Acevedo Fabio, Diskin Arthur L, Dahl Eilif
Medical & Public Health Department, Royal Caribbean Cruises Ltd, Miami, Florida, USA.
Int Marit Health. 2011;62(4):254-61.
Being highly contagious by person-to-person transmission, varicella can easily spread within the multinational population of a cruise ship and into communities ashore. The aim of the study was to report the prevalence of varicella infections in a fleet of cruise ships during a two-year period and to discuss measures to prevent and contain shipboard outbreaks.
All probable varicella cases among passengers and crew on 34 cruise ships were registered for 2 years by the medical facilities onboard. Patients remained isolated until 6 days after rash onset. Susceptible contacts were identified and offered post-exposure prophylaxis. Crew nationality, number of vaccinated contacts, and direct vaccination costs were registered.
During two years 187 varicella cases (36 passengers, 151 crew) were registered and 2,685 varicella vaccinations were administered at an estimated direct vaccination cost of US $ 283,832. Of the 34 ships, only 3 reported no cases of varicella. There were 8 clusters ('outbreaks') of ≥ 5 varicella cases presenting less than 42 days apart, comprising a total of 89 patients. While > 130 nations were represented among the crew, the 151 crew cases came from 26 countries, and 88 (58%) of them came from 5 sub-tropical/tropical countries.
All cruise vessels must expect to encounter varicella cases or outbreaks onboard every few years. Every varicella case can start an outbreak and thus trigger several time-consuming and expensive containment measures, including isolation and mass vaccination of susceptible contacts. Mandatory pre-contract evidence of varicella immunity from all seafarers or from subgroups according to position or nationality might be worth considering. Seafarers known to be immune to varicella should always carry valid documentation while traveling.
水痘具有高度的人际传播传染性，容易在游轮上的多国人群中传播，并蔓延到岸上社区。本研究的目的是报告两年期间游轮舰队中水痘感染的患病率，并讨论预防和控制船上疫情的措施。
船上医疗设施对34艘游轮上的乘客和船员中所有可能的水痘病例进行了为期2年的登记。患者一直隔离至出疹后6天。确定易感接触者并提供暴露后预防措施。记录船员国籍、接种疫苗的接触者数量和直接疫苗接种费用。
在两年期间，共登记了187例水痘病例（36名乘客，151名船员），并进行了2685次水痘疫苗接种，估计直接疫苗接种费用为283,832美元。在34艘船中，只有3艘报告没有水痘病例。有8个聚集性病例（“疫情”），每个聚集性病例中有≥5例水痘病例，且发病间隔时间少于42天，共有89名患者。虽然船员来自超过130个国家，但151名船员病例来自26个国家，其中88例（58%）来自5个亚热带/热带国家。
所有游轮每隔几年都有可能在船上遇到水痘病例或疫情。每一例水痘病例都可能引发疫情，从而触发多项耗时且昂贵的控制措施，包括隔离和对易感接触者进行大规模疫苗接种。或许值得考虑要求所有海员或根据职位或国籍划分的亚组提供水痘免疫的强制性合同前证据。已知对水痘免疫的海员在旅行时应始终携带有效证明文件。
