BACKGROUND: 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. MATERIAL AND METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.
BACKGROUND: 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. MATERIAL AND METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.
Authors: Marion E Rice; Millicent Bannerman; Mona Marin; Adriana S Lopez; Melissa M Lewis; Caroline E Stamatakis; Joanna J Regan Journal: Travel Med Infect Dis Date: 2018-04-03 Impact factor: 6.211
Authors: Varvara A Mouchtouri; Hannah C Lewis; Christos Hadjichristodoulou Journal: Int J Environ Res Public Health Date: 2019-07-30 Impact factor: 3.390
Authors: Ann-Christin Kordsmeyer; Natascha Mojtahedzadeh; Jan Heidrich; Kristina Militzer; Thomas von Münster; Lukas Belz; Hans-Joachim Jensen; Sinan Bakir; Esther Henning; Julian Heuser; Angelina Klein; Nadine Sproessel; Axel Ekkernkamp; Lena Ehlers; Jens de Boer; Scarlett Kleine-Kampmann; Martin Dirksen-Fischer; Anita Plenge-Bönig; Volker Harth; Marcus Oldenburg Journal: Int J Environ Res Public Health Date: 2021-05-13 Impact factor: 3.390