ABSTRACT
Objective To understand the real prevalence of Clonorchis sinensis infections in the freshwater fish in mainland China, so as to provide insights into clonorchiasis control and detection of freshwater fish. Methods All literatures reporting the prevalence of C. sinensis infections in the freshwater fish, the second intermediate host of the parasite, were jointly retrieved in Chinese and English electronic databases from January 1, 2010 to December 31, 2020, including Wanfang Data, CNKI, PubMed, Web of Science, Embase and Cochrane Library. All studies were screened based on inclusion and exclusion criteria, and the quality of all enrolled literatures was evaluated. The pooled prevalence of C. sinensis infections in freshwater fish and its 95% confidence interval (CI) were estimated using the software Stata version 15.0, and subgroup analyses were performed to investigate the region-, season- and sample source-specific pooled prevalence of C. sinensis infections in freshwater fish. In addition, the sensitivity and publication bias of all included studies were analyzed. Results A total of 40 eligible literatures were included in this study, including 37 Chinese literatures and 3 English literatures, and there were 10 high-quality literatures, 27 moderate-quality literatures and 3 low-quality literatures. A total of 53 species containing 37 959 freshwater fish were reported in these 40 studies, and 73.58% (39/53) of freshwater fish species were identified with C. sinensis infections. Meta-analysis showed 23.5% [95% CI: (0.19, 0.28)] pooled prevalence of C. sinensis infections in freshwater fish in mainland China, and subgroup analyses higher prevalence of C. sinensis infections in freshwater fish in northeastern China [35.7%, 95% CI: (0.22, 0.50)] than in central [25.9%, 95% CI: (0.04, 0.48)] and southern China [20.6%, 95% CI: (0.09, 0.32)], higher prevalence of C. sinensis infections in freshwater fish sampled in spring [44.1%, 95% CI: (0.35, 0.53)] than in autumn [6.7%, 95% CI: (0.05, 0.08)] and summer [3.3%, 95% CI: (−0.01, 0.07)], and higher prevalence of C. sinensis infections in freshwater fish sampled from natural water [25.2%, 95% CI: (0.17, 0.33)] than from retail trades [22.2%, 95% CI: (0.17, 0.28)] and breeding chain [12.3%, 95% CI: (0.03, 0.22)]. However, all included studies had a publication bias with a low sensitivity. Conclusions The prevalence of C. sinensis infections is high in freshwater fish in mainland China, and there are still challenges for clonorchiasis control. Reinforcement of health education, diagnostics development and food safety supervision is recommended in future clonorchiasis control programs.
ABSTRACT
This report presented the endemic status of schistosomiasis in the People’s Republic of China at a national level in 2018, and analyzed the data collected from the national schistosomiasis prevention and control system and 453 national schistosomiasis surveillance sites. Among the 12 provinces (municipality and autonomous region) endemic for schistosomiasis in China, 5 provinces (municipality and autonomous region), including Shanghai, Zhejiang, Fujian, Guangdong and Guangxi, continued to consolidate the achievements of schistosomiasis elimination, Sichuan Province achieved transmission interruption and 6 provinces of Yunnan, Jiangsu, Hubei, Anhui, Jiangxi and Hunan achieved transmission control by the end of 2018. There were 450 endemic counties (cities, districts) covering 260 million people, specifically including 28 456 endemic villages covering 70.059 7 million people at risk of infection. Among the 450 endemic counties (cities, districts), 58.44% (263/450), 27.56% (124/450) and 14.00% (63/450) reached the criteria of elimination, transmission interruption and transmission control, respectively. By the end of 2018, a total of 29 214 advanced schistosomiasis cases were documented in China. In 2018, a total of 11.127 6 million individuals received inquiry examinations and 2.062 9 million were positive; 7.191 4 million individuals received serological tests and 138.5 thousand of them were positive, 532.2 thousand individuals received stool examinations and 8 were positive in China. In 2018, snail survey was performed in 19 821 endemic villages and Oncomehania snails were found in 7 321 villages, accounting for 36.94% of all surveyed villages, with 3 newly detected villages with snails in China. Snail survey covered an area of 590 241.01 hm2 and 168 319.41 hm2 snail habitats were found, including emerging snail habitats of 61.28 hm2; however, no infected snails were identified. In 2018, a total of 646 823 bovines were raised in the schistosomiasis endemic areas of China, and 225 258 received serological examinations, with 2 638 positives detected, while 164 803 bovines received stool examinations, with 2 positives identified. In 2018, there were 90 388 patients with schistosomiasis receiving praziquantel chemotherapy, and expanded chemotherapy was given to 1 490 594 person-times; there were two bovines with schistosomiasis receiving praziquantel chemotherapy, and expanded chemotherapy was given to 352 577 bovine-times; chemical treatment was conducted in an area of 141 660.87 hm2, including an actual mollusciciding area of 75 308.26 hm2, and environmental improvements were performed in an area of 4 738.37 hm2 in China. Data from the 453 national schistosomiasis surveillance sites of China showed that the mean Schistosoma japonicum infection rates were 0.001 5% and zero in humans and bovines in 2018, respectively, and no infected snails were found. The results demonstrate that the endemic situation of schistosomiasis appears a tendency towards a continuous decline in China; however, there is still a risk of schistosomiasis transmission, and challenges remain in achieving the target set in the Thirteenth Five-Year National Plan for Schistosomiasis Control in 2020 in some regions.
ABSTRACT
Objective To understand the epidemic trend of schistosomiasis in China from 2010 to 2017 so as to provide the scientific evidence for schistosomiasis elimination. Methods The information of schistosomiasis control nationwide from 2010 to 2017 was collected, including the endemic of population, status of livestock control, and Oncomelania hupensis snail control. Microsoft Excel was applied for datum management and analysis. Results From 2010 to 2017, the epidemic of schistosomiasis in China dropped significantly. The decreasing amplitude of estimated number of patients nationwide was 88.46%. Seventy-one acute schistosomiasis patients were reported and 12.68% (9/71) of them were imported. The decreasing rate of cultivated cattle was 50.09%, and the accumulative number of schistosome-infected cattle was 17 239, and the average positive rate of stool examinations decreased from 1.04% to 0.000 22%. The area with snails nationwide was 373 596.18 to 363 068.95 hm2, and the new detected area with snails was 46.71 to 1 346.73 hm2. The area with schistosome-infected snails was 171.68 hm2 in 2012 and it was 9.25 hm2 in 2013. In 72 key monitoring points of 7 endemic provinces, there were 17 schistosome positive points of water body in 2010 and 6 points in 2016. There were some high risk-factors related to schistosomiasis transmission including schisto-some-infected cattle, dogs, and field rats, and the field stools, and the pasture in the area with snails in schistosomiasis monitoring points. Conclusions The endemic status of schistosomiasis in China has dropped significantly, and the transmission level is very low. However, the infectious source and risk factors in the endemic environments have not be eliminated. Therefore, the infectious source control, health education, snail control, and transmission monitoring should be strengthened, so as to promote the progress of schistosomiasis elimination.
ABSTRACT
Objective To understand the reporting situation of schistosomiasis cases in National Notifiable Disease Report System (NNDRS) in China from 2015 to 2017, and to seek current deficiencies on case reporting as well as to analyze the epidemiological characteristics of schistosomiasis cases. Methods The data of schistosomiasis cases in China from 2015 to 2017 were collected from NNDRS, and the reporting situation and epidemiological characteristics of schistosomiasis cases were analyzed. Results From 2015 to 2017, totally 59 981 schistosomiasis cases were reported in China, among which, 1 460 cases were deleted, and 58 521 were censored cases. The statistics and analysis showed that a part of the case reporting had been carried out in nonstandard ways, mainly involving the random deletion of cases, reporting time not compliance with regulations, incorrect classification, and severe omission of cases. Among the 58 521 censored cases, the sex ratio of the male to the female was 1.83∶1, the average age of the cases was (51.91 ± 11.30) years, and farmers and fishermen accounted for 93.26% (54 577 cases) and 3.46% (2 022 cases), respectively. The reported cases mainly concentrated in Anhui, Hunan, Hubei and Jiangxi provinces, accounting for 99.73% of the total number in China. During this period, Beijing, Zhejiang and other provinces (cities and regions) reported 11 imported schistosomiasis cases, all of them were schistosomiasis mansoni cases or schistosomiasis haematobia cases. Conclusions From 2015 to 2017, the reported cases of schistosomiasis are mainly clinically diagnosed cases. Compared with the annual report of the national schistosomiasis control, the number of confirmed cases in NNDRS is seriously missed. Therefore, the endemic provinces should strengthen the supervision on confirmed cases and reporting quality of schistosomiasis cases in accordance with the relevant law and regulation.
ABSTRACT
Objective To understand the reporting situation of schistosomiasis cases in National Notifiable Disease Report System (NNDRS) in China from 2015 to 2017, and to seek current deficiencies on case reporting as well as to analyze the epidemiological characteristics of schistosomiasis cases. Methods The data of schistosomiasis cases in China from 2015 to 2017 were collected from NNDRS, and the reporting situation and epidemiological characteristics of schistosomiasis cases were analyzed. Results From 2015 to 2017, totally 59 981 schistosomiasis cases were reported in China, among which, 1 460 cases were deleted, and 58 521 were censored cases. The statistics and analysis showed that a part of the case reporting had been carried out in nonstandard ways, mainly involving the random deletion of cases, reporting time not compliance with regulations, incorrect classification, and severe omission of cases. Among the 58 521 censored cases, the sex ratio of the male to the female was 1.83∶1, the average age of the cases was (51.91 ± 11.30) years, and farmers and fishermen accounted for 93.26% (54 577 cases) and 3.46% (2 022 cases), respectively. The reported cases mainly concentrated in Anhui, Hunan, Hubei and Jiangxi provinces, accounting for 99.73% of the total number in China. During this period, Beijing, Zhejiang and other provinces (cities and regions) reported 11 imported schistosomiasis cases, all of them were schistosomiasis mansoni cases or schistosomiasis haematobia cases. Conclusions From 2015 to 2017, the reported cases of schistosomiasis are mainly clinically diagnosed cases. Compared with the annual report of the national schistosomiasis control, the number of confirmed cases in NNDRS is seriously missed. Therefore, the endemic provinces should strengthen the supervision on confirmed cases and reporting quality of schistosomiasis cases in accordance with the relevant law and regulation.
ABSTRACT
This report presented the endemic status of schistosomiasis in the People’s Republic of China at a national level in 2018, and analyzed the data collected from the national schistosomiasis prevention and control system and 453 national schistosomiasis surveillance sites. Among the 12 provinces (municipality and autonomous region) endemic for schistosomiasis in China, 5 provinces (municipality and autonomous region), including Shanghai, Zhejiang, Fujian, Guangdong and Guangxi, continued to consolidate the achievements of schistosomiasis elimination, Sichuan Province achieved transmission interruption and 6 provinces of Yunnan, Jiangsu, Hubei, Anhui, Jiangxi and Hunan achieved transmission control by the end of 2018. There were 450 endemic counties (cities, districts) covering 260 million people, specifically including 28 456 endemic villages covering 70.059 7 million people at risk of infection. Among the 450 endemic counties (cities, districts), 58.44% (263/450), 27.56% (124/450) and 14.00% (63/450) reached the criteria of elimination, transmission interruption and transmission control, respectively. By the end of 2018, a total of 29 214 advanced schistosomiasis cases were documented in China. In 2018, a total of 11.127 6 million individuals received inquiry examinations and 2.062 9 million were positive; 7.191 4 million individuals received serological tests and 138.5 thousand of them were positive, 532.2 thousand individuals received stool examinations and 8 were positive in China. In 2018, snail survey was performed in 19 821 endemic villages and Oncomehania snails were found in 7 321 villages, accounting for 36.94% of all surveyed villages, with 3 newly detected villages with snails in China. Snail survey covered an area of 590 241.01 hm2 and 168 319.41 hm2 snail habitats were found, including emerging snail habitats of 61.28 hm2; however, no infected snails were identified. In 2018, a total of 646 823 bovines were raised in the schistosomiasis endemic areas of China, and 225 258 received serological examinations, with 2 638 positives detected, while 164 803 bovines received stool examinations, with 2 positives identified. In 2018, there were 90 388 patients with schistosomiasis receiving praziquantel chemotherapy, and expanded chemotherapy was given to 1 490 594 person-times; there were two bovines with schistosomiasis receiving praziquantel chemotherapy, and expanded chemotherapy was given to 352 577 bovine-times; chemical treatment was conducted in an area of 141 660.87 hm2, including an actual mollusciciding area of 75 308.26 hm2, and environmental improvements were performed in an area of 4 738.37 hm2 in China. Data from the 453 national schistosomiasis surveillance sites of China showed that the mean Schistosoma japonicum infection rates were 0.001 5% and zero in humans and bovines in 2018, respectively, and no infected snails were found. The results demonstrate that the endemic situation of schistosomiasis appears a tendency towards a continuous decline in China; however, there is still a risk of schistosomiasis transmission, and challenges remain in achieving the target set in the Thirteenth Five-Year National Plan for Schistosomiasis Control in 2020 in some regions.
ABSTRACT
Objective To understand the epidemic trend of schistosomiasis in China from 2010 to 2017 so as to provide the scientific evidence for schistosomiasis elimination. Methods The information of schistosomiasis control nationwide from 2010 to 2017 was collected, including the endemic of population, status of livestock control, and Oncomelania hupensis snail control. Microsoft Excel was applied for datum management and analysis. Results From 2010 to 2017, the epidemic of schistosomiasis in China dropped significantly. The decreasing amplitude of estimated number of patients nationwide was 88.46%. Seventy-one acute schistosomiasis patients were reported and 12.68% (9/71) of them were imported. The decreasing rate of cultivated cattle was 50.09%, and the accumulative number of schistosome-infected cattle was 17 239, and the average positive rate of stool examinations decreased from 1.04% to 0.000 22%. The area with snails nationwide was 373 596.18 to 363 068.95 hm2, and the new detected area with snails was 46.71 to 1 346.73 hm2. The area with schistosome-infected snails was 171.68 hm2 in 2012 and it was 9.25 hm2 in 2013. In 72 key monitoring points of 7 endemic provinces, there were 17 schistosome positive points of water body in 2010 and 6 points in 2016. There were some high risk-factors related to schistosomiasis transmission including schisto-some-infected cattle, dogs, and field rats, and the field stools, and the pasture in the area with snails in schistosomiasis monitoring points. Conclusions The endemic status of schistosomiasis in China has dropped significantly, and the transmission level is very low. However, the infectious source and risk factors in the endemic environments have not be eliminated. Therefore, the infectious source control, health education, snail control, and transmission monitoring should be strengthened, so as to promote the progress of schistosomiasis elimination.
ABSTRACT
Single nucleotide polymorphisms (SNP) has been regarded as a new genetic marker due to its rich dynamics and relatively stable heredity. SNP can express the relationship between genes and diseases to seek disease-linked genes particularly. A number of domestic and international studies have demonstrated that the formation of schistosomiasis egg granuloma is closely linked to HLA-Ⅱ related antigen. By detecting alleles loci of HLA-Ⅱ gene, researchers can identify the gene or haplotype that is associated with the susceptibility and progression of schistosomiasis. The detected candidate genes can serve useful therapeutic and preventative purposes by providing new technical methods to defeat schistosomiasis. In-depth study on SNP is beneficial to evaluate schistosomiasis inclination clinically, as well as to promote early diagnosis and preventive treatment.
ABSTRACT
This report presents the endemic status of schistosomiasis in the People’s Republic of China at national level in 2017, and analyzes the data collected from the national schistosomiasis prevention and control system and 457 national schistosomiasis surveillance sites. Among the 12 provinces (municipality and autonomous region) being endemic of schistosomiasis japonica in P. R. China, 5 provinces (municipality and autonomous region), i.e., Shanghai, Zhejiang, Fujian, Guangdong and Guangxi, continued to consolidate the status of elimination of schistosomiasis. Sichuan Province achieved the transmission interruption and 6 provinces of Yunnan, Jiangsu, Hubei, Anhui, Jiangxi and Hunan kept the transmission control by the end of 2017. There were 450 endemic counties (cities, districts) covering 259 million people, specifically including 28 544 endemic villages of 70 324.5 thousand people at risk. Among the 450 endemic counties (cities, districts), 47.78% (215/450), 34.00% (153/450) and 18.22% (82/450) reached the criteria of elimination, transmission interruption and transmission control, respectively. By the end of 2017, a total of 8 401 113 individuals received schistosomiasis examinations and 14 individuals were parasitologically diagnosed, decreased by 97.67% compared with 600 cases in 2016. It was estimated of 37 601 cases of schistosome infection, decreased by 30.95% compared with 54 454 cases in 2016. One acute schistosomiasis case was reported in 2017. There were 29 407 advanced schistosomiasis cases documented in 2017. Oncomelania hupensis snail surveys were performed in 19 784 endemic villages and O. hupensis snails were found in 7 310 villages, accounting for 36.95% of total villages, with 19 newly detected villages with snails.The snail survey covered an area of 622454.49 hm2 and snails were found in an area of 172501.56 hm2, including a newly detected area of 208.54 hm2. No schistosome-infected snails were found in 2017. A total of 737 016 bovines were raised in the schistosomiasis endemic areas. Of them, 454 830 bovines received the examinations for schistosome infection, and 1 bovine was stool examination positive. There were 119 326 schistosomiasis cases receiving chemotherapy in 2017, with 1 973 968 individuals undergoing expanded chemotherapy; one bovine with schistosomiasis receiving chemotherapy, with 418 925 bovines undergoing expanded chemotherapy. A total of 144 605.31 hm2 area with snail was controlled by using molluscicides, with actual molluscicide-treated area of 73 755.37 hm2; and 5 002.92 hm2 area with snail was treated by environmental modification. Based on the data from the 457 national schistosomiasis surveillance sites, the mean Schistosoma japonicum infection rate was 0.001 6% and 0 in humans and bovines, respectively. No schistosome-infected snails were found by microscopic examinations in all the surveillance sites, and 7 snail samples with schistosome nucleic acid positive were detected by loopmediated isothermal amplification (LAMP) among 6 surveillance sites. The results demonstrate a continuous decline trend on the endemic situation of schistosomiasis in P. R. China. However, the risk of epidemic rebound still exists in some regions and it is still a challenge to achieve the target set by the Thirteenth Five-Year National Plan for Schistosomiasis Control in 2020.
ABSTRACT
Single nucleotide polymorphisms (SNP) has been regarded as a new genetic marker due to its rich dynamics and relatively stable heredity. SNP can express the relationship between genes and diseases to seek disease-linked genes particularly. A number of domestic and international studies have demonstrated that the formation of schistosomiasis egg granuloma is closely linked to HLA-Ⅱ related antigen. By detecting alleles loci of HLA-Ⅱ gene, researchers can identify the gene or haplotype that is associated with the susceptibility and progression of schistosomiasis. The detected candidate genes can serve useful therapeutic and preventative purposes by providing new technical methods to defeat schistosomiasis. In-depth study on SNP is beneficial to evaluate schistosomiasis inclination clinically, as well as to promote early diagnosis and preventive treatment.
ABSTRACT
This report presents the endemic status of schistosomiasis in the People’s Republic of China at national level in 2017, and analyzes the data collected from the national schistosomiasis prevention and control system and 457 national schistosomiasis surveillance sites. Among the 12 provinces (municipality and autonomous region) being endemic of schistosomiasis japonica in P. R. China, 5 provinces (municipality and autonomous region), i.e., Shanghai, Zhejiang, Fujian, Guangdong and Guangxi, continued to consolidate the status of elimination of schistosomiasis. Sichuan Province achieved the transmission interruption and 6 provinces of Yunnan, Jiangsu, Hubei, Anhui, Jiangxi and Hunan kept the transmission control by the end of 2017. There were 450 endemic counties (cities, districts) covering 259 million people, specifically including 28 544 endemic villages of 70 324.5 thousand people at risk. Among the 450 endemic counties (cities, districts), 47.78% (215/450), 34.00% (153/450) and 18.22% (82/450) reached the criteria of elimination, transmission interruption and transmission control, respectively. By the end of 2017, a total of 8 401 113 individuals received schistosomiasis examinations and 14 individuals were parasitologically diagnosed, decreased by 97.67% compared with 600 cases in 2016. It was estimated of 37 601 cases of schistosome infection, decreased by 30.95% compared with 54 454 cases in 2016. One acute schistosomiasis case was reported in 2017. There were 29 407 advanced schistosomiasis cases documented in 2017. Oncomelania hupensis snail surveys were performed in 19 784 endemic villages and O. hupensis snails were found in 7 310 villages, accounting for 36.95% of total villages, with 19 newly detected villages with snails.The snail survey covered an area of 622454.49 hm2 and snails were found in an area of 172501.56 hm2, including a newly detected area of 208.54 hm2. No schistosome-infected snails were found in 2017. A total of 737 016 bovines were raised in the schistosomiasis endemic areas. Of them, 454 830 bovines received the examinations for schistosome infection, and 1 bovine was stool examination positive. There were 119 326 schistosomiasis cases receiving chemotherapy in 2017, with 1 973 968 individuals undergoing expanded chemotherapy; one bovine with schistosomiasis receiving chemotherapy, with 418 925 bovines undergoing expanded chemotherapy. A total of 144 605.31 hm2 area with snail was controlled by using molluscicides, with actual molluscicide-treated area of 73 755.37 hm2; and 5 002.92 hm2 area with snail was treated by environmental modification. Based on the data from the 457 national schistosomiasis surveillance sites, the mean Schistosoma japonicum infection rate was 0.001 6% and 0 in humans and bovines, respectively. No schistosome-infected snails were found by microscopic examinations in all the surveillance sites, and 7 snail samples with schistosome nucleic acid positive were detected by loopmediated isothermal amplification (LAMP) among 6 surveillance sites. The results demonstrate a continuous decline trend on the endemic situation of schistosomiasis in P. R. China. However, the risk of epidemic rebound still exists in some regions and it is still a challenge to achieve the target set by the Thirteenth Five-Year National Plan for Schistosomiasis Control in 2020.
ABSTRACT
This report presents the endemic status of' schistosomiasis in the People ' s Republic, of China at national level in 2017, and analyzes the data collected from the national schistosomiasis prevention and control system and 457 national schistosomiasis surveillance sites. Among the 12 provinces (municipality and autonomous region) being endemic of schistosomiasis japonica in P. R. China, 5 provinces (municipality and autonomous region) , i.e., Shanghai, Zhejiang, Fujian, Guangdong and Guangxi, continued to consolidate the status of elimination of schistosomiasis. Sichuan Province achieved the transmission interruption and 6 provinces of Yunnan, Jiangsu, Hubei, Anhui, Jiangxi and Hunan kept the transmission control by the end of 2017. There were 450 endemic counties (cities, districts) covering 259 million people, specifically including 28 544 endemic: villages of 70 324.5 thousand people at risk. Among the 450 endemic counties (cities, districts) , 50.89% (229/450) , 30.89% ( 139/450) and 18.22% ( 82/450) reached the criteria of elimination , transmission interruption and transmission control, respectively. By the end of 2017 , a total of' 8 401 113 individuals received schistosomiasis examinations and 14 individuals were parasitologically diagnosed, decreased by 97.67% compared with 600 cases in 2016. It was estimated of 37 601 c:ases of schistosome infection, decreased by 30.95% compared with 54 454 cases in 2016. One acute schistosomiasis case was reported in 2017. There were 29 407 advanced schistosomiasis cases documented in 2017. Oncomelania hupensis snail surveys were performed in 19 784 endemic. villages and O. hupensis snails were found in 7 310 villages, accounting for 36.95% of' total villages, with 19 newly detected villages with snails. The snail survey covered an area of 622 454.49 hm2 and snails were found in an area of 172 501.56 hm2, including a newly detected area of 208.54 hm2. No schistosome-infected snails were found in 2017. A total of 737 016 bovines were raised in the schistosomiasis endemic, areas. Of them, 454 830 bovines received the examinations for schistosome infection, and 1 bovine was stool examination positive. There were 119 326 schistosomiasis cases receiving chemotherapy in 2017, with 1 973 968 individuals undergoing expanded chemotherapy; one bovine with schistosomiasis receiving chemotherapy, with 418 925 bovines undergoing expanded chemotherapy. A total of 144 605.31 hm2 area with snail was controlled by using molluscicides, with actual molluscicide-treated area of 73 755.37 hm2; and 5 002.92 hm2 area with snail was treated by environ-mental modification. Based on the data from the 457 national schistosomiasis surveillance sites , the mean ,Schistosoma japonicum infection rate was 0.001 6% and 0 in humans and bovines , respectively. No schistosome-infected snails were found by microscopic, examinations in all the surveillance sites , and 7 snail samples with schistosome nucleic, acid positive were detected by loop-mediated isothermal amplification (LAMP) among 6 surveillance sites. The results demonstrate a continuous decline trend on the endemic. Situation of schistosomiasis in P. R. China. However, the risk of epidemic, rebound still exists in some regions and it is still a challenge to achieve the target set by the Thirteenth Five-Year National Plan for Schistosomiasis Control in 2020.