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.

Background: Outbreaks 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. Aim: We aimed to identify risk factors for norovirus outbreaks on cruise ships and assess the effectiveness of prevention and control measures. Methods: We 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. Results: Data 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. Conclusions: The 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.

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.

In response to the COVID-19 pandemic, the European Union Joint Action HEALTHY GATEWAYS developed guidelines for cruise operators and authorities to restart operations and provide common COVID-19 public health preparedness and response standards. In February 2022 under the Joint Action framework, a COVID-19 outbreak onboard a cruise ship was analysed, applying the Intra-Action Review (IAR) methodology at a European level. Participants included national public health authorities and local port health authorities involved in the event response, as well as cruise line representatives. Good practices and challenges observed during the COVID-19 event are presented. Moreover, we documented the lessons learned which provided the basis for proposed revisions to future versions of HEALTHY GATEWAYS guidelines.

This study evaluated the usefulness and validity of wastewater SARS-CοV-2 monitoring in passenger ships. Wastewater grab samples (n = 54) were collected from seven cruise ships arriving at the port of Piraeus from June to November 2021. Samples were analyzed for the presence of SARS-CoV-2 RNA with an RT-PCR based method. Results were compared against the number of cases detected on the ships before arrival. It was demonstrated that sewage monitoring can detect the presence of SARS-CoV-2, even with few cases on board. Future efforts should focus on the collection of more representative samples to increase the consistency and validity of the investigated practice.

Background: Inter-country communication and structured information flow is of major importance in outbreak management potentially affecting more than one country, particularly in case of a public health event of international concern. Though there are established communication systems in European Member States (MS), public health events in the maritime sector challenge authorities and stakeholders. Methods: Guidelines for inter-country communication developed by the joint action were tested via a 1-day web-based multi-sectorial, discussion-based table-top exercise (TTE) for ports at European level. Two outbreak scenarios (gastroenteritis and COVID-19) on passenger ships in separate regions (Mediterranean, North Sea) were acted out consecutively. Results: Thirty participants and 63 observers from 20 MS, cruise ships, international and European institutions took part in the TTE. The TTE identified two different information flows: (1) authorities at local level implementing public health measures on ships share information with the next and previous ports of call, either directly or via national level authorities using different platforms depending on the event without clearly predefined criteria and (2) the ship captain sends health information to the next port of call (via the National Single Window or Email or Telephone or other means). Relying on communication via emails and telephones however, has limitations: a) limited access, b) no central data storage, c) historical data unavailable. Lack of communication channels for feedback to the ship and of coordinating and closing an event was evident. Conclusions: A successfully conducted European TTE in maritime outbreak scenarios identified lack of clear international communication as communication channels were not always clear and depend on local/national conditions. There is potential for improving international communication. Guidelines for inter-country communication in this setting may help enhance communication practice.