Effect Of Schistosomiasis Control Research Articles

Effect of integrated schistosomiasis control measures in Hunan Province from 2004 to 2019

To examine the effect of the integrated schistosomiasis control measures in Hunan Province from 2004 to 2019, so as to provide insights into the development of the schistosomiasis elimination strategy. The integrated schistosomiasis control measures implemented by the health, agriculture, water resources, forestry, land and resources sectors were retrospectively collected in Hunan Province from 2004 to 2019, and the completion of each measure, cost of control measures, Schistosoma japonicum infections in humans and bovines, and snail status were analyzed each year. An index system for assessing the integrated schistosomiasis control effect was constructed using the Delphi method to calculate the integrated schistosomiasis control effect index. In addition, a cost-effect analysis was performed in terms of the decline in the prevalence of S. japonicum infections in humans and bovines, areas with snails in inner embankments, and areas with infected snails. A total of 7 110 926 500 Yuan were invested into the integrated schistosomiasis control program of Hunan Province from 2004 to 2019. During the 16-year period, a total of 277 437.12 hm2 snail habitats received molluscicidal treatments, 6 927 230 person-times given expanded chemotherapy, 2 116 247 bovine-times given expanded chemotherapy, 954 850 harmless toilets built, 290 359 bovines fenced, 136 666 bovines eliminated, 141 905 machines used to replace bovines, 39 048.63 hm2 water lands improved as dry lands, 724.12 km irrigation regions improved, 3 994 300 populations covered with safe water, 191 102.89 hm2 forests planted and 38 535.27 hm2 lands leveled. The prevalence of S. japonicum infections was 4.29% in humans and 4.48% in bovines in Hunan Province in 2004, with 2 449.37 hm2 snail habitats in inner embankments and 3 423.74 hm2 infected snail areas. In 2019, the prevalence of S. japonicum infections reduced to 0 in both humans and bovines, and areas of snail habitats reduced to 540.92 hm2 (77.92% reductions), while the areas with infected snails reduced to 0. The overall integrated schistosomiasis control effect index appeared a tendency towards a rise over years since 2004, and the integrated schistosomiasis control effect index was 97.35 in 2019; the annual mean costs for a 1% reduction in the prevalence of S. japonicum infections in 100 populations and 100 bovines were 70.11 Yuan and 4 204.78 Yuan, and the annual mean costs for a 1% reduction in the snail areas in inner embankments and infected snail areas were 2 010.20 Yuan and 1 298.09 Yuan, respectively. The integrated control measures achieve remarkable effectiveness for schistosomiasis control in Hunan Province, with a remarkable decline in the prevalence of S. japonicum infections in humans and bovines and great shrinking of snail areas in inner embankments and infected snail areas. Adequate fund investment is required to improve the integrated schistosomiasis control measures and consolidate the control achievements.

Schistosomiasis control effect in Mianyang City in ten years after Wenchuan earthquake

To evaluate the effect of schistosomiasis control in Mianyang City in ten years after Wenchuan earth-quake, so as to provide the experiences for schistosomiasis control post-disaster. The data of implementation of schistosomiasis control work in ten years after the Wenchuan earthquake were collected and analyzed for the epidemic situation of schistosomiasis in Mianyang City. Meanwhile, the awareness situation on schistosomiasis control of villagers and students was investigated by questionnaires in 2008 and 2015. All of the 6 counties (cities, districts) with schistosomiasis endemic in Mianyang City were hit by the earthquake disaster. After the disaster, the measurements including the conventional schistosomiasis control measures, the control of exogenous infection sources, the control of Oncomelania hupensis snails, and health education were carried out. The relevant departments of schistosomiasis control were cooperated to implement the prevention and control measures. The schistosomiasis prevalence of population and the snail condition rose in the year of the earthquake, but then declined year by year. In 2015, the awareness rates of schistosomiasis control of both villagers and the students were significantly improved compared with those in 2008. The measures of schistosomiasis control after the earthquake disaster are effective in Mianyang City, and the goal to prevent major plague after the earthquake is achieved.

Effect of schistosomiasis control in Yangxin County, Hubei Province, 2004-2015

To evaluate the effect of schistosomiasis control and prevention in Yangxin County from 2004 to 2015, so as to provide the evidence for improving the work of schistosomiasis transmission interrupted and elimination in the future. According to the endemic types and endemic regularity of schistosomiasis in Yangxin County, the comprehensive control strategies were adopted, and the programs related to sanitation, water conservancy, forestry, and agriculture were implemented continuously. The schistosomiasis control effects in this county from 2004 to 2015 were analyzed and compared. After the implementation of the schistosomiasis comprehensive control strategies in Yangxin County, the calculated number of patients reduced from 22 240 in 2004 to 1 471 in 2015, the infection rate of residents reduced from 8.57% in 2004 to 0.16% in 2015, the number of patients with acute schistosome infection reduced from 64 in 2004 to 0, and no cases of acute schistosomiasis found since 2009. The infection rate of cattle decreased from 8.87% in 2004 to 0. The area with Oncomelania hupensis snails and the area of susceptible zone reduced from 3 446.21 hm2 and 1 111.59 hm2 in 2004 to 2 285.75 hm2 and 41.28 hm2 in 2015 respectively, and the schistosome-infection rate of snails reduced from 0.76% in 2004 to 0. Since the comprehensive control strategy implemented from 2004, the endemic situation of schistosomiasis in Yangxin County has decreased significantly. However, the harness force of the Fu River as well as the control of infection source of livestock still should be strengthened to consolidate the control achievement.

Effect of comprehensive schistosomiasis control measures in Kaihua County from 1996 to 2015

To evaluate the control effect of comprehensive measures of schistosomiasis after its transmission interruption in Kaihua County, Zhejiang Province, so as to provide the references for further consolidation of schistosomiasis control. The data of Oncomelania hupensis snail survey and control, as well as environmental reform in Kaihua County were collected and analyzed from 1996 to 2015. From 1996 to 2015, totally 2 635 snail habitats and 102.75 hm2 area with snails were found, and 125.4 thousand snails were dissected and no one was schistosome infected. The accumulated snail control area was 4 932.98 hm2, and the area with snails was effectively reduced by the comprehensive control measures. The schistosomiasis control effect could be consolidated by the comprehensive control measures emphasizing environmental reconstruction, and the snail surveillance work still should be strengthened.

Surveillance on schistosomiasis after its transmission interruption in Baoying County, Jiangsu Province

To understand the endemic situation of schistosomiasis after its transmission interruption in Baoying County, so as to provide the evidence for adjusting the prevention and control strategy. The data of schistosomiasis surveillance in Baoying County from 1988 to 2015 were collected and retrospectively analyzed. The schistosomiasis surveillance has been established since it was interrupted in Baoying County in 1987. The total surveyed area with Oncomelania hupensis snails was 21 269.95 hm2, but no living snails were found. The number of schistosomiasis examinations of residents was 163 196 person-times, and 270 person-times were positive in serum test, 26 person-times were positive in stool test. No positive cases were found since 1997. The number of schistosomiasis tests of livestock was 2 180 cattle-times but no infection was found. No schistosome infected snails or livestock are founded in Baoying County for last 28 years, and no patients are founded for last 11 years. The effect of schistosomiasis control is steady.

Emergency response and effect evaluation on schistosomiasis control in rescue of shipwreck event in Yangtze River

To evaluate the effect of schistosomiasis control in"Oriental Star shipwreck event"in Jianli County, Hubei Province, so as to provide experiences for schistosomiasis prevention and control in rescue of emergency in the future. According to the data of historical schistosomiasis prevalence and the results of the field survey in the townships in the upstream and downstream of the rescue spots, the emergency handling measures of schistosomiasis control were evaluated. Meanwhile, the Oncomelania hupensis snail situation, priority crowd chemotherapy, key aquatic monitoring, and illness monitoring of people and livestock were investigated to evaluate the schistosomiasis control effect after the events comprehensively. There were no schistosome-infected snails found in the place of shipwreck and the rescue spots. The average density of O. hupensis snails in 5 townships of Jianli County was 0.064 snails/0.1 m2, and there were no infected snails found. The positive rate of 2 090 migrants in the schistosomiasis serologic tests was 0.29% and there were no positive ones found in the fecal examination. There were no acute schistosomiasis cases found by the sentinel surveillance fever clinics, and also no positive cattle were found. The results of sentinel mice monitoring in the place of shipwreck and 4 villages in the upstream and downstream showed no infected mice were found. The schistosomiasis control measures taken after the shipwreck is effective, which achieves the goal of no schistosomiasis transmission after emergency.

Study on interventions based on systematic ecological system construction to interrupt transmission of schistosomiasis in hilly endemic regions

To study the effectiveness of comprehensive control measures based on systematic ecological system construction to interrupt the transmission of schistosomiasis in hilly endemic regions in Sichuan Province, so as to provide the evidence for adjustment of schistosomiasis prevention and control strategies. A high endemic area of schistosomiasis, Panao Township of Dongpo District in Meishan City, was selected as a demonstration area. The comprehensive measures for schistosomiasis control with focus on systematic ecological management were implemented, and the income of residents, indexes of schistosomiasis control effect and so on were investigated before and after the intervention and the results were compared. The project based on systematic ecological system construction started in 2009 and 317.351 million Yuan was put into the construction. The construction included economic forest plant base (1 866.68 hm2, 72.66% of the total farmland areas), ecological protection gardens (585.35 hm2) and so on. Totally 97.04% of historical areas with Oncomelania hupensis snails were comprehensively improved. In 2015, the peasants´ pure income per capita increased 4 938 Yuan, with the average annual growth rate of 14.69%. All the farm cattle were replaced by the machine. The benefit rate of water improvement was increased by 52.84% and the coverage rate of harmless toilets increased by 18.30%. The positive rate of serological tests for schistosomiasis decreased from 7.69% to 3.50%, and the positive rate of parasitological tests decreased from 1.18% to 0. The area with snails was decreased from 23.33 hm2 to 0. The awareness rate of schistosomiasis control knowledge and correct behavior rate of the residents increased from 85.50% and 82.60% to 95.70% and 93.90% respectively. The comprehensive schistosomiasis control measures based on systematic ecological management are conform to the currently actual schistosomiasis prevention and control work in hilly endemic regions, and have good ecological economic benefit and schistosomiasis control effectiveness, which provide an effectively new model of prevention and control for advancing process, consolidating the effect, finally realizing goal of interruption and elimination of schistosomiasis in hilly endemic regions.

Schistosomiasis control effect of agricultural integrated development in Tieban Marshland of Yangtze River

To evaluate the schistosomiasis control effect of the comprehensive measures that focused on beachland smoothing and tillage cultivation in Tieban Marshland, Wuhan Section of the Yangtze River. From 2011 to 2015, before and after the comprehensive control, the Oncomelania hupensis snail situations in Tieban Marshland were investigated in spring annually, and the residents aged 6-65 years in Huayuan Community which was next to the marshland were examined to understand their schistosome infection status. In late July, 2014, the sentinel mouse surveillance was carried out. Moreover, the economic effectiveness of comprehensive development was evaluated. The schistosome infection rates of residents in 2011 (before the comprehensive control), 2012 (after the comprehensive control), and 2013 were 0.72% (3/414), 0.37% (2/536) and 0.31% (1/326), respectively, and no schistosomiasis patients were found in 2014 and 2015. The snail area, the occurrence rate of frames with snails, and the average density of living snails in Tieban Marshland in 2005 decreased by 22.18%, 97.83% and 98.25%, respectively compared to those in 2011, and no schistosome infected snails were found. No positive mice were found in the sentinel mouse surveillance. The annual net income of Tieban Marshland increased by 233.33% compared to that before the comprehensive development. The endemic situation of schistosomiasis and snail situation declined significantly after the comprehensive development in Tieban Marshland, and the economic and social benefits are significant.

The effect and influencing factors of schistosomiasis control by forbidding livestock denaturing on marshland with Oncomelania snails

To evaluate the effect of schistosomiasis control by forbidding livestock denaturing on marshland with Oncomelania snails and to analyse its influencing factors. 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. 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. 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.