Interventional Study of Nonpharmaceutical Measures to Prevent COVID-19 Aboard Cruise Ships.

Cruise ships carrying COVID-19-vaccinated populations applied near-identical nonpharmaceutical measures during July-November 2021; passenger masking was not applied on 2 ships. Infection risk for masked passengers was 14.58 times lower than for unmasked passengers and 19.61 times lower than in the community. Unmasked passengers' risk was slightly lower than community risk.

Systematic literature review and meta-analysis on preventing and controlling norovirus outbreaks on cruise ships, 1990 to 2020: calling for behaviour change strategies of travellers.

BackgroundOutbreaks of norovirus gastroenteritis aboard cruise ships may affect a large number of people, debilitate vulnerable travellers, disrupt vacations and cause economic losses to the cruise ship industry.AimWe aimed to identify risk factors for norovirus outbreaks on cruise ships and assess the effectiveness of prevention and control measures.MethodsWe conducted a systematic literature review searching PubMed and Scopus databases as well as grey literature for articles and reports describing norovirus outbreaks on cruise ships between 1990 and 2020. We also performed a meta-analysis of norovirus prevalence in passengers and crew members.ResultsData from 45 outbreaks on 26 cruise ships from 1990 to 2020 were identified in 13 articles and five reports, with a weighted average of prevalence (attack rate) for passengers of 7% (95% confidence interval (CI): 5.00-9.00) and for crew of 2% (95% CI: 0.00-3.00). Person-to-person was the most frequent mode of transmission in 35 of the 45 outbreaks (in 14 the only mode and in 21 as part of multiple transmission routes). Having an ill cabin mate (OR = 38.70; 95% CI: 13.51-110.86) was the most common risk factor. Six outbreak investigations reported poor hygiene, while four reported satisfactory hygiene in the cruise setting. Behavioural risk factors among travellers were investigated in three of the 13 studies.ConclusionsThe findings indicate a need for behavioural interventions to improve personal hygiene, symptom reporting and compliance with isolation measures, and for reconsidering current isolation policies where symptomatic and healthy individuals are isolated in the same cabin.

Re-Starting the Cruise Sector during the COVID-19 Pandemic in Greece: Assessing Effectiveness of Port Contingency Planning.

Coronavirus disease (COVID-19) outbreaks on board cruise ships early in the pandemic highlighted gaps worldwide in public health emergency contingency plans (PHECPs) for responding to unknown threats. To restart cruise operations in 2021 and respond to potential COVID-19 outbreaks, a major tourist-based Greek island port (Port A) developed a COVID-19 PHECP. We assessed plan effectiveness by reviewing epidemiological data and monitoring outcomes, followed by an intra-action review (IAR) analyzing three event responses. From May to December 2021, 118 calls from 23 cruise ships with 119,930 passengers were recorded, with 29 COVID-19 cases in 11 cruises on board 7 ships. No outbreak was recorded during the study period. Strengths of the introduced PHECP included commitment of senior management; a core multi-disciplinary team of local authorities/ship agents involved in design and execution; interoperability agreements for port and ships' PHECPs; cruise industry commitment to compliance; and pre-existing scenarios considering capacity needs. Central government coordination for preparedness planning at local ports is essential for successful responses. Monitoring local and country level response capacities is critical to inform planning, risk assessment, and decision-making. Immediately recording ports' response actions provides the basis to capture lessons and improve contingency plans. To facilitate communication and common response protocols between European and non-European ports, IARs should be conducted between countries.

Nationwide Survey in Greece about Knowledge, Risk Perceptions, and Preventive Behaviors for COVID-19 during the General Lockdown in April 2020.

BACKGROUND: The aim of this study was to investigate the knowledge, attitudes, and practices of the Greek general population toward coronavirus disease 2019 (COVID-19) during the lockdown period in April 2020, to examine factors associated with misperceptions and to determine behavioral patterns that may require interventions. METHODS: A cross-sectional study of the general Greek population (N = 1858) was conducted. A geographically stratified cluster sampling was implemented. A questionnaire was composed consisting of 35 questions. Data collection took place from 15 April to 2 May 2020. A random-digit dialing survey was conducted by 29 interviewers. RESULTS: The majority of respondents (62.7%) answered ≥12/17 questions correctly. Participants aged 18-44 years, male gender, specific occupations (freelancer, unemployed, housewife, retiree) and those who sought information about COVID-19 from less than two sources received lower aggregated scores on knowledge questions. Regarding attitudes toward future vaccination, 18.9% declared that were against it, while 81.1% that they may consider or will be vaccinated. About 40% were not using a face mask and only 42% washed their hands appropriately. CONCLUSION: Adjusting information campaigns targeting especially people below 45 years of age can help to sensitize them and realise their role to control the spread. Further targeted surveys are needed to adjust/design prevention campaigns.

Environmental contamination of SARS-CoV-2 on surfaces, air-conditioner and ventilation systems.

BACKGROUND: COVID-19 can be transmitted directly through respiratory droplets or indirectly through fomites. SARS-CoV-2 has been detected on various environmental surfaces, air samples and sewage in hospital and community settings. METHODS: Environmental samples were collected from a ferryboat during a COVID-19 ongoing outbreak investigation and a nursing home and from three COVID-19 isolation hospital wards and a long-term care facility where asymptomatic COVID-19 cases were isolated. Samples were tested by real-time reverse transcriptase-polymerase chain reaction. RESULTS: SARS-CoV-2 was detected on swab samples taken from surfaces of food preparation and service areas, hospital isolation wards, an air exhaust duct screen, air-conditioning filter, sewage treatment unit and air sample during investigations conducted in response to COVID-19 outbreaks on a ferryboat, nursing home, isolation facility and COVID-19 hospital wards. DISCUSSION: Food preparation areas and utensils can be contaminated during COVID-19 outbreaks. Respiratory droplets/nuclei from infected persons can be displaced by the air flow and deposited on surfaces. It can be assumed that in the same manner, air flow could transfer and deposit infected respiratory droplets/nuclei from infected persons to the mucous membranes of persons standing against the air flow direction.