Satellite mapping reveals extensive industrial activity at sea.

The world's population increasingly relies on the ocean for food, energy production and global trade1-3, yet human activities at sea are not well quantified4,5. We combine satellite imagery, vessel GPS data and deep-learning models to map industrial vessel activities and offshore energy infrastructure across the world's coastal waters from 2017 to 2021. We find that 72-76% of the world's industrial fishing vessels are not publicly tracked, with much of that fishing taking place around South Asia, Southeast Asia and Africa. We also find that 21-30% of transport and energy vessel activity is missing from public tracking systems. Globally, fishing decreased by 12 ± 1% at the onset of the COVID-19 pandemic in 2020 and had not recovered to pre-pandemic levels by 2021. By contrast, transport and energy vessel activities were relatively unaffected during the same period. Offshore wind is growing rapidly, with most wind turbines confined to small areas of the ocean but surpassing the number of oil structures in 2021. Our map of ocean industrialization reveals changes in some of the most extensive and economically important human activities at sea.

Small reductions in cargo vessel speed substantially reduce noise impacts to marine mammals.

Global reductions in the underwater radiated noise levels from cargo vessels are needed to reduce increasing cumulative impacts to marine wildlife. We use a vessel exposure simulation model to examine how reducing vessel source levels through slowdowns and technological modifications can lessen impacts on marine mammals. We show that the area exposed to ship noise reduces markedly with moderate source-level reductions that can be readily achieved with small reductions in speed. Moreover, slowdowns reduce all impacts to marine mammals despite the longer time that a slower vessel takes to pass an animal. We conclude that cumulative noise impacts from the global fleet can be reduced immediately by slowdowns. This solution requires no modification to ships and is scalable from local speed reductions in sensitive areas to ocean basins. Speed reductions can be supplemented by routing vessels away from critical habitats and by technological modifications to reduce vessel noise.

Impact of the COVID-19 pandemic on levels of deep-ocean acoustic noise.

The extraordinary circumstances of the COVID-19 pandemic led to measures to mitigate the spread of the disease, with lockdowns and mobility restrictions at national and international levels. These measures led to sudden and sometimes dramatic reductions in human activity, including significant reductions in ship traffic in the maritime sector. We report on a reduction of deep-ocean acoustic noise in three ocean basins in 2020, based on data acquired by hydroacoustic stations in the International Monitoring System of the Comprehensive Nuclear-Test-Ban Treaty. The noise levels measured in 2020 are compared with predicted levels obtained from modelling data from previous years using Gaussian Process regression. Comparison of the predictions with measured data for 2020 shows reductions of between 1 and 3 dB in the frequency range from 10 to 100 Hz for all but one of the stations.

Quarantine supervision of Wood Packaging Materials (WPM) at Chinese ports of entry from 2003 to 2016.

Exotic pests have caused huge losses to agriculture, forestry, and human health. Analyzing information on all concerned pest species and their origin will help to improve the inspection procedures and will help to clarify the relative risks of imported cargo and formulate international trade policies. Records of intercepted pests from wood packaging materials (WPM) from 2003 to 2016 in the China Port Information Network (CPIN) database were analyzed. Results showed that the number of intercepted pests from WPM was lowest in the first quarter and highest in the fourth one. The total number of interceptions increased each year, with 53.33% of intercepted insects followed by nematodes (31.54%). The original continent of most intercepted pests was Asia (49.29%). Xylophagous insects were primarily intercepted from Southeast Asian countries, whereas nematodes were primarily intercepted from Korea, Australia, Mexico, and other countries. WPM interception records were mainly concentrated in China's coastal inspection stations (98.7%), with the largest number of interceptions documented in Shanghai, followed by the inspection stations of Jiangsu Province. The proportion of pest taxa intercepted by the Chinese provinces' stations each year is becoming increasingly balanced. The number of pest disposal treatment measures for intercepted cargoes with dead non-quarantine pests increased significantly from 2012 to 2016. This reflects the fact that Chinese customs inspection stations are becoming increasingly scientific and standardizing the interception and treatment of WPM pests. The issues reflected in the database, with a view to providing a reference for future work by customs officers and researchers.

Tracking the global reduction of marine traffic during the COVID-19 pandemic.

The COVID-19 pandemic has resulted in unparalleled global impacts on human mobility. In the ocean, ship-based activities are thought to have been impacted due to severe restrictions on human movements and changes in consumption. Here, we quantify and map global change in marine traffic during the first half of 2020. There were decreases in 70.2% of Exclusive Economic Zones but changes varied spatially and temporally in alignment with confinement measures. Global declines peaked in April, with a reduction in traffic occupancy of 1.4% and decreases found across 54.8% of the sampling units. Passenger vessels presented more marked and longer lasting decreases. A regional assessment in the Western Mediterranean Sea gave further insights regarding the pace of recovery and long-term changes. Our approach provides guidance for large-scale monitoring of the progress and potential effects of COVID-19 on vessel traffic that may subsequently influence the blue economy and ocean health.

Mechanistic transmission modeling of COVID-19 on the Diamond Princess cruise ship demonstrates the importance of aerosol transmission.

Several lines of existing evidence support the possibility of airborne transmission of coronavirus disease 2019 (COVID-19). However, quantitative information on the relative importance of transmission pathways of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains limited. To evaluate the relative importance of multiple transmission routes for SARS-CoV-2, we developed a modeling framework and leveraged detailed information available from the Diamond Princess cruise ship outbreak that occurred in early 2020. We modeled 21,600 scenarios to generate a matrix of solutions across a full range of assumptions for eight unknown or uncertain epidemic and mechanistic transmission factors. A total of 132 model iterations met acceptability criteria (R2 > 0.95 for modeled vs. reported cumulative daily cases and R2 > 0 for daily cases). Analyzing only these successful model iterations quantifies the likely contributions of each defined mode of transmission. Mean estimates of the contributions of short-range, long-range, and fomite transmission modes to infected cases across the entire simulation period were 35%, 35%, and 30%, respectively. Mean estimates of the contributions of larger respiratory droplets and smaller respiratory aerosols were 41% and 59%, respectively. Our results demonstrate that aerosol inhalation was likely the dominant contributor to COVID-19 transmission among the passengers, even considering a conservative assumption of high ventilation rates and no air recirculation conditions for the cruise ship. Moreover, close-range and long-range transmission likely contributed similarly to disease progression aboard the ship, with fomite transmission playing a smaller role. The passenger quarantine also affected the importance of each mode, demonstrating the impacts of the interventions.

Sexually transmitted infections in seafarers: 2020's perspectives based on a literature review from 2000-2020.

BACKGROUND: Seafarers are a special population. The issue of sexually transmitted diseases among seafarers is as old as navigation itself, and is a public health issue and a matter of concern for seafarers themselves. The purpose of this article is to review the literature on sexually transmitted infections (STIs) in professional seafarers in the 21st century, with a view to guiding maritime physicians in their practice. MATERIALS AND METHODS: This is a Medline® and Scopus® literature review covering publications between 01/01/2000 and 31/12/2019. Out of the 224 articles, 26 were selected. RESULTS: This review showed that at the beginning of the 21st century, attention has been focused mainly on human immunodeficiency virus (HIV). Few seroprevalence data were available. Between 10% and 91% of seafarers had been tested for STIs. Several risk behaviours were identified: out of 4022 seafarers surveyed, 34.3% said they had several sexual partners; out of 3722 seafarers surveyed, 19.5% engaged with sex workers; out of 3493 seafarers surveyed, 63.3% did not always use condoms, while 58.0% were aware of the relevance of this protection. There was a lot of misunderstanding about STIs: 28.3% of seafarers believed that a healthy-looking person could not be HIV-positive. CONCLUSIONS: The main pathology studied was HIV. Many seafarers had no specific training and only learned about STIs and HIV through media such as television. Maritime doctors could use new technologies to disseminate the right information on STI prevention.

Research on anchor chain visualization for a ship anchoring simulation training system.

In the development of ship anchorage training systems, the problems of low efficiency and poor fidelity exist in the simulation of flexible anchor chains, and a position-based dynamics (PBD) method is proposed to express the chain movement. To satisfy the requirements of simulating anchoring manipulation, the PBD method modifies the position of anchor chain particles by controlling constraints. Using the original distance constraint and bending constraint of the PBD approach, two novel constraints, namely, the long-range attachment (LRA) constraint and pin constraint, are developed to simulate the bending and stretching of the anchor chain. Simulation of ordinary ropes can be achieved using distance and bending constraints. The developed LRA constraint is capable of preventing anchor chain particles from being overstretched. Adoption of the pin constraint is proposed to integrate two particles into one to be calculated as an attempt to simulate the connection between the chain and the anchor. The continuous collision detection (CCD) constraint method considering friction and viscosity is used to detect collisions in the ship anchoring training system. Collision detection covers chain collisions with other objects and chains. Finally, the PBD method is more efficient and robust than the Newton method. Since it has sufficient visual plausibility and can realize real-time visualization, the simulation system developed by the PBD method effective for training crew members.

The contribution of asymptomatic SARS-CoV-2 infections to transmission on the Diamond Princess cruise ship.

A key unknown for SARS-CoV-2 is how asymptomatic infections contribute to transmission. We used a transmission model with asymptomatic and presymptomatic states, calibrated to data on disease onset and test frequency from the Diamond Princess cruise ship outbreak, to quantify the contribution of asymptomatic infections to transmission. The model estimated that 74% (70-78%, 95% posterior interval) of infections proceeded asymptomatically. Despite intense testing, 53% (51-56%) of infections remained undetected, most of them asymptomatic. Asymptomatic individuals were the source for 69% (20-85%) of all infections. The data did not allow identification of the infectiousness of asymptomatic infections, however low ranges (0-25%) required a net reproduction number for individuals progressing through presymptomatic and symptomatic stages of at least 15. Asymptomatic SARS-CoV-2 infections may contribute substantially to transmission. Control measures, and models projecting their potential impact, need to look beyond the symptomatic cases if they are to understand and address ongoing transmission.

Turning the tide: reducing mortality among Danish merchant seafarers.

OBJECTIVES: While life at sea traditionally has presented a variety of potential hazards, rigorous measures have been taken in the past decades to ensure the safety and health of all aboard merchant ships. The aim of this study was to examine overall and cause-specific mortality among Danish seafarers in light of these changes. METHODS: A cohort of 44 555 male (75%) and female (25%) seafarers employed on Danish ships during 1986-1999 was established through records from the Danish Seafarer Registry. Subsequently, information on vital status and causes of death was linked to members of the cohort from the Danish Civil Registration System and the Danish Register of Causes of Death using unique personal identification numbers. Standardized mortality ratios (SMRs) were calculated for the seafarers using rates from a sample of the Danish employed population. RESULTS: Among seafarers with first employment prior to 1992, the overall mortality was high, with increases observed for many individual causes of death (overall SMR 1.78, 95% CI 1.72 to 1.83 for male seafarers; SMR 1.61, 95% CI 1.48 to 1.75 for female seafarers). Mortality among seafarers employed in the following period was reduced, with only a slight remaining excess of deaths. This excess in mortality was evident primarily among non-officers on board tankers and smaller ships. CONCLUSIONS: During recent decades, mortality among seafarers has changed, replacing the traditional image of a high-risk profession with almost normalised figures compared with the general working population. Marked imbalances in mortality according to job and ship categories have persisted though.

Clinical characteristics of the coronavirus disease 2019 (COVID-19) outbreak on a cruise ship.

BACKGROUND: A large COVID-19 outbreak occurred on the cruise ship Diamond Princess in February 2020. Little information has been reported about the clinical characteristics of the patients. METHODS: This single-center, retrospective, observational study was conducted in Yokohama, Japan. We included symptomatic patients who were infected on the ship and admitted to our hospital between 5 and 19 February 2020. All the cases were confirmed with SARS-CoV-2 infection by polymerase chain reaction (PCR). RESULTS: We confirmed 17 cases. The average age was 69 years; 10 patients were Asian and 7 were Caucasian. Eleven patients had one or more chronic diseases. The major symptoms were cough and fever. Chest computed tomography (CT) scans found bilateral ground-glass opacities predominantly in the peripheral area, which were similar to reports from cases in China. C-reactive protein (CRP) levels were higher in severe and critical cases than in mild to moderate cases. The moderate to severe cases reached symptomatic resolution; one of the three critical cases resulted in death due to multiple organ failure. SARS-CoV-2 was detected by PCR at an average of 7 days after symptomatic resolution. CONCLUSIONS: Cough and fever, increased blood CRP levels, and CT findings of bilateral ground-glass opacities predominantly in the peripheral lung were characteristic of the COVID-19 cases in this study. These findings were compatible with those of previous reports.

Exposure-response assessment of cancer mortality in styrene-exposed boatbuilders.

OBJECTIVES: To improve exposure estimates and reexamine exposure-response relationships between cumulative styrene exposure and cancer mortality in a previously studied cohort of US boatbuilders exposed between 1959 and 1978 and followed through 2016. METHODS: Cumulative styrene exposure was estimated from work assignments and air-sampling data. Exposure-response relationships between styrene and select cancers were examined in Cox proportional hazards models matched on attained age, sex, race, birth cohort and employment duration. Models adjusted for socioeconomic status (SES). Exposures were lagged 10 years or by a period maximising the likelihood. HRs included 95% profile-likelihood CIs. Actuarial methods were used to estimate the styrene exposure corresponding to 10-4 extra lifetime risk. RESULTS: The cohort (n= 5163) contributed 201 951 person-years. Exposures were right-skewed, with mean and median of 31 and 5.7 ppm-years, respectively. Positive, monotonic exposure-response associations were evident for leukaemia (HR at 50 ppm-years styrene = 1.46; 95% CI 1.04 to 1.97) and bladder cancer (HR at 50 ppm-years styrene =1.64; 95% CI 1.14 to 2.33). There was no evidence of confounding by SES. A working lifetime exposure to 0.05 ppm styrene corresponded to one extra leukaemia death per 10 000 workers. CONCLUSIONS: The study contributes evidence of exposure-response associations between cumulative styrene exposure and cancer. Simple risk projections at current exposure levels indicate a need for formal risk assessment. Future recommendations on worker protection would benefit from additional research clarifying cancer risks from styrene exposure.

Chronology of COVID-19 Cases on the Diamond Princess Cruise Ship and Ethical Considerations: A Report From Japan.

The Diamond Princess cruise ship has been anchored at the Yokohama port in Japan since February 3, 2020. A total of 691 cases of the coronavirus disease 2019 (COVID-19) infection had been confirmed as of February 23. The government initially assumed that the infection was not spreading aboard and therefore indicated that any persons who either tested negative for the virus or were asymptomatic should immediately disembark. However, on February 5, the government set a 14-day health observation period because of the severity of the infection. Passengers confirmed to be free from infection began disembarking on Day 15 (February 19) of the quarantine. The effectiveness and validity of infection control, justification for the timing of inspections, and even the nature of COVID-19 itself now are all in question. The ethical considerations related to cruise ship infection control include the reasonable justification for isolation, the psychological fragility and quality of life of the isolated passengers and crew members, the procedural justice inherent in a forced quarantine, and the optimization of control measures.The international coordination framework and the global ramifications of such outbreaks should be reevaluated by the international community. Denying a ship's entry based on local politics is incompatible with global justice. Events such as these require an international response and global regulations that seek to reduce disparities.

Suicide, fatal injuries and drowning among the crews of United Kingdom and Bermuda registered cruise and passenger ships from 1976 to 2018.

BACKGROUND: Little has been reported about mortality among crews in passenger shipping. The aim of the study was to determine the detailed causes and circumstances of deaths from unnatural causes among crews employed in United Kingdom (UK) and Bermudan registered passenger shipping, their trends, how they relate to the type of passenger ship and crew rank and to discuss preventative measures. MATERIALS AND METHODS: A longitudinal study from 1976 to 2018, based on reviews of marine accident investigation reports, death inquiry files, cruise shipping websites and online searches. RESULTS: One hundred and forty crew fatalities in UK (127) and Bermudan (13) passenger ships were identified: from accidents and drowning (91), suicides and disappearances at sea (38), homicide, other and unexplained causes (11). Over the 43-year study period, a reduction in mortality (per 1000 ship-years) from accidents and drowning was identified (mean annual reduction: 4.3%; 95% confidence interval: 2.1-6.5%) but no significant reduction for suicides and disappearances at sea (annual reduction: 1.2% confidence interval: -1.3% to +3.7%). Most suicides and disappearances (70%) were among customer service Staff and, of 19 employed on large cruise ships, most (79%) were non-Europeans. CONCLUSIONS: The number of suicides and probable suicides is a cause for concern, especially among customer service staff on cruise ships. These findings indicate the need for interventions to reduce suicide risks. Further studies are needed to improve the targeting of interventions. These will need both to analyse the circumstances of individual deaths and derive suicide rates according to rank, department and nationality, based on reliable population denominators.