Lemonia Anagnostopoulos

COVID-19 revealed a need to address known, expected and emerging infections on large passenger ships. HEALTHY SAILING (Project Nr: 101069764) provides an integrated, methodological approach to address this need. The three-year project is establishing an evidence-base for mechanisms facilitating infection spread onboard passenger ships and effectiveness of prevention, mitigation and management (PMM) measures. Foundational activities in the first year of implementation include systematic reviews, epidemiological studies, surveys and focus groups to identify risk factors, infection frequency, outbreak dynamics, and barriers to compliance with PMM measures. Mathematical models are being developed to predict infection spread onboard and evaluate measures’ impact. Computational Fluid Dynamics modelling explores airborne respiratory pathogen dispersion in ventilated spaces of cruise environments. An Integrated Health E-surveillance System is under development to perform real-time syndromic, laboratory and environmental health surveillance onboard, and will feed an AI Intelligence Immune System to produce health threat alerts, characterize threat levels and recommend/monitor health measures. A toolkit monitoring cleaning and disinfection is being prepared to improve effectiveness of current practices onboard, while a toolkit for technology-induced behavior change is underway, to improve hand hygiene practices onboard.

The emergence of SARS-CoV-2 variants of concern (VOCs) during the COVID-19 pandemic necessitates investigation into their clinical differentiation and outcomes. This study aimed to examine these differences among VOCs, considering multiple related factors. An observational cohort study was conducted on patients diagnosed with SARS-CoV-2 infection via nasopharyngeal/oropharyngeal swab who visited the emergency department of a public Greek hospital between October 2020 and July 2022 during different VOC circulation in the region. Data on clinical manifestations, outcomes, and medical history (comorbidities, prior SARS-CoV-2 infection, vaccination status against COVID-19) were collected through a questionnaire and medical records for those hospitalized. A total of 913 patients were included in this study (813 adults ≥18 years old, 100 children <18 years old). Significant differences were observed across VOCs for both adults and children. A lower proportion of children developed symptoms during the non-Omicron variants, 73.5%, compared to Omicron variants, 86.4%. Fever, dyspnea, and taste and smell disorders were observed more frequently among non-Omicron adult cases, in contrast to upper respiratory symptoms, which were more common symptoms among Omicron infections. The non-Omicron variants were associated with higher rates of hospitalization at 30.6%, pneumonia at 23.0%, and death at 6.1% compared to Omicron variants at 8.0%, 5.0%, and 1.8%, respectively. Vaccination against COVID-19 was shown to be a protective factor for severe outcomes. Our findings suggest distinct clinical presentations and outcomes associated with different VOCs. Despite the fact that current VOCs circulating are less severe, the COVID-19 vaccine continues to play a protective role for severe cases.

Background: Seasonal influenza vaccination (SIV) of health care workers (HCWs) is critical in protecting patients’ and HCWs’ health. Our objective was to examine HCW SIV coverage and related determinants. Methods and Materials: A nationwide cross-sectional questionnaire survey was conducted among HCWs during the first half of 2021. The questionnaire (online or paper-based) included knowledge, attitude and practice questions regarding SIV, COVID-19 vaccines and vaccination. Results: Out of 6500 questionnaires administered, 2592 were completed (response rate: 39.9%). SIV coverage reached 69.4% (95% CI: 67.6–71.2%) based on self-reported vaccine uptake. Nurses and administrative staff were found to be more skeptical and have lower vaccine acceptance in comparison with physicians (aOR = 0.66 and aQR = 0.59, respectively). Other SIV hesitancy risk factors included working in secondary health care (aOR = 0.59) and working in northern Greece (aQR = 0.66). Determinants for SIV acceptance included being or living with high-risk people due to medical history (aOR = 1.84 and aOR = 1.46, respectively), positive attitudes towards routine vaccinations (aOR: 1.86), knowledge about COVID-19 vaccines (aOR = 1.53) and COVID-19 vaccine uptake (aOR = 3.45). The primary reason for SIV refusal was low risk perception (58.7%). Conclusions: SIV coverage (2020/2021) was relatively high, but remained far from formal recommendations. Specific occupational groups were skeptical and low-risk perception was the main reason for vaccine refusal. Targeted policies should be developed and enforced.

Monitoring behavioral and cultural insights during the pandemic is a useful tool to identify factors related to COVID-19 vaccine acceptance and confront the pandemic’s vast impact. Data were collected using a questionnaire designed according to the “survey tool and guidance” provided by the World Health Organization (WHO). Surveys were conducted by a market research company for five consecutive months, with a sample of 1000 individuals recruited per survey. Vaccination acceptance increased from 55.2% to 67.2%, while the percentage of undecisive individuals decreased from 16.3% to 10.6%. The proportion of vaccine resistant participants remained relatively steady (25–30%). Knowledge about the pandemic and compliance with preventive measures was high (>90%). Factors associated with vaccination included: Increased age, male gender, influenza vaccination, following authorities’ recommendations, being informed by HCWs or formal information sources, care for others, concern about the country’s economic recession and health system overload. Pandemic fatigue was reflected across the surveys, indicated by a decrease in the intention to self-isolate and remain at home when ill. Despite the decrease of undecisive individuals, a firm core of vaccine resistant individuals may be responsible for the relatively lower vaccine coverage compared to northern EU countries. Study results could be useful for developing approaches tailored to a reluctant population.

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.

The coordination of public health events related to ships presents a challenge to the port health authorities, and communication means and routes are not well established. The EU Common Ship Sanitation Database provides a platform for port-to-port communication of public health events on board ships. The last seven years of operation, 64 public health events were communicated through the system by port health authorities from seven EU countries. Although the usage of the platform has been appreciated, promoted, and legislated in several EU MSs, actions at the national and EU levels are needed to promote the use of the platform by all EU MS are necessary.

The joint action EU HEALTHY GATEWAYS (EUHG) aimed to support cooperation and coordinated action of MS to improve their preparedness and response capacities at PoE, for preventing and combating cross-border health threats from the transport sector. The aim of this study is to present how EUHG supported strengthening of core public health capacities at ports during routine operations and the COVID-19 pandemic. Methods used included surveys, literature reviews, in(tra)-action reviews, focus and expert working groups, site visits, exercises, inspection grading system methodology. In addition, the EU Common Ship Sanitation Database (EUSIS) was used as a tool to collect information on health conditions on board and to share information about public health events. EUHG network established the EUPOENET and implemented the European passenger ship inspections programme implementation where 558 inspectors in the EU SIS recorded 33,184 Ship Sanitation Certificates, followed up >80 public health events via the port communication form out of which 22 were COVID-19 related, and recorded > 4600 hygienic deficiencies. EUHG developed a web-based, searchable catalogue of best practices, SOPs for mosquito surveillance and control, a model MoU describing cooperation among authorities at ports, a tool was produced for development/assessment of contingency plans (ports), a tool serving group-based discussions about what defines risk at port level. EUHG conducted training courses and European level multi-sectorial TTE. The EUHG network of experts supported EU’s COVID-19 response by developing 16 technical guidance documents, provided >40 expert consultations and conducted three site visits and short seminars, two national level IAR and a European level meeting using IAR methodology and produced over five scientific publications. The JA’s network contribution to the pandemic has been globally acknowledged, recognized and demonstrated, with the network immediately activated to support EC and MS requests, and transport restart operations in 2020–2021.

Waterborne disease due to the microbial contamination of potable water onboard ships is a potential threat for seafarers. The results from the samples collected at Belgian ports from 2010 to 2018 during inspections of non-passenger ships are used to evaluate the microbiological and chemical quality of potable water. A small proportion of the samples was found positive for indicator organisms (7.5%), indicating the lack of proper disinfection and possible contamination. Further analyses and risk assessments are recommended for examining possible contributing factors. Inspections for the issuance of SSC should focus on water safety and the prevention of waterborne diseases.

The association of cases of Legionnaires’ disease and ships has been well documented. Results from potable water samples collected for microbiological analysis during SSC inspections conducted from 2010 to 2018 at Belgian ports were analyzed in order to evaluate the level of colonization on non-passenger ships. Results indicate a high degree of colonization (77.2% of the ships were found to be colonized with Legionella spp. at least once) and further analysis is recommended to examine possible factors associated with colonization. Inspections for issuance of SSC should focus on water safety and prevention of Legionnaires’ disease.

The effectiveness of coronavirus disease 2019 (COVID-19) vaccination strategies is affected by several factors, including the genetic background of the host. In our study, we evaluated the contribution of the functional polymorphism rs1883832 affecting the Kozak sequence of the TNFSF5 gene (c.-1C>T), encoding CD40, to humoral immune responses after vaccination with the spike protein of SARS-CoV-2. The rs1883832 polymorphism was analyzed by PCR-RFLP in 476 individuals (male/female: 216/260, median age: 55.0 years, range: 20–105) of whom 342 received the BNT162b2 mRNA vaccine and 134 received the adenovirus-based vector vaccines (67 on ChAdOx1-nCoV-19 vaccine, 67 on Ad.26.COV2.S vaccine). The IgG and IgA responses were evaluated with chemiluminescent microparticle and ELISA assays on days 21, 42, and 90 after the first dose. The T allele of the rs1883832 polymorphism (allele frequency: 32.8%) was significantly associated with lower IgA levels and represented, as revealed by multivariable analysis, an independent risk factor for reduced anti-spike protein IgA levels on days 42 and 90 following BNT162b2 mRNA vaccination. Similar to serum anti-spike IgA levels, a trend of lower anti-spike IgA concentrations in saliva was found in individuals with the T allele of rs1883832. Finally, the intensity of IgA and IgG responses on day 42 significantly affected the prevalence of COVID-19 after vaccination. The rs1883832 polymorphism may be used as a molecular predictor of the intensity of anti-spike IgA responses after BNT162b2 mRNA vaccination.