Endemic Situation Of Schistosomiasis Research Articles

Endemic situation of schistosomiasis in Suzhou City from 2010 to 2020

To analyze the endemic status of schistosomiasis in Suzhou City from 2010 to 2020, so as to provide the evidence for formulating the future schistosomiasis control strategy. The data pertaining to the endemic status of schistosomiasis in Suzhou City from 2010 to 2020 were retrieved from the annual schistosomiasis control report, the information management platform of schistosomiasis (parasitic diseases) in Jiangsu Province and the Parasitic Diseases Control Information Management System of Chinese Center for Disease Control and Prevention, including snail survey data, snail control data and schistosomiasis examination data, and were retrospectively reviewed. Differences of proportions were tested for statistical significance with chi-square test, and the trends in proportions were evaluated using the chi-square test for trends. Elimination of schistosomiasis was achieved in Suzhou City in 2018, and there were 3.528 9 million residents living in schistosomiasis-endemic villages of 81 townships in 9 counties. A total of 707 600 labor-days were used for snail survey in 11 586 village-times in Suzhou City from 2010 to 2020, covering 18 572.73 hm2, and snail habitats were detected with an area of 68.61 hm2, including emerging snail habitats of 37.30 hm2. A total of 23 144 snails were dissected, and no Schistosoma japonicum infection was detected. Reemerging and emerging snail habitats were predominantly found in inlands. During the period from 2010 to 2020, snail control was performed in Suzhou City for 71 000 labor-times, and snail control was done covering 269.34 hm2 through chemical treatment and covering 3.48 hm2 through environmental improvements. A total of 674 002 person-times received serological tests for S. japonicum infections in Suzhou City from 2010 to 2020, with seroprevalence of 0.38%, and a total of 33 835 person-times received stool examinations, with no egg-positives identified. The sero-prevalence of S. japonicum infections appeared an overall tendency towards a rise in Suzhou City from 2010 to 2020 (χ2 = 129.48, P < 0.001). The sero-prevalence of S. japonicum infections appeared high among local residents in 2016, and remained stable in other years, while the sero-prevalence of S. japonicum infections appeared an overall tendency towards a rise among mobile populations (χ2 = 54.11, P < 0.001). There were 278 800 and 175 202 serological tests among local residents and mobile populations in Suzhou City from 2013 to 2020, and 0.50% and 0.35% sero-prevalence rates were detected, respectively. The sero-prevalence of S. japonicum infections was significantly higher among local residents than among mobile populations in Suzhou City (χ2= 54.76, P < 0.001). There is a risk of rebound of schistosomiasis in Suzhou City. Integrated control should be reinforced to prevent the risk of rebound of schistosomiasis in Suzhou City.

Opportunities and challenges of schistosomiasis control during the construction of the Chengdu-Chongqing economic circle

Chengdu-Chongqing economic circle is centered on Chengdu City and Chongqing Municipality, with aims to build the "fourth growth pole" of China's economy. During this circle, elimination of schistosomiasis had been achieved in 82.5% of the endemic counties (districts) of Sichuan Province, and schistosomiasis is not historically endemic in Chongqing Municipality; however, there is still a risk of schistosmiasis transmission in Sichuan Province and Chongqing Municipality because the natural and social factors affecting schistosomiasis transmission have not been completely eliminated in these areas. Based on the endemic situation of schistosomiasis in Sichuan Province and Chongqing Municipality, we analyzed the opportunities and challenges of schistosomiasis control during the construction of Chengdu-Chongqing economic circle, and proposed the corresponding suggestions, so as to provide insights into the sustainable development of schistosomiasis control in the context of the Chengdu-Chongqing economic circle construction.

Endemic situation of schistosomiasis in national surveillance sites of Zhejiang Province from 2015 to 2019

To analyze the endemic situation of schistosomiasis in national surveillance sites of Zhejiang Province, so as to provide the scientific evidence for formulating the new schistosomiasis surveillance program and consolidating schistosomiasis elimination achievements. A total of 54 to 55 national surveillance sites and 6 risk monitoring sites were assigned in historical endemic regions of Zhejiang Province from 2015 to 2019, where the Schistosoma japonicum infections in humans, livestock, snails and wild feces were monitored. All data pertaining to the surveillance results were descriptively analyzed. There were 34 530 person-time local residents receiving serological screening for S. japonicum infections in national surveillance sites of Zhejiang Province from 2015 to 2019, and the seroprevalance of S. japonicum infections were 0.29% to 0.68%; however, no egg-positives were detected. During the period from 2015 to 2019, there were 62 086 person-time mobile populations receiving serological screening for S. japonicum infections in national surveillance sites of Zhejiang Province, and the seroprevalance of S. japonicum infections were 0.32% to 0.56%; additionally, there were 27 egg-positives identified, including 3 imported cases with schistosomiasis haematobia and one case with acute schistosomiasis japonica, indicating that the adjusted prevalence of Schistosoma infections were 0.01% to 0.07% among mobile populations. A total of 829 livestock were examined for S. japonicum infections, with no positives detected. There were 10.55 hm2 and 2.89 hm2 snail habitats found in national surveillance sites and risk monitoring sites of Zhejiang Province during the 5-year period, respectively; however, no S. japonicum infections were identified in snails. Moreover, a total of 305 wild feces were tested for S. japonicum infections, and no egg-positives were identified. The schistosomiasis elimination achievement have been consolidated in Zhejiang Province; however, the risk factors of re-emerging schistosomiasis have not been completely eliminated, such as residual snails and imported schistosomiasis cases. Further surveillance and control activities of snails and the source of S. japonicum infections should be reinforced.

Endemic situation of schistosomiasis in national surveillance sites of Hubei Province from 2015 to 2019

To analyze the changing tendency in the endemic situation of schistosomiasis in the national surveillance sites of Hubei Province, so as to provide the scientific evidence for facilitating the progress towards the elimination of schistosomiasis in the province. According to the National Schistosomiasis Surveillance Scheme (2014 version), a total of 65 national schistosomiasis surveillance sites were assigned in Hubei Province, and the Schistosoma japonicum infections in humans, domestic animals, snails and wild feces were monitored in these national surveillance sites from 2015 to 2019. All data pertaining to the surveillance results were descriptively analyzed. There were 151 159 person-time local residents and 70 928 person-time mobile populations screened for S. japonicum infections in the 65 national surveillance sites of Hubei Province from 2015 to 2019, and the seroprevalance of S. japonicum infections reduced from 3.45% (1 077/31 197) in 2015 to 1.57% (431/27 371) in 2019 among local residents and from 1.06% (98/9 249) in 2015 to 0.81% (116/14 318) in 2019 among mobile populations. During the period from 2015 through 2019, there were 22 egg-positive local residents and 2 egg-positive mobile populations identified in 2015, with 0.07% and 0.02% prevalence rates of S. japonicum infections, respectively. During the 5-year period, a total of 7 025 herd-time domestic animals examined for S. japonicum infections, with no infections detected, and a total of 2 035 wild feces were tested, with no egg-positives identified in the 65 national surveillance sites of Hubei Province. Snail survey was conducted covering 28 767.35 hm2 during the 5-year period, and the area of snail habitats ranged from 1 609.82 to 2 119.81 hm2. The mean density of living snails and occurrence of frames with snails reduced from 0.360 5 snails/0.1 m2 and 11.26% in 2015 to 0.175 9 snails/0.1 m2 and 8.43% in 2019, respectively, and no S. japonicum infection was found in snails during the 5-year period. In addition, no snails were found in the potential schistosomiasis transmission foci in the two national surveillance sites in the Three Gorges Dam. The overall endemic situation of schistosomiasis appears a tendency towards a decline in Hubei Province during the period from 2015 through 2019; however, the schistosomiasis transmission risk remains. Improving the surveillance system of schistosomiasis and increasing the sensitivity and performance of the surveillance system are required to provide insights into the implementation of precision control strategy and interventions in Hubei Province.

Endemic situation of schistosomiasis in national surveillance sites of Zhenjiang City from 2015 to 2019

To analyze the endemic situation of schistosomiasis in national surveillance sites of Zhenjiang City from 2015 to 2019, so as to provide the scientific basis for the consolidation of schistosomiasis control achievements and timely treatment of risk factors. A total of 7 national schistosomiasis surveillance sites were assigned in Zhenjiang City from 2015 to 2019. According to the National Scheme for Schistosomiasis Surveillance (2014 version), Schistosoma japonicum infections were monitored in local residents, floating populations and livestock, and snail habitats were surveyed in Zhenjiang City from 2015 to 2019. The results of schistosomaisis surveillance in Zhenjiang City from 2015 to 2019 were analyzed. There were 15 848 and 7 779 person-times of local residents and floating populations receiving serological screening of schistosomiasis in 7 national surveillance sites of Zhenjiang City from 2015 to 2019, and the seroprevalence rates were 0.95% to 1.75% and 0.14% to 0.91% among local residents and floating populations, respectively; however, no egg-positives were identified. A total of 1 885 herd-times of livestock were detected, and no egg-positives were found. During the 5-year period, snail survey was conducted in snail habitats and suspected snail habitats covering 3 333.79 hm2, and there were 108.71 hm2 snail habitats identified, including 50.97 hm2 re-emerging snail habitats. The density of living snails was 0.007 to 0.125 snails/0.1 m2 from 2015 to 2019, which showed a trend for a rise year by year (χ2 = 2 732.626, P < 0.01); however, no S. japonicum infections were detected in snails. The endemic situation of schistosomiasis has been maintained at a low level in Zhenjiang City, and schistosomiasis control achievements are consolidated. However, snails are widely distributed in the city, and there are still risk factors associated with schistosomiasis transmission. Further integrated interventions require to be reinforced to timely manage the risk of transmission of schistosomiasis and promote the progress towards elimination of schistosomiasis.

Endemic situation of schistosomiasis in national surveillance sites of Hunan Province from 2015 to 2019

To analyze the changes in the endemic situation of schistosomiasis in national surveillance sites of Hunan Province, so as to provide scientific basis for the development of the schistosomiasis elimination programme in the province. According to the requirements of the National Guidelines for Schistosomiasis Surveillance in China (2014 version), a total of 41 national schistosomiasis surveillance sites were assigned in all disease-endemic counties (districts) across Hunan Province. During the period between 2015 and 2019, Schistosoma japonicum infections were monitored in local residents, mobile populations and livestock, and snail status was monitored. The morbidity due to schistosomiasis and snail status was compared between years. The sero-prevalence of S. japonicum infections was 2.57% and 1.56% in local residents and mobile populations in national surveillance sites of Hunan Province from 2015 to 2019, respectively, and the sero-prevalence appeared a tendency towards a decline over years. A higher sero-prevalence rate of S. japonicum infections was seen in men than in women (P < 0.01). During the 5-year study period, the sero-prevalence rate of human S. japonicum infections appeared a tendency towards a decline in the marshland, embankment, inner embankment and hilly types of endemic areas over years. There were 44 and 19 egg -positives detected in local residents and 5 and 1 egg-positives in mobile populations in 2015 and 2016 respectively. A total of 9 346 domestic animals were monitored from 2015 to 2019, and 6 egg-positives were detected in 2015 and 2016 (all were bovine). A total of 0.155 billion m2 settings were surveyed from 2015 to 2019, and the mean density of living snails appeared a tendency towards a decline over years, with a 45.79% reduction in 2019 as compared to 2015. However, no S. japonicum infections were identified in snails during the 5-year period. A total of 1 469 mixed snail samples were detected using loop-mediated isothermal amplification (LAMP), and 6 positive snail samples were identified in 2015 (one sample) and 2017 (5 samples). The overall endemic situation of schistosomiasis appears a tendency towards a decline in Hunan Province, and the prevalence of S. japonicum infections is at a low level in humans and livestock; however, there is still a risk of schistosomiasis transmission. Improvements of health education, intensification of schistosomiasis examinations in mobile populations and reinforcement of the surveillance-response system is required to consolidate the achievements of schistosomiasis control in Hunan Province.

Endemic situation of schistosomiasis in national surveillance sites of Anhui Province from 2015 to 2018

To analyze the endemic situation of schistosomiasis in national surveillance sites of Anhui Province from 2015 to 2018, so as to provide scientific evidence for schistosomiasis control and prevention in Anhui Province. According to the National Schistosomiasis Surveillance Programme (2014 version), a total of 51 national schistosomiasis surveillance sites were assigned in Anhui Province in 2015, and Schistosoma japonicum infections in humans and livestock and snail distribution were monitored from 2015 to 2018. A total of 89 638 local residents and 42 609 mobile populations received serological screening of schistosomiasis in 51 national surveillance sites of Anhui Province from 2015 to 2018, and the sero-prevalence of S. japonicum infections was 1.41% to 3.69% in local residents and 0.84% to 2.13% in mobile populations, respectively. There were 5 egg-positive local residents and 1 egg-positive mobile populations detected in 2015, with occupations of farmers and fishermen. There were 6 405 livestock detected for S. japonicum infections, and no egg-positives were identified. Among an area of 12 661 hm2 surveyed in the national schistosomiasis surveillance sites of Anhui Province from 2015 to 2018, the areas of snail habitats were 2 461.27 to 2 628.96 hm2, andthemeandensityoflivingsnailswas 0.3757 to 0.4330 snails/0.1 m2, with no S. japonicum infections identified in snails. The endemic situation of schistosomiasis is at a low level in Anhui Province; however, the risk of schistosomiasis transmission remains in local regions of the province. The construction of the surveillance-responsesystemshouldbereinforcedtoconsolidatetheachievementsofschistosomiasis control in Anhui Province.

Endemic situation of schistosomiasis in Hunan Province in 2019

To analyze the endemic situation of schistosomiasis in Hunan Province in 2019, so as to provide insights into the achievement of transmission interruption of schistosomiasis in the province in 2020. The data pertaining to Schistosoma japonicum infections in humans and livestock and snail status were captured from Hunan Province in 2019 and analyzed. Schistosomiasis was endemic in 281 townships (towns) from 41 counties (districts) of 6 cities in Hunan Province by the end of 2019. A total of 991 900 persons received blood testing in Hunan Province in 2019, and 22 773 were positive for the blood testing, with sero-prevalence of 2.30%. All stool examinations were negative in 22 933 individuals detected. The high sero-prevalence was seen in Nanxian County, Anxiang County and Ziyang District. Currently, there were 5 034 cases with advanced schistosomiasis detected in Hunan Province, and they were predominantly identified in Yuanjiang City, Heshan District and Yueyang County. There were 44 963 bovines fenced in schistosomiasis-endemic villages in Hunan Province in 2019, which were predominantly distributed in Yuanjiang City, Hanshou County and Ziyang District, and no positives were detected in 1 996 bovines receiving blood testing or 20 684 bovines receiving stool examinations. In 2019, there were snail habitats of 1.73 billion m2 found in Hunan Province, which were mainly found in Yuanjiang City, Hanshou County and Yueyang County. The endemic situation of schistosomiasis further decreases in Hunan Province in 2019; however, there is still a risk of schistosomiasis transmission in local areas of the province.

Endemic situation of schistosomiasis in surveillance sites of Tianmen City from 2015 to 2018

To monitor the change patterns of the endemic situation of schistosomiasis in Tianmen City from 2015 to 2018, so as to provide the evidence for formulating the schistosomiasis control strategy in the city. A total of 8 schistosomiasis surveillance sites were assigned in Tianmen City from 2015 to 2018, and the endemic situation of schistosomiasis and the related epidemiological factors were monitored. During the period from 2015 to 2018, a total of 15 983 local person-times and 3 629 mobile populations were detected for schistosomiasis using an indirect hemagglutination test (IHA) in Tianmen City, and the sero-prevalence was 0.88% to 1.44% and 0.96% to 2.39%, respectively; however, no egg-positives were identified. A total of 1 245 herd-times were detected, and no egg-positives were found in bovines. In addition, the areas of snail habitats were 116.69 to 117.23 hm2 and the mean densities of living snails were 0.07 to 0.17 snails/0.1 m2 during the study period; however, no infections were identified in snails. The endemic situation of schistosomiasis appears low in Tianmen City; however, the factors related to schistosomiasis transmission remain in the city. The integrated strategy with emphasis on the control of infectious sources should be still intensified to consolidate the schistosomiasis control achievements.

Endemic status of schistosomiasis in People's Republic of China in 2018

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.

Endemic situation of schistosomiasis in national surveillance sites of Jiangsu Province from 2011 to 2018

To analyze and investigate the changing trend of the endemic situation of schistosomiasis in national surveillance sites of Jiangsu Province from 2011 to 2018, so as to provide scientific evidence for formulating strategies for schistosomiasis control. From 2011 to 2014, the national schistosomiasis surveillance sites were set in seven schistosomiasis endemic counties (cities, districts) across Jiangsu Province as according to the National Schistosomiasis Surveillance Scheme (2011 version), and from 2015 to 2018, the national surveillance sites were assigned in all 64 counties (cities, districts) endemic for schistosomiasis in Jiangsu Province according to the National Schistosomiasis Surveillance Scheme (2014 version). Schistosoma japonicum infections in local populations, mobile populations and livestock, and snail status were monitored in the national schistosomiasis surveillance sites of Jiangsu Province from 2011 to 2018, and the monitoring data were statistically analyzed. The sero-prevalence of S. japonicum infections was 1.50% to 4.61% among local populations in the national schistosomiasis surveillance sites of Jiangsu Province from 2011 to 2018, and a higher sero-prevalence was seen in men than in women, with the sero-positives predominantly detected in local populations at ages of over 50 years. The positive rate of stool examinations was 0 to 0.14% among sero-positive local populations in the national schistosomiasis surveillance sites of Jiangsu Province from 2011 to 2018, and no acute case was found in local populations during the study period. The sero-prevalence of S. japonicum infections was 0.46% to 15.97% among mobile populations in the national schistosomiasis surveillance sites of Jiangsu Province from 2011 to 2018, and no egg-positives were identified. A total of 1 453 livestock were tested in the national schistosomiasis surveillance sites of Jiangsu Province from 2011 to 2018, and no S. japonicum infections were detected. During the period from 2011 through 2018, snail survey was conducted in an area of 216 million m2 in the national schistosomiasis surveillance sites of Jiangsu Province, and 1 291.01 hm2 snail habitats were identified, with snail densities ranging from 0.01 to 0.47 snails/0.1 m2; however, no S. japonicum infections were identified in snails. The overall endemic situation of schistosomiasis appears a tendency towards a decline in Jiangsu Province, and S. japonicum infection remains at a low level in both humans and livestock. No S. japonicum infection has been identified in local populations in Jiangsu Province since 2012. In the future, monitoring and management of imported sources of S. japonicum infections should be intensified in Jiangsu Province, and the capability building of passive surveillance of schistosomiasis should be improved in sentinel hospitals in national schistosomiasis surveillance sites of Jiangsu Province. In addition, the examination of schistosomiasis should be strengthened in mobile populations in Jiangsu Province, a sensitive and effective surveillance-response system for schistosomiasis is urgently needed.

Endemic situation of schistosomiasis in Wuhu City from 2009 to 2018

To analyze the endemic situation of schistosomiasis in Wuhu City from 2009 to 2018, so as to provide evidence for adjusting and developing the control strategy. The data regarding the endemic situation were retrospectively collected and analyzed in Wuhu City from 2009 to 2018. The prevalence of human Schistosoma japonicum infections reduced from 0.450% in 2009 to 0.035% in 2018 in Wuhu City, and a reduction rate of 92.22% (χ2 = 1 6128.307, P < 0.01), and the prevalence of S. japonicum infections decreased from 0.483% in 2009 to 0 in 2018 (χ2 = 27.570, P < 0.01) in livestock. The area of snail habitats increased from 1 501.07 hm2 in 2009 to 4 408.62 hm2 in 2018, with an increase of 193.70%. No infected snails were found in Wuhu City since 2012, and no egg positives were detected in humans and livestock since 2016. Currently, the endemic situation of schistosomiasis is at a low level in Wuhu City; however, there are still factors affecting schistosomiasis transmission. In the future, the integrated strategy with emphasis on the control of infectious source and the surveillance-response system should be intensified to consolidate the achievements of schistosomiasis control.

Endemic situation of schistosomiasis in Jiangshan City from 2008 to 2018

To analyze the endemic situation of schistosomiasis in Jiangshan City from 2008 to 2018, so as to provide evidence for formulating the future control strategy. The data regarding Oncomelania snail survey and control, schistosomiasis examinations and environmental improvements were collected in Jiangshan City from 2008 to 2018. The changes in snail status and morbidity due to Schistosoma japonicum infections were analyzed to assess the effectiveness of comprehensive schistosomiasis control. From 2008 to 2018, a total of 61 220 person-times were examined for S. japonicum infections in Jiangshan City, and the overall seroprevalence of S. japonicum infections was 0.56% (343/61 220); however, no egg-positives were detected. Among 4 231 cattle screened for S. japonicum infections using blood tests in Jiangshan City during the period from 2008 to 2018, 12 were sero-positive, with sero-prevalence of 0.28% (12/4 231), and no egg-positives were identified. There were 422 snail habitats identified in Jiangshan City during the study period, covering an area of 46.915 hm2, and among the 31 686 snails dissected, no S. japonicum infections were detected. An area of 3 625.492 hm2 snail habitats were subjected to repeated snail control and 11 settings were given environmental improvements, covering snail habitats of 17.880 hm2 and historical snail habitats of 204.380 hm2. Following the implementation of environmental improvements-based comprehensive schistosomiasis control, the endemic situation of schistosomiasis is stable in Jiangshan City; however, there is still a risk of snail importation and re-emerging schistosomiasis. Therefore, the monitoring of snails and morbidity due to S. japonicum infections should be intensified in the city.

Endemic situation of schistosomiasis in People's Republic of China from 2010 to 2017

To understand the epidemic trend of schistosomiasis in China from 2010 to 2017 so as to provide the scientific evidence for schistosomiasis elimination. 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. 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. 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.

Thinking on schistosomiasis control under the strategy of China's Yangtze River Economic Belt

The construction of Yangtze River Economic Belt has been included in the national strategy of China, aiming to improve the economic level of the whole population, and to build a green ecological corridor with the joint development of economy, balance, ecology and equity. Yangtze River Economic Belt is the main area where schistosomiasis is endemic. During the economic construction, the prevention and control of schistosomiasis should be strictly carried out to facilitate the progress towards schistosomiasis elimination in China. In this paper, the endemic situation of schistosomiasis in Yangtze River Economic Belt areas and the possible impact on the schistosomiasis control were analyzed. In addition, a few suggestions were proposed for schistosomiasis control in Yangtze River Economic Belt areas.

Main challenges and strategy of schistosomiasis control in mountainous and hilly regions of China

This review describes the epidemic characteristics and endemic situation of schistosomiasis in mountainous and hilly regions of China, analyzes the main challenges of schistosomiasis control in mountainous and hilly regions and proposes targeted suggestions for the future schistosomiasis control, with aims to accelerate the progress towards schistosomiasis elimination in mountainous and hilly regions and facilitate the achievement of the goal set in The Thirteenth Five-Year National Plan for Schistosomiasis Control in China and The Three-year Tough Action Plan for Endemic Diseases Control (2018-2020) in China.

Development and model of health education and health promotion for schistosomiasis control in mountainous and hilly endemic areas

Transmission control and interruption of schistosomiasis has been gradually achieved in the mountainous and hilly endemic areas with the implementation of the schistosomiasis control programmes, which are moving towards the progress of schistosomiasis elimination. As an important measure of schistosomiasis control, health education is experiencing new challenges and problems in the new situation, and conventional health education of schistosomiasis control has already failed to meet the needs of socioeconomic and cultural development and the increasing changes of human production and life styles in the endemic areas. Therefore, a precision health education model for schistosomiasis control is of great need to be established to highly effectively promote the implementation of schistosomiasis control measures. This review summarizes the important role of health education in schistosomiasis control in mountainous and hilly endemic areas, and describes the new health education model based on optimization of the policy environment and creation of the community atmosphere according to the changes in the endemic situation of schistosomiasis and requirements of the schistosomiasis control target, so as to promote the precision and sustainable implementation of health education and health promotion in schistosomiasis control.

Effect of integrated schistosomiasis control in Honghu City from 2008 to 2018

To evaluate the effect of integrated schistosomiasis control measures in Honghu City during the period from 2008 through 2018. The data pertaining to schistosomiasis control measures and the endemic situation of schistosomiasis in Honghu City were collected from 2008 to 2018, and the effect of integrated schistosomiasis control measures implemented was evaluated. The resources from agriculture, water resources, forestry, land, education and communication sectors were integrated to implement the integrated schistosomiasis control strategy with the focus on the control of source of Schistosoma japonicum infection in Honghu City from 2008 to 2018. The prevalence of S. japonicum infection reduced from 3.03% in 2008 to 0 in 2018 in humans in the city, and no acute infection was detected since 2009. In addition, the prevalence of S. japonicum infection in cattle reduced from 2.85% in 2008 to 0 in 2018, and no snail infection was found since 2012. Transmission control of schistosomiasis was achieved in the city in 2013, and transmission interruption was achieved in 2018. The integrated schistosomiasis control measures achieve remarkable effects in Honghu City; however, there is still a risk of schistosomiasis transmission.

Endemic status of schistosomiasis in People's Republic of China in 2017

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.

Progress and challenges of schistosomiasis elimination in China

Schistosomiasis is an old and geographically widespread parasitic disease that severely damages human health and affects socioeconomic development in China. The implementation of the integrated strategy with emphasis on controlling the source of Schistosoma japonicum infection and the National Mid- and Long-Term Plan for Schistosomiasis Prevention and Control (2004-2015) in China greatly facilitated the progress towards the elimination of schistosomiasis in China. Since transmission control of schistosomiasis was achieved in 2015, the goal of the national schistosomiasis control program has moved to transmission interruption and elimination in China. Because of the impacts of natural and social factors, and the new situation, new task and new demands following the continuous decline in the endemic situation of schistosomiasis, several challenges exist to achieve the goal of schistosomiasis elimination nationwide. This paper analyzed the current endemic status of schistosomiasis, progress and challenges of schistosomiasis elimination, and proposed some suggestions for the national chistosomiasis elimination program in China.