The Longitudinal Study On Endemic Situation Of Schistosomiasis And Cross-sectional Survey On The Quality Of Life Of Advanced Cases

PartⅠThe Longitudinal Study on Endemic Situation of Schistosomiasis in ChinaSchistosomiasis remains a major parasitic diseases causing serious damage to people's health and hindering the development of social economy.Schistosomiasis has long been endemic in China since at lease 21 years ago.According to the records in 1950s,11.6 million people suffered from schistosomiasis,1.2 million cattle infected, the total area of Oncomelania snail habitats was 14.3 billion m~2,and more than 100 million people were at risk of the infection,which distributed in 370 counties covering 10 provinces of Hunan,Hubei,Jiangxi,Anhui,Jiangsu,Zhejiang,Fujian, Guangdong,Yunnan,Sichuan,the municipality of Shanghai and the autonomous region of Guangxi,in the south China over the past 50 years.Led by the Party and the government,great progress has been made in schistosomiasis control in China.Since the 1980s,schistosomiasis control has been a hard task confronting China. Firstly,the prevalence increased considerably.Along with the natural disaster such as serious floods,global warming of weather,sharply increasing of migrant population and the transition of the commune system to a household responsibility system in the early 1980s,schistosomiasis control became more difficulty.Secondly,lack of funding for prevention and treatment was serious.Since 1980s,funds for schistosomiasis control reduced year by year,while the price of medicines and cost for medical treatment rose considerably,and control work was affected seriously. Thirdly,control of source of the infection was difficult and combined approaches for the control were very difficult to practice because of complicated environment of Oncomelania snail habitats in the lake regions and mountainous areas,and chemotherapy for man and domestic animals was no synchronous.Fourthly, institutions for schistosomiasis control and professionals could not meet the demands of control work.All in all,to control the endemicity of schistosomiasis and to roll back its rise in prevalence were a major public health problem in China by that time. So that,the government began to launch the 10 years' World Bank Loan Programme for Schistosomiais Control(WBLPSC) since 1992 to control Schistosomiasis in China.In term of endemic situation of schistosomiasis and the demands of WBLPSC,in order to follow up the endemicity and evaluate the effectiveness of WBLPSC,35 cohorts of schistosomiasis were set up in 1990,which represented the different eco-epidemiological settings and endemic levels were selected using multiple-stage cluster sampling method.The abundant results obtained from the annual cross-sectional surveys including data of annual human infection prevalence and infection intensity,the incidence of acute schistosomiasis and advanced cases,prevalence rate of animal reservoirs,snail density and snail infection rate.The database based on the above results helped the government to understand longitudinally how the schistosome-endemic situation changed over time.It was also helpful to evaluated whether control strategies were effective,to explore the related natural and social factors,to provide scientific proof to formulate and adopt anti-schistosomiasis policies.Along with the 15 years,250,000 person-years longitudinal study,following results were made:First,the number of highly endemic areas has been reduced significantly,which indicated that the control strategies of WBLPSC were effective.However,the fluctuations of the endemic situation in some pilots,support the notion that schistosomiasis is a long-term tasks.Second,while the infection rates among humans decreased significantly after implementation of control measures built around chemotherapy suggested by WBLPSC,it is hard to further decrease the rates,once the infection rate is below 5%. Thus,to consolidate control efforts and to further decrease prevalence rates among humans,other control measures are imperative,i.e.health education,chemotherapy of livestock and snail control by means of environmental management or mollusciciding.Third,the re-infection of schistosomiasis is a main problem for schistosomiasis control.It will be the new approaches to study the epidemiologic characteristics of re-infection and its risk factors such as environmental factors and genetic factors.Fourth,the infection rate of cattle was often at a high level.In the pilots schistosomiasis infection rates were well controlled after the cattle disappeared, underscoring their important role in transmission.Five,the snail situation varied considerably over time;in most cases,the densities of living snails and infected snails were high.Thus,there is need to emphasis snail control to monitor progress of interventions through suitable surveillance tools,especially in areas where transmission is under control.Six,the longitudinal study in transmission interrupted the areas indicated that the morbidity and snail were well controlled.However,with the increasing of mobile population,the imported cases may be the main problems in there areas.Thus,it is need to emphasis the surveillance on the persons who are from endemic areas of schistosomiasis. PartⅡCross-sectional Survey on the Quality of Life of Advanced Cases of SchistosomiasisQingpu district(county) of Shanghai was one of the ten most serious endemic counties of schistosomiasis in China.The number of cumulative advanced cases was 6014,which occupied thirty percent of total cases in Shanghai.Since the criteria of interruption of schistosomiasis reached in 1983,no new advanced case was found.To understand the survival status,the quality of life(QOL) of advanced cases of schistosomiasis,to analyze the it's possible factors on QOL and to explore the best ways to improve the QOL of these cases,three towns(Zhaoxiang,Chonggu and Xicen) was selected randomly as the study sites with the cluster sampling in Qingpu district.All the survival patients of advanced cases and some controls were interviews in these study sites with the constructed questionnaires to study the QOL and influencing factors.The main results were as follows:First,among the study population,more than 50%subjects were female and old residents.The ration of female to male was 247:100 and average age was 70.79±7.95. 73.30%of advanced cases were classified as splenomegaly,and 91.54%had operation history for splenectory among them.There were no significant differences between two groups(cases and controls) in the some basic living conditions,such as career, housing,type to drinking water,toilet and average income per month.We also did find any differences in the payment mode of medical expenditure,ratio of charges at user's own expenses,and health service needs.It was indicated that previous disease history of schistosomiasis has no more impact on the living status.Second,concerning the health status,56.55%of the survival patients with advanced schistosmiasis were afflicted with at least one type of disease.36.95%of cases suffered from more than two types of diseases.The first three kinds of diseases bases on prevalence were circulatory diseases,digestive diseases and respiratory disease.The survival patients with advanced schistosomiasis were in more serious condition that that of the controls on the anamnesis,inpatient times and medical expenses in the last year.Third,73.30%of patients reported that they can be involved in the normal activities,which was similar to the controls.However,16.92%of patients reported the capabilities of normal activities reduced.The differences with controls consisted of public vehicles,cooking,doing housework,eating,washing clothes,bathing,and shopping.87.83%of cases had at least on time of weekly physical activity,which was lee that of controls.Four,86.57%of advanced cases had a more than medium level(≥49) score of QOL.Evaluation by patient self was higher than that of controls according to WHOQOL-BREF.In the four components of WHOQOL-BREF,the score of physical, psychological,social relationship and environment above medium level(≥14) were 83.25%,92.54%,96.51%and 95.35%respectively.Compared with the controls,the score of QOL were lower in general,and the components of physical and psychological domain.Five,the multi-variables by Logistic regression indicated that appetite,physical activities,average income of family members per person,and gender were the positive factors on QOL.The negative factors were family contradiction,disease history in the past two weeks,economic supply and teeth lost.The most important factors were family contradiction,appetite and activity of daily living scale.