Successful outcome of an integrated strategy for the reduction of schistosomiasis transmission in an endemically complex area

Abstract

Abstract. Schistosomiasis is one of the major public health problems in the People's Republic of China (and elsewhere), seriously threatening health as well as social and economic development. An integrated control strategy, emphasising transmission control but also aimed at reducing greenhouse gases, was carried out in Jiangling county, Hubei province from 2007 to 2009. Three villages were chosen for a pilot study involving removal of cattle from neighbouring, snail-infested grasslands, improving sanitation and construction of units for household biogas production in addition to routine control measures. Both prevalence and intensity of infection in the snails in the neighbourhood were greatly reduced after two years of implementation, while the prevalence of schistosomiasis in humans in the three villages had been reduced by 29%, 34% and 24%, respectively. The removal of cattle and construction of biogas production units had an additional positive effect in that the annual, average emission of greenhouse gases such as methane (CH 4 ) and carbon dioxide (CO 2 ) were reduced by an estimated 7.8 and 80.2 tons, respectively.

Pattern analysis of schistosomiasis prevalence by exploring predictive modeling in Jiangling County, Hubei Province, P.R. China

“…The decades’ efforts has led to remarkable progress on the control and prevention of this disease [9, 24]. However, in current stage of lower infection rate the potential risks of direction infection still exist in certain regions, especially in the marshland and/or lake regions [25].…”

Reduction Patterns of Acute Schistosomiasis in the People's Republic of China

“…Briefly, the acute case is considered due to the patient who has: (i) history of water contact in the endemic areas of schistosomiasis from last four weeks to three months, (ii) symptoms of fever, hepatomegaly and peripheral eosinophilia, and (iii) schistosoma eggs found from faeces. Outbreaks are determined in accordance with the criteria of Response and Management Scheme for Schistosomiasis Outbreaks [8] and confirmed by experts from the National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention [24]. An imported case of acute schistosomiasis is recorded when confirmed to have been infected outside the reported region, e.g.…”

“…The current strategy is focused on control of infection sources, a shift from the earlier strategy of morbidity control [5], [6], in order to strengthen the implementation of integrated measures aiming to reduce the transmission of S. japonicum from cattle and humans to snails [7]. The control strategy includes the following main interventions: (i) replacement of bovines and most water buffalo by tractors for agricultural activities [8]; (ii) rearing livestock in pens and forbidding them to pasture in marshlands where snail habitats exists [9]; (iii) recycling excreta from humans and domestic animals to produce methane for cooking [10]; (iv) requiring fishermen to use containers to prevent excreta from being released into the water in Poyang Lake and Yangtze River area [11], (v) improving the environment in high risk areas [12]; and (vi) implementing other routine health-control measures, such as snail survey and elimination, regular surveys and treatments, and health education [13], [14]. This work plan has been boosted by joint efforts from both the central and local governments to produce an effective control program.…”

Schistosomiasis japonica: Modelling as a tool to explore transmission patterns

“…The water buffalo plays a more important role, accounting for more than 75%, of all transmission, which is much more than the role played by humans supporting the notion that the human-snail-human cycle is currently relatively minor, at least in the lake regions (Williams et al, 2002). Second, control strategies varies also with prevalence levels, environmental settings, target populations and so on Hu et al, 2010;Li et al, 2012;Liang et al, 2002;Zhou et al, 2011).…”

“…The reason is that it: (i) answers truth/false questions when research hypotheses are tested, such as evaluating sensibility and specificity of various diagnostic approaches (Wang et al, 2006); (ii) estimates unknown parameters more accurately, such as some of the variables used in mathematical models for reducing the uncertainty (Liang et al, 2005); and (iii) is flexible, not only easy to apply and analyse, but also to understand complicated phenomena, particularly data with spatial and temporal attributes (Yang et al, 2005). Mathematical models are particularly useful for the study of transmission dynamics: (i) simulating the dynamical process of schistosomiasis transmission (Gray et al, 2008); (ii) calculating the transmission threshold of schistosomiasis (Zhuo et al, 1990); and (iii) evaluating, comparing, optimizing control strategies through transmission simulation (Hu et al, 2010;Li et al, 2012;Yang et al, 2005).…”