A new hospital building was close to completion when a large pipe carrying clean water broke, causing extensive flooding. To determine the flood-associated fungal risk to susceptible patients who would use that building. Though standard flood remediation by the builders was relatively straightforward, there was no model for specialist assessment of patient risk due to the flood-associated mould growth. As levels of background airborne fungal spores can be expected to vary significantly over time, we could not use absolute levels to indicate either an excess of airborne fungal spores or successful remediation. Therefore it was decided to use weekly settle plates, exposed at the same time in flooded (test) and equivalent non-flooded (control) areas to compensate for variations in background levels. Flood-related risk was estimated by the ratio between fungal colonies on the test and control sets of settle plates, rather than absolute number. Whereas the physical flood remediation, including the use of ‘anti-fungal’ treatments, was completed in three weeks post flooding, fungal contamination in flooded areas took 38 weeks to return to control levels and remained so for a further six weeks of observation. By the use of this method, we were able to assure the absence of flood-associated fungal risk to susceptible patients who would use that building. We recommend that infection prevention and control teams consider using this approach should they be faced with similar situations.

中文翻译：

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大范围洪水后医疗保健环境中霉菌修复的评估

一座新医院大楼即将竣工时，一根输送洁净水的大管道破裂，导致大面积洪水。确定使用该建筑的易感患者与洪水相关的真菌风险。尽管建筑商的标准洪水修复相对简单，但由于与洪水相关的霉菌生长，没有对患者风险进行专业评估的模型。由于背景空气中真菌孢子的水平预计会随着时间的推移而发生显着变化，因此我们无法使用绝对水平来表明空气中真菌孢子过量或修复成功。因此，决定使用每周沉降板，同时暴露在淹没（测试）和等效的非淹没（对照）区域，以补偿背景水平的变化。与洪水相关的风险是通过沉降板上测试集和对照集的真菌菌落之间的比率而不是绝对数量来估计的。尽管物理洪水修复（包括使用“抗真菌”处理）在洪水发生后三周内完成，但洪水地区的真菌污染需要 38 周才能恢复到控制水平，并在接下来的六周观察中保持这种状态。通过使用这种方法，我们能够确保使用该建筑的易感患者不存在与洪水相关的真菌风险。我们建议感染预防和控制团队在遇到类似情况时考虑使用这种方法。