiasis endemic situation of 9 counties (cities, districts) in Jingzhou City from 2006 to 2010 were collected by a retrospective survey method, and the schistosome infection situation of residents and cattle were selectively examined in November, 2010.

Results: The endemic situation in Jingzhou City from 2006 to 2010 presented a decline tendency.

[Survey of causes of infected Oncomelania snails and infectious sources of schistosomiasis in marshland and lake region of Jingzhou City].

Objective: To explore the causes of infected Oncomelania snails and the sources of infection of schistosomiasis in marshland and lake regions of Jingzhou City, so as to provide the evidence for the establishment of control strategy.

Methods: The snail environments in villages with or without cattle in Gong'an and Jianli counties, Hubei Province were selected, the snail status, infection status of people and livestock and wildlife reservoir host (mice), as well as the contamination status of wild faeces were surveyed, and the infectivity of water in investigated villages without cattle were detected by sentinel mice. The correlation between the densities of infected snails and positive faeces were tested by the rank correlation method.

[Comparative evaluation of models for infectious source control of schistosomiasis in lake and marshland regions].

Objective: To compare the effect of different models for the control of infectious source of schistosomiasis, so as to explore the control models suitable for lake and marshland regions.

Methods: The models of "replacement of cattle with machine" and "grazing prohibition and establishing fixed pasture" were implemented in 2 towns of Gong'an and Jianli counties, Hubei Province, respectively, and the data of infection situation of human and livestock, Oncomelania hupensis snail situation and the contamination status of wild faeces were collected and analyzed from 2008 to 2010.

Results: In 2010, for the model of "replacement of cattle with machine", the infection rate of residents in the observation group decreased by 56.