School of Public Health and Management, Research Center for Medicine and Social Development, Innovation Center for Social Risk Governance in Health, Chongqing Medical University, Yixueyuan Road, Yuzhong District, Chongqing, 400016, China.
Office of Health Emergency, Chongqing Municipal Health Commission, No.6, Qilong Road, Yubei District, Chongqing, 401147, China.
Environ Health Prev Med. 2021 Apr 19;26(1):49. doi: 10.1186/s12199-021-00971-z.
Understanding the association between floods and bacillary dysentery (BD) incidence is necessary for us to assess the health risk of extreme weather events. This study aims at exploring the association between floods and daily bacillary dysentery cases in main urban areas of Chongqing between 2005 and 2016 as well as evaluating the attributable risk from floods.
The association between floods and daily bacillary dysentery cases was evaluated by using distributed lag non-linear model, controlling for meteorological factors, long-term trend, seasonality, and day of week. The fraction and number of bacillary dysentery cases attributable to floods was calculated. Subgroup analyses were conducted to explore the association across age, gender, and occupation.
After controlling the impact of temperature, precipitation, relative humidity, long-term trend, and seasonality, a significant lag effect of floods on bacillary dysentery cases was found at 0-day, 3-day, and 4-day lag, and the cumulative relative risk (CRR) over a 7-lag day period was 1.393 (95%CI 1.216-1.596). Male had higher risk than female. People under 5 years old and people aged 15-64 years old had significantly higher risk. Students, workers, and children had significantly higher risk. During the study period, based on 7-lag days, the attributable fraction of bacillary dysentery cases due to floods was 1.10% and the attributable number was 497 persons.
This study confirms that floods can increase the risk of bacillary dysentery incidence in main urban areas of Chongqing within an accurate time scale, the risk of bacillary dysentery caused by floods is still serious. The key population includes male, people under 5 years old, students, workers, and children. Considering the lag effect of floods on bacillary dysentery, the government and public health emergency departments should advance to the emergency health response in order to minimize the potential risk of floods on public.
了解洪水与细菌性痢疾（BD）发病率之间的关联，对于评估极端天气事件对健康的风险十分必要。本研究旨在探讨 2005 年至 2016 年期间重庆市主城区洪水与每日细菌性痢疾病例之间的关联，并评估洪水的归因风险。
采用分布式滞后非线性模型，控制气象因素、长期趋势、季节性和星期几，评估洪水与每日细菌性痢疾病例之间的关联。计算洪水导致的细菌性痢疾病例的比例和数量。进行亚组分析以探讨不同年龄、性别和职业人群的关联。
在控制温度、降水、相对湿度、长期趋势和季节性的影响后，发现洪水对细菌性痢疾病例存在显著的滞后效应，滞后 0 天、3 天和 4 天，7 天滞后期的累积相对风险（CRR）为 1.393（95%CI 1.216-1.596）。男性的风险高于女性。5 岁以下和 15-64 岁的人群风险显著升高。学生、工人和儿童的风险显著升高。在研究期间，基于 7 天滞后日，洪水导致的细菌性痢疾病例归因分数为 1.10%，归因病例数为 497 例。
本研究证实，在准确的时间尺度内，洪水可增加重庆市主城区细菌性痢疾发病率的风险，洪水导致的细菌性痢疾风险仍然严重。重点人群包括男性、5 岁以下人群、学生、工人和儿童。考虑到洪水对细菌性痢疾的滞后效应，政府和公共卫生应急部门应提前采取应急卫生响应措施，以最大限度地降低洪水对公众的潜在风险。
