Sharing the WHO guideline on control and elimination of human schistosomiasis to achieve the goal of schistosomiasis elimination in China / 中国血吸虫病防治杂志

Currently, the national schistosomiasis control program of China is moving from transmission interruption to elimination, and there are multiple challenges during the stage moving towards the progression of schistosomiasis elimination, including a high difficulty in shrinking snail-infested areas, unstable achievements for infectious source control, imperfect surveillance system and a reduction in schistosomiasis control and administration. Based on the core suggestions proposed in the 2022 WHO guideline on control and elimination of human schistosomiasis, recommendations on schistosomiasis surveillance system building, development of novel diagnostics, adjustment of the schistosomiasis control strategy and maintaining and improvements of the schistosomiasis control capability are proposed for the national schistosomiasis control program of China in the new era according to the actual status of schistosomiasis control in China. Formulation of the national schistosomiasis control strategy and goal from One Health perspective, verification of transmission interruption and elimination of schistosomiasis, precision implementation of schistosomiasis control interventions with adaptations to local circumstances, development and application of highly sensitive and specific diagnostics are recommended for elimination of schistosomiasis in China. In addition, the implementation of the 2022 WHO guideline on control and elimination of human schistosomiasis may guide the elimination of schistosomiasis in China.

Contribution to global implementation of WHO guideline on control and elimination of human schistosomiasis by learning successful experiences from the national schistosomiasis control program in China / 中国血吸虫病防治杂志

Schistosomiasis is a parasitic disease that seriously hinders socioeconomic developments and threatens public health security. To achieve the global elimination of schistosomiasis as a public health problem by 2030, WHO released the guideline on control and elimination of human schistosomiasis on February, 2022, with aims to provide evidence-based recommendations for schistosomiasis morbidity control, elimination of schistosomiasis as a public health problem, and ultimate interruption of schistosomiasis transmission in disease-endemic countries. Following concerted efforts for decades, great achievements have been obtained for schistosomiasis control in China where the disease was historically highly prevalent, and the country is moving towards schistosomiasis elimination. This article reviews the successful experiences from the national schistosmiasis control program in China, and summarizes their contributions to the formulation and implementation of the WHO guideline on control and elimination of human schistosomiasis. With the progress of the "Belt and Road" initiative, the world is looking forward to more China's solutions on schistosomiasis control.

Decoding the evolution of preventive chemotherapy schemes for schistosomiasis in China to improve the precise implementation of the WHO guideline on control and elimination of human schistosomiasis / 中国血吸虫病防治杂志

Preventive chemotherapy is one of the pivotal interventions for the control and elimination of schistosomiasis, which is effective to reduce the morbidity and prevalence of schistosomiasis. In order to promote the United Nations' sustainable development goals and the targets set for schistosomiasis control in the Ending the neglect to attain the Sustainable Development Goals: a road map for neglected tropical diseases 2021-2030, WHO released the guideline on control and elimination of human schistosomiasis in 2022, with major evidence-based updates of the current preventive chemotherapy strategy for schistosomiasis. In China where great success has been achieved in schistosomiasis control, the preventive chemotherapy strategy for schistosomiasis has been updated several times during the past seven decades. This article reviews the evolution of the WHO guidelines on preventive chemotherapy and Chinese national preventive chemotherapy schemes, compares the current Chinese national preventive chemotherapy scheme and the recommendations for preventive chemotherapy proposed in the 2022 WHO guideline on control and elimination of human schistosomiasis, and proposes recommendations for preventive chemotherapy during the future implementation of the 2022 WHO guideline, so as to provide insights into schistosomiasis control among public health professionals engaging in healthcare foreign aid.

Analysis of the new WHO guideline to accelerate the progress towards elimination of schistosomiasis in China / 中国血吸虫病防治杂志

On February 2022, WHO released the evidence-based guideline on control and elimination of human schistosomiasis, with aims to guide the elimination of schistosomiasis as a public health problem in disease-endemic countries by 2030 and promote the interruption of schistosomiasis transmission across the world. Based on the One Health concept, six evidence-based recommendations were proposed in this guideline. This article aims to analyze the feasibility of key aspects of this guideline in Chinese national schistosomiasis control program and illustrate the significance to guide the future actions for Chinese national schistosomiasis control program. Currently, the One Health concept has been embodied in the Chinese national schistosomiasis control program. Based on this new WHO guideline, the following recommendations are proposed for the national schistosomiasis control program of China: (1) improving the systematic framework building, facilitating the agreement of the cross-sectoral consensus, and building a high-level leadership group; (2) optimizing the current human and livestock treatments in the national schistosomiasis control program of China; (3) developing highly sensitive and specific diagnostics and the framework for verifying elimination of schistosomiasis; (4) accelerating the progress towards elimination of schistosomiasis and other parasitic diseases through integrating the national control programs for other parasitic diseases.

Study on rapid recognition technique of schistosome susceptibility water bodyⅠAnimal skin making and effect assessment / 中国血吸虫病防治杂志

Objective To develop a bionic animal skin and evaluate its detective effect of Schistosoma japonicum cercariae so as to provide a new technique for the monitoring of the schistosome susceptibility water body.Methods A bionic animal skin was made with pigskin and the experiments were carried out for evaluating its detective effects of S.japonicum cercariae in labo-ratory and simulate fields,and at the same time,the sentinel mouse method was used as the control.Results In the laborato-ry,the cercariae were found in 10-,30-,60-cercaria subgroups in the bionic animal skin group after 1 and 2 hours,but the cer-cariae were found only in the 60-cercaria subgroup in the sentinel mouse group.In the simulate fields,in the water body with 5 schistosome-infected Oncomelania hupensis snails,the cercariae were found in 2 bionic animal skin devices(2/4)and 3 bionic animal skin devices(3/4)after 2 hours and 4 hours respectively,and in the water body with 10 schistosome-infected O.hupensis snails,the cercariae were found in 4 bionic animal skin devices(4/4)and 3 bionic animal skin devices(3/4)after 2 hours and 4 hours respectively in the bionic animal skin group.In the the sentinel mouse group,in the above-mentioned water bodies(with 5 or 10 schistosome-infected O.hupensis snails),the cercariae were found in 2 sentinel mice(2/4)and 1 sentinel mice(1/4)af-ter 2 hours and 4 hours respectively;and the cercariae were found in 2 sentinel mice(2/4)and 3 sentinel mice(3/4)after 2 hours and 4 hours respectively.Conclusion The bionic animal skin device can be used to detect the S.japonicum cercariae, and its sensibility and efficiency are superior to the traditional sentinel mouse method.

Challenge and strategy of prevention and control of important parasitic dis-eases under the Belt and Road Initiative / 中国血吸虫病防治杂志

China was once a country with the heaviest burden of parasitic diseases.Under the leadership of the Communist Party and national authority,after more than 60 years'efforts of prevention and control,the remarkable results have been achieved in China.However,affected by the social and economic development and environmental changes,the prevention and control of parasitic diseases,especially imported parasitic diseases,are facing new challenges,and the parasitic diseases,such as malaria,schistosomiasis,leishmaniasis,filariasis and trypanosomiasis,appear increasingly. With the development of the Belt and Road Initiative,the transmission risks of these diseases are more increased.The purpose of this paper is to describe the experience and results of parasitic disease prevention and control in China,understand the present parasitic disease epidemic situation of the Belt and Road Initiative related countries,analyze the transmission risks of important parasitic diseases,and present some relevant suggestions,so as to provide the evidence for the health administrative department formulating the preven-tion and control strategies of such parasitic diseases timely and effectively.

Evaluation standards and application for photography of schistosomiasis control theme / 中国血吸虫病防治杂志

Objective To set up and apply the evaluation standards for photography of schistosomiasis control theme,so as to offer the scientific advice for enriching the health information carrier of schistosomiasis control.Methods Through the litera-ture review and expert consultation,the evaluation standard for photography of schistosomiasis control theme was formulated. The themes were divided into 4 projects,such as new construction,natural scenery,working scene,and control achievements. Results The evaluation criteria of the theme photography were divided into the theme(60%),photographic composition (15%),focus exposure(15%),and color saturation(10%).A total of 495 pictures(sets)from 59 units with 77 authors were collected from schistosomiasis epidemic areas national wide.After the first-step screening and second-step evaluation,the prizes of 3 themes of control achievements and new construction,working scene,and natural scenery were selected,such as 6 pictures of first prize,12 pictures of second prize,18 pictures of third prize,and 20 pictures of honorable prize.Conclusions The eval-uation standards of theme photography should be taken into the consideration of the technical elements of photography and the work specification of schistosomiasis prevention and control.In order to improve the ability of records for propaganda purpose of schistosomiasis control and better play a role of guiding correct propaganda,the training and guidance of photography of profes-sionals should be carried out.

The impact of water level changes on the Oncomelania snail habitats in Poyang Lake regions before and after the impoundment of Three Gorges reservoir / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the impact of the impoundment of Three Gorges reservoir on Oncomelania snail habitats of Poyang Lake.</p><p><b>METHODS</b>Four counties with schistosomiasis endemic around the Poyang Lake, naming as Xingzi, Duchang, Jinxian and Xinjian, were selected as study areas. The average daily water level of four major hydrological stations near the above 4 counties from 1997 to 2008 were collected, as well as the elevation of 215 marshlands with snails in those 4 counties, the data of schistosomiasis endemic situation and snail survey of 4 counties in the year before the impoundment of Three Gorges reservoir (2002) and the 6th year after the impoundment of Three Gorges reservoir (2008). The fluctuations of water levels of Poyang Lake, flooding day of marshland with snails as well as the changes of the indicators in snail survey and prevention and control measures before and after the impoundment of Three Gorges reservoir were compared.</p><p><b>RESULTS</b>Before the impoundment of Three Gorges reservoir, the fluctuations of average water level of the four hydrological stations around Poyang Lake was 6.91-12.93 m; which reduced to 5.72 - 10.75 m after the impoundment. The D-value of the fluctuations of average water level was (1.06 ± 0.47) m. The date of the annual maximum water level delayed by an average of 12 d; while the date of annual minimum water level arrived an average of 12 d earlier than the impoundment of Three Gorges reservoir. The average flooding days of marshland with snails were separately (100.04 ± 42.06) d before the impoundment and (64.13 ± 22.30) d after the impoundment. The difference was statistically significant (t = 3.70, P < 0.05). The density of snails in the 4 counties around Poyang Lake was 0.8437/0.1 m(2) after the impoundment; declining by 31.04% from the snail density (1.2234/0.1 m(2)) before the impoundment. The density of infectious snails was 0.0014/0.1 m(2) after the impoundment; dropping by 67.34% from it (0.0042/0.1 m(2)) before the impoundment; the infection rate of snails was separately 0.34% after the impoundment and 0.16% before the impoundment. The difference was statistically significant (χ(2) = 53.25, P < 0.05). The coverage rate of chemotherapy increased from 4.45% (35 558/798 200) in 2002 to 9.80% (79 457/810 400) in 2008; the difference was statistically significant (χ(2) = 17 336.63, P < 0.05). The coverage rate of snail killing increased from 1.35% (389.04/28 824.66) in 2002 to 7.49% (2260.90/30 166.22) in 2008; the difference was also statistically significant (χ(2) = 28 824.66, P < 0.05).</p><p><b>CONCLUSION</b>The impact of the impoundment of Three Gorges reservoir shortened the flooding days of marshland with snails and helped the prevention and control of schistosomiasis in Poyang Lake regions as the environment went against the breeding of the snails.</p>

The impact of water level changes on distribution of snails around lake areas reacted by thematic mapper images / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the impact of water level changes on the distribution of snails around lakes, and to study the possibility of forecasting the distribution of snails according to changes of water level reacted by remote sensing images.</p><p><b>METHODS</b>All information including water level information of Xingzi Hydrometric Station from 1997 to 2007, twelve TM images of Poyang Lake between 1998 and 2006 were collected. The water areas of Poyang Lake was extracted by MNDWI threshold approach, and the relationships between water areas from TM images and water level from Hydrometric Station was analyzed; Majiawan and Menqiantan marshland of Zhuxi village, Xingzi county was chosen as study pilot to set frames and investigate snails 2991 frames in 2007, and the information of snails of this pilot from 1998 to 2006 was collected to analyze the relationships between snails and water level.</p><p><b>RESULTS</b>The water areas of Poyang Lake extracted from Remote Sensing images from 1998 to 2006 was 1658.73 - 5873.48 km(2), and the corresponding daily water level of Xingzi Hydrometric Station was 9.96 - 21.72 m, according to correlation analysis, they were positive correlation relationship, the correlation coefficient was 0.96 (P < 0.01), and build a model: S = 5189.96 x ln(h) - 10 284.97; the percent of frames with living snail of zhuxi pilot from 1998 - 2007 was 28.33% - 77.46%, the corresponding monthly average water level of last August was 13.19 - 21.96 m, the corresponding highest water level of last year was 15.97 - 21.96 m, according to correlation analysis. The percent of frames with living snail of zhuxi pilot was negatively correlated with the corresponding monthly average water level of last August and the corresponding highest water level of last year, and the correlation coefficient was -0.69 (P < 0.05), and -0.77 (P < 0.01) respectively.</p><p><b>CONCLUSION</b>Water areas of Poyang Lake extracted from remote sensing images could well express the actual changes of water level, and the highest water level ahead of the year investigating snails influence the distribution of snails, thus we can estimate the distribution of snails around lakes by remote sensing images.</p>

The effect and influencing factors of schistosomiasis control by forbidding livestock denaturing on marshland with Oncomelania snails / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluate the effect of schistosomiasis control by forbidding livestock denaturing on marshland with Oncomelania snails and to analyse its influencing factors.</p><p><b>METHODS</b>The village of Aiguo, Xinhe, Huangjia, Fanrong, Fengfu and Caomen and its respective nearby marshland, i.e., Aiguoniu, Liulingwei, Huangjianiu, Da, Goulian, and Litouzui, in Jinxian county, Jiangxi province were selected as the pilot areas for implementing the measures of forbidding livestock denaturing on the marshlands with Oncomelania snails during the period of the year 2005 to 2007. A total of 300 residents in each village were randomly chosen for stool examination with the Kato-Katz technique every year. The snail survey was carried out in spring and autumn every year on the marshlands close to the villages with systemic sampling method. The marshlands with a height 16.5 m above the sea level in Futian was selected for snail survey and planting with sesame. The residents aged 20 - 50 years old in Fengfu and Aiguo villages were studied by using questionnaire on the compliance of forbidding livestock pasturing on marshlands with Oncomelania snails.</p><p><b>RESULTS</b>Before implementation of the measures, human infection rate with Schistosoma japonicum was 11.35% (90/793) in Aiguo, 4.00% (12/300) in Xinhe, 4.00% (6/150) in Huangjia, 8.00% (12/150) in Fanrong, 3.17% (4/126) in Fengfu and 6.64% (14/211) in Caomen. After implementation in 2008, human schistsome infection rate in the aforementioned 6 villages was declined to 0.18% (1/551), 0.00% (0/348), 0.00% (0/316), 2.27% (7/308), 1.17% (5/428) and 1.16% (5/430), respectively. Only in Fengfu village the decline of the human prevalence was not significant (χ(2) = 2.4, P = 0.12), while in the other 5 villages, human prevalence rate had been declined significantly (χ(2) = 126.77, P < 0.01; χ(2) = 16.31, P < 0.01; χ(2) = 18.79, P < 0.01; χ(2) = 10.39, P < 0.01; χ(2) = 14.17, P < 0.01, respectively). Infected snails were not found in 5 out of the 6 marshlands close to the villages. Three infected snails were founded in Da marshland because of poor environmental isolation. Before planting, the living snail density was 0.063/0.11 m(2) (34/540), and after planting, the living snail density was 0.0074/0.11 m(2) (4/538), a 88.25% reduction (Z = 12.47, P < 0.01) was recorded through economy crop planting at Futiandaan marshland in 2008. A total of 986 pieces of questionnaire were provided, and 968 valid ones were collected. The results of questionnaire indicate that compliance of forbidding livestock denaturing on marshland with Oncomelania snails in Aiguo and Fengfu villages was 84.38% (216/256) and 75.42% (537/712), respectively. Using logistic regression model, knowledge level on harmfulness of livestock denaturing on marshland with Oncomelania snails, willingness of culture with machine to substitute traditional cattle culture, and willingness of investment to marshland culture development are 3 varieties that affect residents' implementation of forbidding livestock denaturing on marshland with Oncomelania snails.</p><p><b>CONCLUSION</b>The infected snail density and human schistosome infection rate were reduced on the marshlands of well environmental isolation after 2 - 3 years implementation of forbidding livestock denaturing on marshlands with Oncomelania snails. The key influencing factors of forbidding livestock denaturing on marshland with Oncomelania snails are knowledge level on harmfulness of livestock denaturing on the snail infested marshlands, the willingness of machine culture to substitute cattle culture, and the willingness of investment to marshland culture development.</p>

Integrated detection and analysis on the dusters of schistosomiasis based on geographic information system / 中华流行病学杂志

Objective To detect and analyze the clusters of schistosomiasis on marshland and lake areas based on geographic information system (GIS) in 2008 and to provide suggestions for the development of integrated methodology on the detection of clusters on related diseases. Methods Moran' s I of global spatial autocorrelation, Getis-Ord Gi of local spatial autocorrelation and SaTScan were used to detect the schistosomiasis clusters based on GIS and comparison of the results for different methods were performed. Results Results from the global Moran' s I tests for all the marshland and lake areas related to the schistosomiasis were statistically significant (P＜0.05)and indicated spatial heterogeneity; the z-score outcomes as calculated by Getis-Ord Gi indicated high cluster that 50 clusters were categorized at the 0.05 significance level and the z-score of these 45 clusters were more than 0. Results of SaTScan statistics appeared the same as local spatial autocorrelation and almost showing the existence of 5 cluster areas. Conclusion The geographical distribution of clusters where schistosomiasis was prevalent showed that it was closely corresponded to the middle and lower Yangtse river and in particular, many clusters were located near the boundary of Hubei and Hunan province.

Efficacy and adverse effects of film coated praziquantel for treatment of schistosomiasis japonica / 中华预防医学杂志

<p><b>OBJECTIVE</b>To understand the adverse and curative effects of film coated praziquantel for treatment of schistosomiasis japonica.</p><p><b>METHODS</b>A questionnaire survey was conducted among 6 to 65 years old inhabitants from epidemic areas of schistosomiasis japonica in Jiangxi, Anhui and Hubei provinces, while indirect haemagglutination assay (IHA) was also administrated. The Serological positives were tested by Kato-Katz technique. A total of 509 habitats of serological positives and healthy persons were given praziquantel. 460 targets with no relative symptoms were followed up for adverse effect of drugs in one month and efficacy evaluation of praziquantel was carried out in 104 parasitological positives 3 months post-treatment.</p><p><b>RESULTS</b>The 84.7% (144/170) individuals thought film coated tablets were no smell or only with little smell while 92.9%(315/339) targets in control group fell that tablets smelled bad. The total side effect rates of film coated praziquantel group and control group in 1-2 hours post-treatment were 20.30% (27/133) and 83.18% (272/327) respectively. There was significantly different between two groups (chi(2) = 164.316, P < 0.05). The adverse effect rates of film coated praziquantel group in neuromuscular system, digestive system and cardiovascular system were 15.79% (21/133), 9.77% (13/133), 2.26% (3/133) individually which were significantly lower than those of control groups with 81.65% (267/327), 49.24% (161/327), 12.84% (42/327) in corresponding systems (chi(2)(neuromuscular system) = 175.188, chi(2)(digestive system) = 62.601, chi(2)(cardiovascular system) = 12.010, P < 0.05). And the adverse effect rate of allergic reaction of film coated group was no significant difference with control group (2.26%(3/133) versus 0.92% (3/327), chi(2) = 1.315, P = 0.235). One day after treatment, the adverse effect rate of film coated tablets of praziquantel decreased to 3.01% (4/133), significantly lower than that of control group (P < 0.05). There was no significant difference after 2 weeks treatment while the adverse effect rates decreased to 0.75%(1/133), 0.61% (2/327) in film coated praziquantel group and control group respectively (chi(2) = 0.029, P = 0.642). The curative rates 3 months post treatment were 84.91% (45/51) in film coated tablets of praziquantel group and 82.35% (42/53) in control group without significant difference (chi(2) = 1.536, P = 0.215).</p><p><b>CONCLUSION</b>The smell and adverse effects of film coated tablets of praziquantel were decreased significantly and its efficacy for treatment of schistosomiasis japonica was equal to the control tablets. The film coated tablets of praziquantel might be applied in field widely after a further verification.</p>

Schistosomiasis in China: acute infections during 2005-2008 / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Significant progress has taken place over the past 50 years in the control of schistosomiasis japonica in China. However, the available data suggested that schistosomiasis has re-emerged shortly after the World Bank Loan Project which was conducted from 1992 to 2001. The national control program with a revised strategy to control schistosomiasis by using integrated measures has been implemented since 2005. In this study, we aimed to evaluate the effect of the national program on schistosomiasis control from 2005 to 2008.</p><p><b>METHODS</b>A retrospective study was carried out to analyze the epidemic patterns of acute infections with Schistosoma japonicum (S. japonicum), based on the number of acute cases annually collected from the web-based national communicable diseases reporting system from 2005 to 2008.</p><p><b>RESULTS</b>A total of 564, 207, 83 and 57 acute cases infected with S. japonicum were reported nationwide in 2005, 2006, 2007 and 2008, respectively, with an average annual reduction rate of 46.35% during last four years. Six outbreaks of acute infection with S. japonicum were reported in 2005 but none in the period of 2006 to 2008. All acute cases that were reported mainly came from the lake regions and became infected during the higher risk periods from the 27th to 43rd weeks of the year. Most of these cases are students (44.87%), farmers (31.51%) and fishermen (7.79%) who got the infection by water contact mainly through swimming (41.49%) and production activities (40.25%). With time, the proportion of imported cases among all acute cases increased due to more frequent movement of people that has occurred with a more mobile population.</p><p><b>CONCLUSIONS</b>The national control program on schistosomiasis aliened with the revised control strategy has been effectively brought into effect. However, there is still a significant risk of infection among students, farmers and fishermen living in the lake regions. Therefore, it is important to strengthen control measures among risk populations in the high risk areas of transmission, or the lake regions.</p>

Infectious status of infection sources in the epidemic regions of Schistosomiasis japonica in China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To understand the infectious status of infection sources in some epidemic regions of Schistosomiasis japonica, and provide a scientific basis for further controlling infection sources in a comprehensive way.</p><p><b>METHODS</b>Longshang village which lies in the area of hills and mountains and Yuye village which lies in the area of lakes and marshlands were chosen for field investigation. The study was targeted at snails and 1512 residents, while 197 samples of livestock were randomized (80 cattle, 46 pigs, 45 dogs, 18 cats, 8 sheep) and 32 wild animals (field rats) were screened in Anhui province between October to November in 2007. The infection rate and intensity of infection were calculated after pathogenic examination on the populations, livestock and wild animals (field rats).</p><p><b>RESULTS</b>(1) The infection rate of snails in Longshang and Yuye village were 2.26%, 1.06% in 2007, and 0.55%, 0.72% in 2006 respectively. (2) Of the infection rate and geometric mean of egg per gram (EPG) of population, 3.8% and 0.14 (EPG) were in Longshang village and 3.4% and 0.13 (EPG) were in Yuye village. The positive rate of blood examination of the different sex in Longshang village was 17.5% (44/252) of the males, higher than that of the females 11.0% (25/227) (chi(2) = 4.026, P = 0.045), whereas, in Yuye village was 21.4% (66/309) of males and 19.4% (25/129) for the females, without significant differences (chi(2) = 0.217, P > 0.05). The positive rate of fecal examination of the different sex in Longshang village was 5.2% (14/268) of the men and 2.1% (5/236) of the women showing no statistical significance (chi(2) = 3.336, P > 0.05); whereas, in Yuye village was 5.7% (14/245) of the men and 1.2% (3/250) of the women (chi(2) = 7.603, P = 0.006). (3) The infection rate and the arithmetic mean of EPG of the cattle, 10.8% (8/74) and 135.00 (EPG) were in Longshang village, meanwhile, the infection rate of the bull was 9.1% (6/66) and 25.0% (2/8) for cow without statistical significance (chi(2) = 0.586, P = 0.444), whereas, the total number of cattle was 6 that had been examined and there was no positive case in Yuye village. Of 8 sheep examined in Yuye village, 6 was positive, with arithmetic mean of 254.82 (EPG), while there was no sheep in Longshang village. (4) Of the positive rate of the incubation for dog's feces and intensity of infection, 55.6% (24/36) and 20.00 (EPG) were in Yuye village whereas 23.81% (5/21) and 1.21 (EPG) were in Longshang village. (5) Of the infection rate of the field rats, 13.64% (3/22) in Longshang village whereas a total number of mouse was 10 that had been examined and there was no positive case in Yuye village.</p><p><b>CONCLUSION</b>The farm cattle should be still the chief sources of infection in the regions of lakes and marshlands for schistosomiasis. Whereas, with the implementing in-depth of the strategy on controlling source of infection in a integrated way, high priorities should be given to the epidemiological factors of the animals such as sheep, dogs, field mouse and so on which are spreading schistosomiasis.</p>

Impact of people's social behavior on schistosomiasis transmission in the Three Gorges Reservoir area / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the changes in natural ecology and social environment after the construction of the dam in the Three Gorges Reservoir area, and to understand the social behavior status and education backgrounds of the local residents, and to analyze the potential impact of these factors on schistosomiasis spreading.</p><p><b>METHODS</b>Data of nature and social economy after the construction of the dam in the Three Gorge area were collected, and a cross-sectional study with questionnaire survey on information including social demographic characteristics, people's production and life style, knowledge about schistosomiasis was conducted among natives, emigrations.</p><p><b>RESULTS</b>After the construction of the dam, as the stream became slower, the water-level fluctuating zone on the bank of the reservoir was formed. The main source of drinking water and daily life activity are mainly depends on the river supplying (accounting about 68.7% and 75.8%, respectively); due to the needs of farming, washing cloths and vegetables, 45.6% of resident had a close contact with river water. People with away-from-home employment among emigrations were increased from 5.7% to 18.7%. The proportion of using hygienic lavatory was 88.6%. The main source of water for drinking and daily life among emigrations was tap water (85.4% and 87.0%). The residents had no awareness about the health hazard for schistosomiasis, with less health information</p><p><b>CONCLUSION</b>The natural environment of reservoir areas and the life style are risk factors for the spread of schistosomiasis. The improved sanitation condition and the economy construction after the construction of the dam is propitious to keeping away from the introduction of schistosomiasis. However, people with away-from-home employment among emigrations are still at risk of schistosomiasis.</p>

A study of environmental changes on new snail habitat though multi-temporal relative radiometric normalized TM images / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the environmental changes of new snail habitual by using multi-temporal relative radiometric normalized TM images taken in Wuzhoutou of Nanchang, Jiangxi province.</p><p><b>METHODS</b>TM images of Poyang Lake were collected on 3rd April 1998, 16th April 2000 and 5th May 2004. Taking images in 2004 as a reference, the TM images in 1998 and 2000 were radiometric normalized. The images were analyzed to trace the vegetation background and snail historical information.</p><p><b>RESULTS</b>The vegetation coverage rate of Wuzhaoutou on April 3rd in 1998 was 4.76%, but the vegetation coverage rates of Wuzhoutou on April 16th in 2000 and May 5th in 2004 were above 80%; the NDVI values of Wuzhoutou on April 3rd in 1998 were around -0.4 to 0.2, but the NDVI values of Wuzhoutou on April 16th in 2000 and May 5th in 2004 were mainly around 0.2 to 0.6, which had statistical difference with that in 1998 (q = 162.285321, P < 0.01 and q = 161.669725, P < 0.01). The greenness of three images have statistical differences(q = 178.679245, P < 0.01; q = 130.320755, P < 0.01 and q = - 48.358491, P < 0.01).</p><p><b>CONCLUSION</b>Combining with the snail survey, the TM images could be an effective measure for setting up models to forecast the areas where snails might live to control the Schistosomiasis epidemic.</p>

Application of globe geographical positioning with wireless communication monitoring and supervision system in field survey on the endemic of schistosomiasis / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluate the practical value and the advantages of globe geographical positioning with wireless communication monitoring and supervision system in the field survey.</p><p><b>METHODS</b>Spots which were randomly sampled by the National Ministry of Health for the investigation were chosen in the endemic areas for schistosomiasis in Jiangsu, Jiangxi, Anhui, Hunan, Hubei, Sichuan and Yunnan provinces. Portable GPS CEC9680 was used for collecting relevant waypoints and track, recording on-the-spot geographical positions. The positioning data package was sent back synchronously in the form of short message of SMS to the monitoring service center, and the moving routes of the terminal receiver monitored were displayed on the GIS map to achieve real-time supervision and staff scheduling.</p><p><b>RESULTS</b>With globe geographical positioning with wireless communication monitoring and supervision system, accurate positioning of 12 spots in the provinces of Jiangsu and 3 trial spots for schistosomiasis control with comprehensive treatment designated by the State Council has been established with real-time communicating recording, and monitoring systems.</p><p><b>CONCLUSION</b>The globe geographical positioning with wireless communication monitoring and supervision system has provided a technical platform for the survey of schistosomiasis and other infectious diseases.</p>

Application of global positioning system and geographic information system in surveillance of schistosomiasis / 中华预防医学杂志

<p><b>OBJECTIVE</b>To use the snail survey data of Yugan, Jiangxi Province as an example to evaluate the effects and advantages of global positioning system integrated with digital maps and remote sensing data in order to manage and analyze the whole country's surveillance data of schistosomiasis by using geographic information system.</p><p><b>METHODS</b>The data of geographic information and snail information of 20 marshlands in Yugan, Jiangxi Province were collected, and by the correction of remote sensing images based on the digital maps and index extraction, the snail current situation and trend were analyzed and expressed.</p><p><b>RESULTS</b>A series of specific procedure images of these 20 marshlands was established and the effects of Yugan surveillance platform based on geographic information system were validated.</p><p><b>CONCLUSION</b>The whole country's surveillance data of schistosomiasis might be successfully integrated with geographic information system by global positioning system and be managed and expressed, which supplies a successful platform in using the surveillance data effectively.</p>

Effects of land surface temperature on supervising the existing area of snails / 中华预防医学杂志

<p><b>OBJECTIVE</b>To discuss the land surface temperature's effect on supervising the areas with snails, comparing the land surface temperature (LST) of the areas with snails with the LST of those without snails.</p><p><b>METHODS</b>Choosing the lake areas of farmland in Jiangxi Province and the beach in the bank of Ganjiang, dividing into four areas according to snails. Picking up the normalized difference vegetation index (NDVI) and LST from the remote sensing data to find the difference between the areas with snails and the areas without snails, so as to illuminate the effects of the LST on distinguishing the areas with snails.</p><p><b>RESULTS</b>The NDVI of Dongfeng Wei (an area from farmland to lake) was 0 - 0.20, the NDVI of the areas with snails was 0.20 - 0.40. The NDVI of four areas is different (chi(2) = 104.69, P < 0.01). The LST of Dongfeng wei was 24 - 30 degrees C, Wuzhoutou without snails is 23 - 28 degrees C, Wuzhoutou with snails is 22 - 26 degrees C, Changjiangzhou was 20 - 24 degrees C. The LST of four areas is different (chi(2) = 115.23, P < 0.01). The analysis farther indicates the NDVI of areas without snails was lower than that of areas with snails, but the LST was higher.</p><p><b>CONCLUSION</b>The NDVI and (or) the LST should be significantly different between the areas with snails and the areas without, it might be concluded that the LST should be a indication to some extent on judging whether some areas may be fit for snails.</p>

The current status of schistosomiasis epidemics in China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To analyze the change of tendency on schistosomiasis epidemics in China in the last 5 years.</p><p><b>METHODS</b>Data on schistosomiasis epidemics in the history and particularly in the last 5 years were collected. Tendency and the re-emerging status after 1998 were analyzed.</p><p><b>RESULTS</b>Data in 2003 showed that in 42%, 40% and 53% of the provinces, counties and townships with epidemics, the transmission of the disease has been interrupted or controlled. The number of estimated patients of schistosomiasis and areas with snails were also reduced by 92.74% and 73.56%, in 2003. The annual estimated number of chronic cases was around 800 000 and 31 321.5 hectare of snail infested areas were newly identified in recent 5 years. Among 20 national villages under longitudinal surveillance, 30%, 70% and 35% of the villages were presented a tendency of increase in the rates of human infection, bovine infection and Oncomelania snails infection, respectively. A total of 38 counties from 7 provinces have re-emerged in schistosomiasis transmission after those counties having reached criteria of transmission under control or interrupted. In 6 non-endemic counties, snails were presented, and 16 marshlands in Xan river were found with appearance of acute cases of schistosomiasis. More snail infested areas were found in Shanghai, Zhejiang, and Fujian. Both snail infested areas and newly infected cases were occurred in urban areas along the Yangtze River.</p><p><b>CONCLUSION</b>The tendency of increase was presented in focal areas along the Yangtze River, due to changes of environmental, ecological, societal and economic status, as well as on the forces of control.</p>