2.1 Study sites and target population
The study was carried out in Anyi County, Jiangxi Province, where schistosomiasis transmission has been interrupted more than 20 years [8]. Two villages and primary schools (Laoxia and Xubu) were selected as the experimental group and the control group, respectively. Adult villagers aged 16-60 and pupils aged 8-10 were designated as the target population for the study.
The study villages and schools were 7 kilometers apart and similar with their natural environment, social-economic status, culture, people’s livelihood, agricultural patterns (mainly planting rice), and school class settings. The two villages reached the criteria of schistosomiasis transmission interruption, (i.e. no intermediate host snails and schistosomiasis case were found in 5 years) in 1987. However, schistosome-infected snails and acute schistosomiasis cases in pupils reappeared in 1997, 2004 and 2010 in these two villages.
In April 2015, snail surveys by environmental sampling method[14] were conducted by researchers within an area of 21,989 m2 of 19 environmental sites in the experimental village and an area of 19,536 m2 of 15 sites in the control village, respectively. No snail was found in both villages.
In October 2015, a total of 243 people (113 adults and 130 pupils) in the experimental village and 226 people (107 adults and 119 pupils) in the control village were subjected to stool examination by the Kato-Katz technique[15] for diagnosis of S. japonicum infection. There was no case with schistosomiasis found in both villages.
2.2 Baseline survey
Before intervention, a baseline survey was carried out, both in the experimental village and the control village including their schools in 2015. A questionnaire about the knowledge, attitude, belief, and practice (KABP) with regard to schistosomiasis control was conducted in all study groups.
To obtain information for sample size calculations, a pre-survey was conducted in a nearby village for measuring the rates of awareness of knowledge, correct attitude, and belief-owning about schistosomiasis control in adult villagers and pupils. With α=0.05 and a power of 80%, we calculated the minimum sample size for each group by the formula for two sample rate test, i.e. N={Zα/2[πc(1-πc)(Q1-1+Q2-1 )]0.5 + Zβ[π1Q1-1(1-π1)+π2Q2-1(1-π2)]0.5}2/(π1-π2)2. We needed at least 26 adult villagers and 25 pupils per village. Considering a drop-out rate of 10% and respecting villagers’ will to join the study, 120 adults and 140 pupils each village were enrolled for participation in the study.
Before the onset of the study, researchers had informed the study populations about the aim, content and methods of the study, and the informed consents were signed by adult villagers and pupils’ legal guardian in all study groups. All people in study groups voluntarily joined this study with informed consents.
2.2.1 Predisposing factors survey for schistosomiasis control
A uniform questionnaire was designed and printed. The predisposing factors including knowledge , belief and attitude towards schistosomiasis were investigated in study groups.
2.2.1.1 Knowledge about schistosomiasis control
There were a total of 10 questions of knowledge about schistosomiasis, including the hazard to human health and livestock due to schistosomiasis, the presented symptoms of human advanced schistosomiasis, susceptible population and livestock, morphological identification of snail, the role of snails in schistosomiasis transmission, local snail habitats, suitable month for snail surveys, and the main measures to eliminate schistosomiasis. A total score of 60 or above (maximum possible score: 100) indicated that respondents had sufficient knowledge of schistosomiasis control. After the interview, the number of individuals who passed or did not pass and the awareness rate was recorded.
2.2.1.2 Attitude towards schistosomiasis control
The attitude of pupils to talk to their family members and others about schistosomiasis was recorded, as well as the attitude of adult villagers to participate and conduct snail surveys was recorded. The respondent who has willingness to disseminate knowledge and participate in the snail survey actively was judged as having positive attitudes towards schistosomiasis control. The number and rate of respondents with positive attitudes was also recorded.
2.2.1.3 Belief of schistosomiasis control
Asking the target population whether believe that schistosomiasis can be eliminated or not was also investigated. The respondents who believed that schistosomiasis can be eliminated were counted as the believer. The number and rate of believers were recorded.
2.2.2 Compliance towards schistosomiasis control
2.2.2.1 Compliance towards disseminating knowledge of schistosomiasis control in pupils
At the end of each month from March to June and September to October 2015, pupils were interviewed by investigators to understand the frequency of disseminating knowledge of schistosomiasis control conducted by pupils to their family members and others was recorded. The number of students who disseminated the knowledge was recorded. The compliance was defined as the percentage of students who fitted this description.
2.2.2.2 Compliance towards snail survey in adult villagers
From April to October 2015 the frequency of active snail surveys conducted by adult villagers was recorded at the end of each month, and the compliance was calculated as the percentage of adult villagers who fitted this description. A training class course on snail survey was held for the adult villagers before they conducted the survey, which consisted of exhibition of intermediate host snail samples, explaining the size, morphology of snails and snail habitats, and demonstrating and teaching how to collect snails.
2.3 Intervention of schistosomiasis health education and health promotion
After the baseline survey, a model of intervention of health education and promotion, namely, “information communication + behavior participation + behavior encouragement”, was implemented in the experimental village from March to October, 2016.
2.3.1 Information communication
For pupils, a 40-minute course of health education was taught each week by school teachers and professional for schistosomiasis control , and there were a total of 4 courses during the intervention. The courses consisted of a video-tape explaining the harmful effects of schistosomiasis, explaining snail morphology, snail habitats, the role of snail in the transmission of schistosomiasis and consequences of reoccurred snails in transmission-interrupted areas with schistosomiasis, and exhibition of samples such as adult schistosomes and intermediate host. A closed book exam was held to assess the effect of teaching.
For adult villagers, information communication consisted of the following parts: (i) a similar course as for pupils was provided, including exhibits of the parasite and its intermediate host snail and a video explaining the harmful effects of the disease. (ii) health education materials regarding schistosomiasis control such as pictures, brochures, leaflets, and a bulletin board were provided to villagers. (iii) a song with regard to schistosomiasis was taught and warning signs were put up near all suspicious snail habitats to remind villagers to conduct snail surveys actively.
2.3.2 Behavior participation
For pupils, four kinds of activities were organized, i.e. conducting a knowledge contest on schistosomiasis control, receiving a presentation by cured schistosomiasis patients, participating in a mock snail survey on site and writing an essay about schistosomiasis control.
For adult villagers, two activities, namely, receiving a lecture by cured schistosomiasis patients and participating in a mock snail survey on site, were organized. For guaranteeing villagers to attend the lecture and join the snail survey, reverenced village heads in the study villages were mobilized to organize these activities. A souvenir, such as a towel, soap, pencil, or school bag, was given to participants after every activity was finished.
Before the mock snail survey, a training course for villagers and pupils was held to explain the snail morphology, exhibit snail samples, demonstrating the survey method and safety measures. After the survey, a reward, a towel or a pencil box, was awarded to those who found the snail samples, which were randomly bestrewed in the environments suitable for snail living by researchers on purpose.
2.3.3 Behavior encouragement
For pupils, the most outstanding class and individual with regard to schistosomiasis control were appraised and elected. A system of dissemination of schistosomiasis knowledge was formulated, in which each student was required to disseminate the knowledge of schistosomiasis to their family or others at least once per week. In addition, honor and reward was given to those who conducted propaganda actively.
For adult villagers, a reward system was established. i.e. honor and reward was given to those who participated in the snail survey actively, especially who can find and report snails.
2.4 Assessment of intervention effect
The effect of interventions was assessed both in the experimental and the control groups. The assessment content, methods and standards were used in the same way during the baseline method.
2.5 Quality control
2.5.1 Personal training
To minimize potential biases, all workers who participated in this study were well trained by researcher and they adhered to uniformed contents, methods and standards before and after the interventions.
2.5.2 Inspection and check
The progress and quality of this study were monitored and inspected by the principal investigator who checked the data and regularly visited the field sites to verify the authenticity of the data.
2.6 Statistical analysis
All data were put into a computer. A database was established with Epi Data 2.0 software, and the statistical analysis was conducted by SAS 8.2 software. The χ2-test was used to compare proportions before and after the implementation of health education and health promotion, with significant levels setting as 0.05.