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Background: Schistosomiasis japonica remains an important public health concern due to its potential to cause severe outcomes and long-term sequelae. An integrated control strategy implemented in the Peoples' Republic of China has been shown to be effective to control or interrupt the transmission of schistosomiasis. The objective of this study is to estimate the disease burden of schistosomiasis and assess the cost-effectiveness of the integrated control strategy focused on different major interventions at three stages for schistosomiasis control in a lake setting, to provide reference for policy making or planning. Methods: Annual cost data of schistosomiasis control during 2009–2019 were obtained from the control program implementers in Jiangling County, Hubei Province, China. Economic costs are provided in constant 2009 Chinese Yuan (CNY). Epidemiological data of schistosomiasis were collected from the Jiangling county station for schistosomiasis control. Disease burden of schistosomiasis was assessed by calculating years of life lost (YLLs) owing to premature death, years lived with disability (YLDs) and disability-adjusted life years (DALYs). DALYs were calculated as the sum of YLLs and YLDs. We then conducted a rudimentary cost-effectiveness analysis by determining the ratio by dividing the difference between the average cost of integrated control strategy at transmission control (2013–2016) or transmission interruption (2017–2019) and the average cost at stage of infection control (2009–2012) with the difference between the DALYs of schistosomiasis at different control stages. Descriptive statistics on the costs and DALYs were used in the analysis. Results: The total economic costs for schistosomiasis control in Jiangling County from 2009 to 2019 were approximately CNY 606.88 million. The average annual economic costs for schistosomiasis prevention and control at stages of infection control (2009–2012), transmission control (2013–2016), and transmission interruption (2017–2019) were approximately CNY 41.98 million, CNY 90.19 million and CNY 26.06 million respectively. The overall disease burden caused by schistosomiasis presented a downward trend. Meanwhile, the disease burden of advanced cases showed an upward trend with the DALY increased from 943.72 to 1031.59 person-years. Most disease burden occurred in the age group over 45 years old (especially the elderly over 60 years old). Taking the infection control stage as the control, the incremental cost-effectiveness ratio of integrated control strategy was CNY 8505.5 per case averted, CNY 60 131.6 per DALY decreased at transmission control stage and CNY −2217.6 per case averted, CNY −18 116.0 per DALY decreased at transmission interruption stage. Conclusions: The disease burden of schistosomiasis decreased significantly with the implementation of the integrated prevention and control strategy. Surveillance and management on elder population should be strengthened to decrease diseases burden. There remains a need for well-conducted studies that examine the long-term cost-effectiveness of the integrated control strategy for schistosomiasis. Graphic Abstarct: [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A TLPB model for DCM removal was developed and agreed well with experimental data. • Monod model was used to obtain variation of biomass accumulation. • Effects of design parameters on performance were simulated. • A contour graph was used for CEA analysis under different conditions. Abstract Two-liquid phase biofilter (TLPB) is a new type biofiltration system for controlling hydrophobic volatile organic compounds. In this paper, a mathematical model was developed for a TLPB that can treat gaseous dichloromethane (DCM). The specific growth rate of the biomass inside the TLPB fitted the Monod model. u max and K s were 0.013 d−1 and 1.288 g m-3, respectively. The Henry's Law constant of the two liquid phase mixtures was obtained as 0.125 kPa m3 mol−1 under the addition of 10% silicone oil. Simulation results revealed that the model is a good tool for evaluating the removal performance of TLPB. Practical applications of the model indicated that an increase in the silicone-oil-to-mixture ratio and inoculated biomass improved the removal efficiency, whereas an increase in the inlet DCM concentration and gas velocity negatively affected the removal performance. Moreover, the model can be used to determine the design parameters and ensure that the outlet concentration satisfies the emission standards. The results of cost-effectiveness analysis indicated that the expenditure for DCM removal per year was low when TLPB was used to treat a high DCM concentration steam with a long empty-bed retention time. [ABSTRACT FROM AUTHOR]