MMWR Morb Mortal Wkly Rep. 2024 Oct 24;73(42):950-954. doi: 10.15585/mmwr.mm7342a3.
Legionnaires disease is a serious pneumonia caused by Legionella bacteria. During November 2022-June 2024, CDC was notified of 12 cases of Legionnaires disease among travelers on two cruise ships; eight on cruise ship A and four on cruise ship B. CDC, in collaboration with the cruise lines, initiated investigations to ascertain the potential sources of on-board exposure after notification of the second potentially associated case for each ship. Epidemiologic data collected from patient interviews and environmental assessment and sampling results identified private hot tubs on selected cabin balconies as the most likely exposure source. To minimize Legionella growth, both cruise lines modified the operation and maintenance of these devices by removing the heating elements, draining water between uses, and increasing the frequency of hyperchlorination and cleaning. Hot tubs offer favorable conditions for Legionella growth and transmission when maintained and operated inadequately, regardless of location. Private hot tubs on cruise ships are not subject to the same maintenance requirements as are public hot tubs in common areas. Given the range of hot tub-type devices offered as amenities across the cruise industry, to reduce risk for Legionella growth and transmission, it is important for cruise ship water management program staff members to inventory and assess private balcony hot tubs and adapt public hot tub maintenance and operations protocols for use on private outdoor hot tubs.
军团病是一种由军团菌引起的严重肺炎。在 2022 年 11 月至 2024 年 6 月期间，疾病预防控制中心接到两艘游轮上旅行者中 12 例军团病的通知；8 例在游轮 A，4 例在游轮 B。疾病预防控制中心与游轮公司合作，在每艘船通知第二例潜在相关病例后，启动调查以确定船上接触的潜在来源。从患者访谈和环境评估中收集的流行病学数据以及采样结果确定，选定客舱阳台的私人热水浴缸是最有可能的暴露源。为了尽量减少军团菌的生长，两家游轮公司通过拆除加热元件、在使用之间排空水以及增加超氯化和清洁的频率来修改这些设备的操作和维护。私人热水浴缸在维护和操作不当的情况下，无论位置如何，都会为军团菌的生长和传播提供有利条件。游轮上的私人热水浴缸不受公共区域公共热水浴缸相同的维护要求的限制。鉴于游轮行业提供的各种热水浴缸类型的设备，为了降低军团菌生长和传播的风险，游轮水管理计划工作人员重要的是要对私人阳台热水浴缸进行清查和评估，并调整公共热水浴缸的维护和操作协议，以便在私人户外热水浴缸上使用。
