Yoo Byung-Kwang, Iwamoto Ryo, Chung Ungil, Sasaki Tomoko, Szilagyi Peter G, Kitajima Masaaki
Faculty of Human Sciences, School of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa City, Saitama 359-1192, Japan; School of Health Innovation, Kanagawa University of Human Services, Research Gate Building TONOMACHI 2-A 2·3F, 3-25-10 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-0821, Japan.
SHIONOGI & Co., Ltd., 1-8, Doshomachi 3-chome, Chuo-ku, Osaka 541-0045, Japan; AdvanSentinel Inc., 1-8 Doshomachi 3-Chome, Chuo-ku, Osaka, Osaka 541-0045, Japan.
Sci Total Environ. 2025 Jun 18;990:179645. doi: 10.1016/j.scitotenv.2025.179645.
The COVID-19 pandemic continues to impose substantial burdens on vulnerable subpopulations such as long-term care facility (LTCF) residents. Our previous simulation study found that the economic efficiency of clinical screening tests (for asymptomatic individuals) at a single LTCF could be maximized if an optimal screening timing is triggered by city-level incidence. City-level incidence could be estimated by conventional "clinical surveillance" based on routine diagnostic tests for symptomatic patients visiting medical institutions. The current study's objective was to evaluate how the addition of "wastewater surveillance conducted at treatment plants (WSTPs)" to our hypothetical warning system (based on clinical surveillance as status quo) could improve the economic efficiency of clinical screening tests at "multiple LTCFs in a city" by recommending clinical screening tests to be initiated at LTCFs on a timelier basis. We performed cost-benefit analyses (CBAs), developing standard decision models with parameters assumed from the literature. CBAs' benefits included related health expenditure and quality-adjusted life-years (QALYs) saved, assuming a $35,234 (¥5 million)-per-QALY willingness-to-pay threshold. CBAs estimated return-on-investment (ROI, equivalent to benefit-to-cost ratio) and net-benefits (in 2024 US dollars) of our warning system at a single LTCF and at city and national levels in Japan, implementing clinical screening tests for all residents and staff members at LTCFs (N = 160-0.27 million). Our simulation results indicated that the addition of WSTPs is highly likely to generate incremental net-benefit of the proposed warning system, e.g., $172,000 at a single LTCF and $3.5-$41 million at the national level, during four weeks with a high incidence of COVID-19 infection. Estimates of ROI and net-benefits were generally robust, although it should be noted that they were sensitive to incidence and LTCFs' compliance to a warning. In conclusion, these findings specify the potential benefit of our proposed city-level warning system, generating net-benefit when combined with WSTPs for COVID-19.
新冠疫情继续给长期护理机构（LTCF）居民等弱势群体带来沉重负担。我们之前的模拟研究发现，如果根据城市层面的发病率触发最佳筛查时机，那么单个长期护理机构中临床筛查检测（针对无症状个体）的经济效率可以最大化。城市层面的发病率可以通过基于对到医疗机构就诊的有症状患者进行常规诊断检测的传统“临床监测”来估计。本研究的目的是评估在我们的假设预警系统（以现状的临床监测为基础）中加入“污水处理厂进行的废水监测（WSTP）”，如何通过更及时地向长期护理机构推荐临床筛查检测，来提高“城市中多个长期护理机构”临床筛查检测的经济效率。我们进行了成本效益分析（CBA），利用从文献中假设的参数建立了标准决策模型。CBA的益处包括节省的相关医疗支出和质量调整生命年（QALY），假设每QALY的支付意愿阈值为35,234美元（500万日元）。CBA估计了我们的预警系统在日本单个长期护理机构以及城市和国家层面的投资回报率（ROI，等同于效益成本比）和净效益（以2024年美元计），对长期护理机构的所有居民和工作人员进行临床筛查检测（N = 160 - 27万）。我们的模拟结果表明，在新冠病毒感染高发的四周内，加入污水处理厂废水监测很可能会为拟议的预警系统带来增量净效益，例如单个长期护理机构为17.2万美元，国家层面为350万 - 4100万美元。投资回报率和净效益的估计总体上较为稳健，不过应当指出的是，它们对发病率和长期护理机构对预警的依从性较为敏感。总之，这些研究结果明确了我们拟议的城市层面预警系统的潜在益处，该系统与新冠病毒的污水处理厂废水监测相结合时能产生净效益。
