Diamond Princess Research Articles

Evaluating infectious disease outbreak potential and mitigation effectiveness on cruise ships

The cruise ship sector is a major part of the tourism industry, and an estimated over 30 million passengers are transformed worldwide each year. Cruise ships bring diverse populations into proximity for many days, facilitating the transmission of respiratory illnesses. The objective of this study is to develop a modeling framework to inform the development of viable disease risk management policies and measures to control disease outbreaks on cruises. Our model, parameterized and calibrated using the data of the COVID-19 outbreak on the Diamond Princess cruise ship in 2020, is used to assess the impact of the mitigation measures such as mask wearing, vaccination, on-board and pre-traveling testing measures. Our results indicate mask wearing in public places as the cheapest and most affordable measure can drop the number of cumulative confirmed cases by almost 50%. This measure along with the vaccination by declining the number of the cumulative confirmed cases by more than 94% is the most effective measure to control outbreaks on cruises. According to our findings, outbreaks are more predominant in the passenger population than the crew members, however, the protection measures are more beneficial if they are applied by both crew members and passengers. Regarding the testing measure, pre-traveling testing is more functional than the on-board testing to control outbreaks on cruises.

Integrated infection and crowd behaviour model for COVID-19 infection risk assessment onboard large passenger vessels

The development of the global COVID-19 pandemic from 2020 onward has had significant impact on the world and specifically the maritime industry. Striking examples were COVID-19 outbreaks onboard the Diamond Princess cruise vessel and the U.S.S. Theodore Roosevelt aircraft carrier at the start of the pandemic. Contagious disease management onboard large passenger ships remains a complex issue, amplified by the international character of the industry, confined environment and shared facilities. This paper therefore presents an integrated infection and crowd behavior model used to calculate agent-specific infection risk, incorporating guest and crew circulation through a passenger ship layout. The integrated model is used to investigate the effect of ship layout design, capacity reduction and mask wearing on COVID-19 airborne infection risk onboard large passenger vessels.

Considerations in Bayesian agent‐based modeling for the analysis of COVID‐19 data

AbstractAgent‐based model (ABM) has been widely used to study infectious disease transmission by simulating behaviors and interactions of autonomous individuals called agents. In the ABM, agent states, for example infected or susceptible, are assigned according to a set of simple rules, and a complex dynamics of disease transmission is described by the collective states of agents over time. Despite the flexibility in real‐world modeling, ABMs have received less attention by statisticians because of the intractable likelihood functions which lead to difficulty in estimating parameters and quantifying uncertainty around model outputs. To overcome this limitation, a Bayesian framework that treats the entire ABM as a Hidden Markov Model has been previously proposed. However, existing approach is limited due to computational inefficiency and unidentifiability of parameters. We extend the ABM approach within Bayesian framework to study infectious disease transmission addressing these limitations. We estimate the hidden states, represented by individual agent's states over time, and the model parameters by applying an improved particle Markov Chain Monte Carlo algorithm, that accounts for computing efficiency. We further evaluate the performance of the approach for parameter recovery and prediction, along with sensitivity to prior assumptions under various simulation conditions. Finally, we apply the proposed approach to the study of COVID‐19 outbreak on Diamond Princess cruise ship. We examine the differences in transmission by key demographic characteristics, while considering two different networks and limited COVID‐19 testing in the cruise.

A social media analysis of quarantined passengers’ social-supported coping and resilience-building experiences

Cruise lines are adopting onboard quarantine as part of emergency response measures to the global pandemic. However, little is known about the social support embedded in the social-mediated communication process to assist passengers in coping and building resilience. Guided by the conservation of resource theory, this study adopted the netnography approach to analyze the online interactions between quarantined passengers on Diamond Princess and netizens. A qualitative approach was employed to analyze the content of a relational dataset consisting of 14 research subjects, 3,368 posts, and 67,964 comments. The results not merely showed the changing foci of the comments over time but also revealed the supporting role played by social media. The constant engagement with netizens provided passengers with information and social support, which contributed to their coping and resilience-building. These findings offer a new theoretical perspective on incorporating social media in tourism crisis management, as well as practical implications for cruise lines and tourism organizations to optimize their resource utilization for marketing recovery.

Lessons learned from practices during the initial response to COVID-19 on the cruise ship Diamond Princess.

The battle against coronavirus disease 2019 (COVID-19) still continues three years after the onset of the pandemic, but there are concerns about the next emerging infectious disease. This study reports the practices during the initial response to COVID-19 on the cruise ship Diamond Princess and lessons learned from a nursing perspective. During these practices, one of the authors dealt with a sample collection team from the Self-Defense Forces and collaborated with the Disaster Medical Assistance Team (DMAT), Disaster Psychiatric Assistance Team (DPAT), and other teams. They mentioned the passengers' state and the distress and fatigue of the personnel assisting them. This revealed the specifics of emerging infectious diseases and their commonalities, regardless of the disaster. Results identified three crucial points: i) predicting the impact of lifestyle changes on health due to isolation and implementing preventive measures, ii) protecting individual human rights and dignity even in health emergencies, and iii) support for personnel providing assistance.

Towards the Next Pandemic–What Have We Learned? Insights of a Large Tertiary Care Hospital

Introduction:The first cases of COVID-19 arrived in Israel in March 2020. In Israel, the first known cases were Israeli patients diagnosed with COVID-19 aboard the Diamond Princess which were repatriated.Shortly later, additional cases were found in increasing numbers constituting the "first wave". The high number of patients put significant strain on Israeli hospitals. The initial wave was later followed by additional surges in the number of patients further straining the system. At the peak, hospitals with a total bed capacity of 800 had 135 covid-19 patients with 21 of them requiring ventilatory support.Method:Daily and weekly multidisciplinary meetings were held and daily reports were composed. Following each wave, lessons learned and recommendations for improved preparedness were formulated. The following results and conclusion sections summarize some of the main insights and recommendations.Results:The main challenges in Beilinson hospital during the "first wave" were a shortage of personal protective equipment (PPE) and how to best utilize the existing supplies, uncertainty regarding infectiveness, best management practices and uncertainty regarding the expected magnitude and duration of the pandemic. In retrospect, the major insights were the need for a flexible and divisible ED to safely care for changing loads of suspected and verified COVID-19 patients as well as COVID-19 negative patients. Increasing the in-hospital stockpile of PPE as well as the regional and national stockpile and creating local production capacities. The importance of the daily multidisciplinary managerial meeting was to improve situational awareness and allow improved decision making. Staff briefing occurred on a daily basis and during times of high uncertainty at the beginning of every shift.Conclusion:Performing structured and frequent debriefing and analysis to achieve clinical and operational insights is crucial for improved short-term performance as well as improving preparedness for future challenges.

Reviewing the Implementation of the Emergency Medical Team Minimum Data Set

Introduction:The Emergency Medical Team (EMT) Strategic Advisory Group of the WHO has endorsed the EMT Minimum Data Set (MDS) Daily Reporting Form in 2017 and the revised EMT Minimum Standards of the WHO suggests EMTs report it regularly in case national reporting forms are not available.Method:This study searched and listed previous use cases of the MDS by reviewing published papers including gray literature and interviews with national authorities, organizations, and experts.Results:In 2019, the MDS had been activated for the first time in Mozambique during international scale response at the tropical cyclone Idai; also in Japan it was used at the typhoon Faxai/Hagibis response; further in the Independent State of Samoa during the measles outbreak. In 2020, the MDS was used during a COVID-19 mega-cluster incident on the Diamond Princess Cruise Ship in Japan, the tropical cyclone Harold in Vanuatu and the Kumamoto Heavy Rain in Japan. In 2021, the one was used during the Izuyama landslide response in Japan; and the typhoon Rai response in the Philippines. In 2022, it was used during the cyclone Batsirai response in Madagascar; and in Moldova, Poland, and Ukraine to respond to the armed conflict situation in Ukraine.Many countries are preparing to use the form; in 2022 the Association of SouthEast Asian Nations (ASEAN) has officially endorsed the form as a regional standard form for EMT daily reporting. Military partners also were testing the form, in 2019 forces from eight nations at the 39th Cobra Gold 20 in Thailand used the form for training purposes.Conclusion:The MDS was used in at least 14 emergencies in nine countries. Mozambique and Japan have published academic literature using the MDS. The use of MDS would strengthen Health Emergency and Disaster Risk Management (H-EDRM) in a data-based manner.

Diamond Princess Cruise Ship. COVID-19 Medical Operation by the National EMT, Japan DMAT.

Introduction:The Diamond Princess cruise ship (DP) arrived in Yokohama, Japan, on February 3, 2019, with a confirmation of the Polymerase Chain Reaction test (PCR) positive for the Coronavirus disease 2019 (COVID-19) in a passenger who disembarked at Hong Kong. Japan National Emergency Medical Team (N-EMT), and Japan Disaster Medical Assistance Team (DMAT), were dispatched and measures to prevent the spread of viruses were taken for 3,711 (2,666 passengers and 1,045 crew members) on board.Method:Japan DMAT was dispatched and managed the medical operation for DP passengers and crew members. The records of communication logs for the DMAT were evaluated. In this study, evaluation of DMAT medical operations in the DP was conducted to find any positive effectsResults:472 (157 doctors, 123 nurses, 161 medical logisticians, 31 pharmacists) members responded. Among them, 283 (97 doctors, 66 nurses, 91 medical logisticians, 29 pharmacists) worked inside the DP, and 189 (60 doctors, 57 nurses, 70 medical logisticians, two pharmacists) operated outside mainly for patient transport. DMAT conducted a strategic operation and developed categorization for medical care and patient transport. Eventually, DMAT constructed flow to provide rapid medical care and prescription distributions for passengers and crew members.Conclusion:DMAT has been required to respond to unforeseen disasters in the framework since the Fukushima Nuclear Plant accident in 2011. All the past several types of disaster response were contributed to managing medical operations at the DP. These operations are thought to reduce preventable deaths from COVID-19.

‘God forbid we’d be infected’: framing and counter-framing of the ‘Corona Cruise Ship’ in Israeli media

ABSTRACT This article explores framing and online counter-framing within an Israeli cultural context. It investigates the case study of the Corona Cruise Ship (Diamond Princess), applying qualitative, inductive frame analysis to two content samples: all (N = 47) news articles published regarding the Corona Cruise Ship on two popular Israeli news sites (News 12 Company and YNET News); 342 randomly sampled, individual posts from the articles’ comments section. Findings reveal a ‘Solidarity as unity’ frame in the news coverage and four public counter-frames differing from the Israeli media’s frame: ‘Solidarity as selfishness’, ‘A moral lesson for hedonists’, ‘Divine punishment’, and ‘The politics of outbreaks and elections’. They also highlight various challenges facing framing and counter-framing research in an online environment.

Compulsory insurance for cruise vessels as a preparation for the next pandemic: Law of the sea perspective

During the COVID-19 pandemic, many port states faced difficulty when cruise vessels with COVID-19 patients tried to dock at their ports. Although they are basically not obliged to accept such vessels under international law, they cannot easily deny access because the refusal would be viewed as a lack of humanitarian consideration. On the other hand, accepting such vessels leads to the risk of exposing their own nationals to COVID-19 and incurring the financial cost of medical treatment for cruise passengers. In fact, in the cases of Diamond Princess, Costa Atlantica, and Zaandam and Rotterdam, the question of who should take on the financial burden for medical costs of crews and passengers on board these vessels was debated. The current international legal framework does not provide any answer to this question, and therefore, a new framework is needed. If the new framework allocates the economic burden to ensure the provision of tests and medical care so that an intolerably heavy burden is not imposed on port states, they will be more welcoming to cruise vessels with infected people. Such allocation could be realized by requesting that carriers provide a compulsory insurance system for medical care in a pandemic.

A novel nonparametric mixture model for the detection pattern of COVID-19 on Diamond Princess cruise

The outbreak of COVID-19 on the Diamond Princess cruise ship has attracted much attention. Motivated by the PCR testing data on the Diamond Princess, we propose a novel cure mixture nonparametric model to investigate the detection pattern. It combines a logistic regression for the probability of susceptible subjects with a nonparametric distribution for the detection of infected individuals. Maximum likelihood estimators are proposed. The resulting estimators are shown to be consistent and asymptotically normal. Simulation studies demonstrate that the proposed approach is appropriate for practical use. Finally, we apply the proposed method to PCR testing data on the Diamond Princess to show its practical utility.

Transmission of SARS-CoV-2 Associated with Cruise Ship Travel: A Systematic Review.

Background: Maritime and river travel may be associated with respiratory viral spread via infected passengers and/or crew and potentially through other transmission routes. The transmission models of SARS-CoV-2 associated with cruise ship travel are based on transmission dynamics of other respiratory viruses. We aimed to provide a summary and evaluation of relevant data on SARS-CoV-2 transmission aboard cruise ships, report policy implications, and highlight research gaps. Methods: We searched four electronic databases (up to 26 May 2022) and included studies on SARS-CoV-2 transmission aboard cruise ships. The quality of the studies was assessed based on five criteria, and relevant findings were reported. Results: We included 23 papers on onboard SARS-CoV-2 transmission (with 15 reports on different aspects of the outbreak on Diamond Princess and nine reports on other international cruises), 2 environmental studies, and 1 systematic review. Three articles presented data on both international cruises and the Diamond Princess. The quality of evidence from most studies was low to very low. Index case definitions were heterogeneous. The proportion of traced contacts ranged from 0.19 to 100%. Studies that followed up >80% of passengers and crew reported attack rates (AR) up to 59%. The presence of a distinct dose–response relationship was demonstrated by findings of increased ARs in multi-person cabins. Two studies performed viral cultures with eight positive results. Genomic sequencing and phylogenetic analyses were performed in individuals from three cruises. Two environmental studies reported PCR-positive samples (cycle threshold range 26.21–39.00). In one study, no infectious virus was isolated from any of the 76 environmental samples. Conclusion: Our review suggests that crowding and multiple persons per cabin were associated with an increased risk of transmission on cruise ships. Variations in design, methodology, and case ascertainment limit comparisons across studies and quantification of transmission risk. Standardized guidelines for conducting and reporting studies on cruise ships of acute respiratory infection transmission should be developed.

A major outbreak of the COVID-19 on the Diamond Princess cruise ship: Estimation of the basic reproduction number.

The COVID-19 pandemic, which broke out in Wuhan, China, in 2019, was declared an international public health emergency by the World Health Organization on January 31, 2020. The outbreak on the Diamond Princess cruise ship had appeared first as a cluster infection outside China during the early pandemic. The incident occurred on February 1, 2020, involved an 80-year-old Hong Kong man who was diagnosed with COVID-19. The cruise ship docked in Yokohama, Japan, for 14 days of onboard quarantine; however, cluster infection outbroke rapidly. We constructed a SIR mathematical model and conducted an epidemiological study of the COVID-19 outbreak on the Diamond Princess cruise ship, covering the period from February 5 (start of quarantine) to February 20 (completion of 14-day quarantine). We estimated the basic reproduction number (R 0 ) using a novel method of nonlinear least-squares curve fitting under Microsoft Excel Solver. The 95% confidence interval (CI) values were estimated by the jackknife procedures. Six hundred thirty-four (17.1%) cases were diagnosed in a total population of 3711 cruise passengers, and 328 (51.7%) cases were asymptomatic. As of April 24, 2020, 712 cases had been diagnosed and 14 (1.96%) deaths had occurred. The R 0 with 95% CI of the COVID-19 outbreak was 3.04 (2.72-3.36). Without an evacuation plan for passengers and crew, we estimated the total number of cumulative cases would reach 3498 (CI, 3464-3541). If the R 0 value was reduced by 25% and 50%, the cumulative cases would be reduced to 3161 (CI, 3087-3254) and 967 (CI, 729-1379), respectively. The abovementioned R 0 value was estimated from the original Wuhan strain. Cruise conditions would accelerate the spread of infectious diseases and were not suitable for onboard quarantine. Early evacuation and isolation of all passengers and crew members would reduce the R 0 value and avoid further infections.

Mental health needs associated with COVID-19 on the diamond princess cruise ship: A case series recorded by the disaster psychiatric assistance team

Coronavirus disease 2019 (COVID-19) infection prevention measures have led to a variety of mental health issues. Although several self-care methods have been recommended for those quarantined, evidence regarding how best to support quarantined people experiencing a mental health crisis is limited.In February 2020, the Diamond Princess cruise ship was quarantined in Yokohama port, Japan following a passenger testing positive for COVID-19. We were sent to address the mental health issues as the Disaster Psychiatric Assistance Team (DPAT). In the present study, we examined the acute mental health needs of the passengers and crew collected by the DPAT using the standard Emergency Medical Team daily reporting system.We assessed 206 cases (99 men and 107 women) with generic health issues and 127 cases (39 men and 88 women) with mental health issues. Mental health issues including disaster stress-related symptoms were as frequent as physical health events associated with COVID-19. The most significant mental health issue was anxiety, as an acute psychological reaction to the quarantine situation. Women and crews most frequently needed mental health support. Mental health improved in most clients after brief counseling. Although several passengers experienced suicidal ideation, there were no cases of actual suicide attempts during the quarantine period.This case has been regarded as a well-known public health event at the beginning of the COVID-19 era. In addition to physical health support, disaster mental health support was essential to save lives. Our findings may facilitate responses to future quarantines, accidents, and mental health crises.

Cruise tourism in the context of COVID-19: Dilemmas and solutions

COVID-19 cases on international cruise ships have attracted extensive attention from the international community as well as the world's tourism and shipping industry. This virus highlighted the plight that must be faced by cruise ships in complicated times and situations such as pandemics. The comparative method is adopted to analyze the management measures taken by the “Diamond Princess”, “Costa Serena”, “Westerdam” and “Grand Princess” cruises in response to the COVID-19 pandemic and then to summarize the common dilemmas faced by these cruise ships, including defects of their internal environment, unclear health-care obligations during an epidemic, weak collaboration between the parties involved and their limited performance, and widespread infodemic and unfavorable public opinion. Given these dilemmas, measures are suggested to deal with the “cruise dilemma”, including establishing and defining isolation standards on boards, enhancing the capacity of international organizations, the international community's joint response to the pandemic, promoting cooperation between countries, building an effective mechanism for the broad participation of the whole society, and standardizing the release of information and reasonably guiding public social opinion.

Dire Straits: How tourists on the Diamond Princess cruise endured the COVID-19 crisis.

Despite insights about tourists' health risk perception, crisis management literature still lacks understanding of how tourists actually experience ongoing crises and how their in situ perception evolves. Drawing on the unique case of the quarantine of the Diamond Princess at the Port of Yokohama in early February 2020, this study investigates how tourists intuitively and affectively enact the scene of a crisis in their concurrent discourses. A unique dataset covering 2259 social media entries by tourists during the quarantine were compiled manually and examined. Tourists' concerns and emotions demonstrate two salient characteristics of the enactment of the crisis scene: expressing cautious optimism and crafting realistic lifestyle. Findings demonstrate the resilience of tourists under extreme circumstances, elucidate similarities and differences of tourists' experience mediated by language, and show their supportive attitude toward tourist industry players. Service providers can strategically use of tourists' sensemaking and psychological resilience to improve market images.

Identifying Risks in the Cruise Supply Chain: An Empirical Study in Shanghai, China

The increased frequency and severe consequences of risks in the cruise industry have attracted increasing attention from both academics and practitioners, especially after the 2012 ‘Costa Concordia’ disaster and the 2020 coronavirus outbreak on the ‘Diamond Princess’. Although the literature on risk studies associated with the cruise industry and supply-chain risk management is growing, the extant literature lacks a study to view risks in the cruise industry associated with the supply chain. This paper addresses this gap by reviewing the literature on risks related to the cruise industry and general supply-chain risks to create a framework of cruise supply-chain risks. Then, semi-structured interviews were conducted to validate the identified risks and explore potential undiscovered risks. A novel risk typology of the cruise supply chain was then built based on the literature review and the empirical study. This includes macro risks, safety, security, and health risks, information risks, and supply risks. This framework can be applied for the purpose of systematically identifying the risks and their impacts on the cruise supply chain. This paper contributes to the development of a comprehensive cruise supply-chain risk classification with a detailed explanation of each risk in the cruise supply chain, which can be used by stakeholders in the cruise industry to identify and measure the impact of each risk. Additionally, this paper provides avenues for future research by scholars interested in assessing and managing cruise supply-chain risks.

Modelling COVID-19 outbreak on the Diamond Princess ship using the public surveillance data.

The novel coronavirus disease 2019 (COVID-19) outbreak on the Diamond Princess (DP) ship has caused over 634 cases as of February 20, 2020. We model the transmission process on DP ship as a stochastic branching process, and estimate the reproduction number at the innitial phase of 2.9 (95%CrI: 1.7–7.7). The epidemic doubling time is 3.4 days, and thus timely actions on COVID-19 control were crucial. We estimate the COVID-19 transmissibility reduced 34% after the quarantine program on the DP ship which was implemented on February 5. According to the model simulation, relocating the population at risk may sustainably decrease the epidemic size, postpone the timing of epidemic peak, and thus relieve the tensive demands in the healthcare. The lesson learnt on the ship should be considered in other similar settings.

The Occurrence Birth-Death Process for Combined-Evidence Analysis in Macroevolution and Epidemiology.

Phylodynamic models generally aim at jointly inferring phylogenetic relationships, model parameters, and more recently, the number of lineages through time, based on molecular sequence data. In the fields of epidemiology and macroevolution, these models can be used to estimate, respectively, the past number of infected individuals (prevalence) or the past number of species (paleodiversity) through time. Recent years have seen the development of “total-evidence” analyses, which combine molecular and morphological data from extant and past sampled individuals in a unified Bayesian inference framework. Even sampled individuals characterized only by their sampling time, that is, lacking morphological and molecular data, which we call occurrences, provide invaluable information to estimate the past number of lineages. Here, we present new methodological developments around the fossilized birth–death process enabling us to (i) incorporate occurrence data in the likelihood function; (ii) consider piecewise-constant birth, death, and sampling rates; and (iii) estimate the past number of lineages, with or without knowledge of the underlying tree. We implement our method in the RevBayes software environment, enabling its use along with a large set of models of molecular and morphological evolution, and validate the inference workflow using simulations under a wide range of conditions. We finally illustrate our new implementation using two empirical data sets stemming from the fields of epidemiology and macroevolution. In epidemiology, we infer the prevalence of the coronavirus disease 2019 outbreak on the Diamond Princess ship, by taking into account jointly the case count record (occurrences) along with viral sequences for a fraction of infected individuals. In macroevolution, we infer the diversity trajectory of cetaceans using molecular and morphological data from extant taxa, morphological data from fossils, as well as numerous fossil occurrences. The joint modeling of occurrences and trees holds the promise to further bridge the gap between traditional epidemiology and pathogen genomics, as well as paleontology and molecular phylogenetics. [Birth–death model; epidemiology; fossils; macroevolution; occurrences; phylogenetics; skyline.]

Heterogeneous epidemic modelling within an enclosed space and corresponding Bayesian estimation.

Since March 11th, 2020, COVID-19 has been a global pandemic for more than one years due to a long and infectious incubation period. This paper establishes a heterogeneous epidemic model that divides the incubation period into infectious and non-infectious and employs the Bayesian framework to model the ‘Diamond Princess’ enclosed space incident. The heterogeneity includes two different identities, two transmission methods, two different-size rooms, and six transmission stages. This model is also applicable to similar mixed structures, including closed schools, hospitals, and communities. As the COVID-19 pandemic continues, our mathematical modeling can provide management insights to the governments and policymakers on how the COVID-19 disease has spread and what prevention strategies still need to be taken.