1The imminent spread of infectious and contagious diseases within a ship has always been a cause of tension among sailors, and a challenge that is difficult to resolve for professionals of health control. It is a reason for tension among the crew because, being away from their homes, they fear becoming ill and not receiving appropriate specialized medical treatment. And it is also a challenge in the order of health control because the confinement, together with the high concentration of people in a single space, enhances the transmission of diseases among those on board, requiring strict control protocols by the health authorities and prevention programs by the cruise industry.
2Some people compare a ship with a “petri dish”, a cylindrical container used in the laboratory for the cultivation of microorganisms, since both would function as incubators for microbes and, therefore, ideal vehicles for the spread of diseases. It is not by chance that news of viral and bacterial diseases is frequently circulated in the mainstream media. Only among Brazilian crew members, we are aware of cases or outbreaks of scabies (G1, 2011), gastroenteritis (ANVISA, 2011), H1N1 (G1, 2012), measles (Viagem e Turismo, 2019) and, more recently, COVID-19.
3The articles read and cited here support the thesis that the confinement and concentration of people on cruise ships enhances the transmission of diseases. It cannot be said, therefore, that the shipowners were unaware of the imminent problem of contamination of some infectious and contagious disease, of any severity, between their passengers and crew. Unfortunately, an even more serious disease, discovered at the end of 2019, was found on several cruise ships in mid-February 2020. COVID-19 also reached the ships.
4The present study aims to present arguments on the possibility of contamination of crew and tourists through contagious diseases. The study also aims to analyze the prevention and management measures of the COVID-19 outbreak in Diamond Princess.
5The study is exploratory in nature and has a bibliographic review on the subject in the journals in the area of knowledge and National Health Surveillance Agency’ documents. The literature search was carried out from March to June 2020. This study uses the descriptive method and collaborates to understand maritime tourism.
6In international literature, we find specific articles in medical journals about the occurrence of communicable diseases, among passengers and crew, on cruise ships. Mouchtouri et al. (2010) cite the occurrence of outbreaks and/or infections in vessels by, especially, legionella, salmonella, escherichia coli, vibrio (bacteria) and norovirus, influenza A and B (virus). Pavli et al. (2016) state that the majority of infections registered on cruise ships are respiratory (29%) and gastrointestinal (10%).
7Fujita et al. (2018) analyzed the notifications, systematized by the National Health Surveillance Agency (ANVISA), of communicable diseases on board cruise ships on the Brazilian coast, in the period between 2009 and 2015. The analysis of the notifications indicate that norovirus was the main etiologic agent of the outbreaks of that period, although the rate of outbreaks has decreased over time. The authors conclude that the large number of passengers and crew confined to ships would be the main reason for the contamination. “This represents a high potential risk for the transmission of infectious diseases due to the confinement of these travelers in common spaces, with a high probability of exposure to fomites by the oscillation of the vessel” (Fujita et al., 2018: 11). They cite mini-cruises (that is, cruises with short routes of 3 to 4 days) as a problem for the control and supervision of epidemiological outbreaks, as it is common for communicable diseases to have an incubation time longer than the duration of the trip itself.
8Fernandes et al. (2014), in a study on the outbreak of Influenza B on a cruise ship off the coast of the state of São Paulo, in February 2012, concluded that crew members housed on the two lower decks were more likely to develop symptoms of illness similar to influenza (fever, cough, sore throat and dyspnea). The conclusion is related to confinement and the absence of air circulation, according to the authors.
The lower-ranking crew members were on such decks, usually sharing cabins that fit two to four people. There were no windows and circulated air came from air conditioners. The influenza virus is spread through droplets and aerosol from infected people when coughing and sneezing. Closed and crowded places, such as the ship’s lower decks, facilitate the spread of influenza virus (Fernandes et al., 2014: 301).
9Mitruka et al. (2012) explains that outbreaks on cruise ships of vaccine-preventable diseases, such as rubella, chickenpox and measles, are associated with the introduction and spread among crew members from countries with endemic transmission of these diseases, in addition to low rates of vaccination or not introduced or recently introduced the vaccine. Again, the confined and densely populated environment is cited as a facilitator of the transmission of contagious diseases, including vaccine-preventable diseases.
10Kak (2015) remembers that “an infectious agent introduced into the environment of a cruise ship has the potential to be distributed widely across the ship and to cause significant morbidity”. The infectious pathogens of potential risk in cruise ships can be, according to the author, gastrointestinal, respiratory and skin. One of the reasons for the high morbidity (rate of carriers of a certain disease in relation to the total population studied, in a given location and at a given time) within ships would also be related to the average age of passengers on ships, over 45 years old, and usually with chronic medical problems.
11Finally, we highlight the important research by Zheng et al. (2016) on the transmission of respiratory diseases on passenger ships. The authors begin the article by remembering that, although the voyage by ship supposes an outdoor experience, passengers and crew are mostly indoors, such as restaurants, theaters, dance halls and the cabins themselves. In addition, they share public bathrooms, the same food and drinks, as well as the same air conditioning system. Finally, they recall that approximately one third of passengers are elderly people, who are more susceptible to infectious diseases than the rest of the population.
12The authors state that outbreaks of respiratory diseases in passenger ships are aggravated by specific vulnerabilities of the ships, namely: a) a large number of people in close contact; b) duration of travel long enough to cover the period of virus transmission and incubation; c) diversity of people in the southern and northern hemisphere, where influenza vaccination may not be available during the disease season; and d) crew members can be continuous vehicles for transmitting the virus, as infections can remain on board a cruise from one trip to the next (Zheng et al., 2016).
13The results of the study by Zheng et al. (2016) point out that the risk of infection by a crew member is higher than the risk of a passenger, because the crew member has contact with all the groups of the ship. They also indicate that the use of face masks by crew members serving in restaurants, bars or lounges, as well as the increase in the rate of air exchange in some or all locations on the ship, resulted in a moderate reduction in the rate of respiratory disease transmission. The most effective measure for reducing the transmission rate was the installation of high efficiency air filters and devices for germicidal ultraviolet irradiation in the ship's ventilation systems.
14The articles cited in this introduction suggest that the prevention of communicable diseases on board ships necessarily involves:
-
Strictness with sanitary conditions and sanitary control measures in ports and ships;
-
Vaccination requirement for diseases preventable by vaccination between passengers and crew;
-
Quarantine imperative for sick passengers and/or crew members, who must remain isolated in their cabins to avoid contagion among other passengers;
-
Use of face masks and incentive to respiratory hygiene and cough etiquette;
-
Installation of high efficiency air filters and germicidal ultraviolet irradiation devices in the ship's ventilation systems.
15All the articles cited support the thesis that the confinement and concentration of people on cruise ships enhances the transmission of diseases. It cannot be said, therefore, that the shipowners were unaware of the imminent problem of contamination of some infectious and contagious disease, of any severity, between their passengers and crew. Unfortunately, an even more serious disease, discovered at the end of 2019, was found on several cruise ships in mid-February 2020. COVID-19, which spread to 188 countries and regions, has been diagnosed in more than 21 million of people and killed more than 70 thousands of people worldwide, according to monitoring by Johns Hopkins University (August 20th), also reached the ships.
16COVID-19, a disease caused by the SARS-CoV-2 coronavirus, was discovered on December 31, 2019 after cases registered in Wuhan (China). On March 11, 2020, the World Health Organization (WHO) started to characterize it as a pandemic, due to the alarming levels of spread and severity of the disease, having reached almost all countries in the world. The danger of the disease is related to its high contagion power, even among asymptomatic infected people. The high transmissibility of the disease is even greater in confined spaces, according to Mizumoto & Chowell (2020), including hospitals, prisons, churches and, of course, cruise ships.
17Between March 9 and 26, all major cruise lines suspended operations, voluntarily and temporarily, across their entire fleet. The main reasons for the downtime would have been: to avoid contagion of the new coronavirus between crew and passengers, in addition to the sudden drop in demand and operational instability (World Cruises, 2020a).
18However, most companies were slow to suspend operations in a few days, or even weeks, after the WHO statement that characterized the disease as a global pandemic. Images circulated on social networks and international newspapers: crew members working in the second half of March, when the disease was already present in almost the entire globe - on March 11, the date of the WHO declaration, there were 125 thousand people infected; on March 26, the date on which the last shipowner suspended its operations, the number more than quadrupled, from 529 thousand contaminated.
19Table 1 shows the exact days when cruise ship operations are suspended. These are dates on which new passenger shipments were no longer carried out, and in several cases, the last passengers had to stay and carry out social isolation on board. That is because, in mid-March, countries like the United States of America, Canada, New Zealand and Australia banned passenger ships from docking at their ports, as required by local health control agencies.
Table 1. Suspension of operations by shipowners
Suspension of operations
|
Shipowner
|
9/March
|
Costa Cruises
|
12/March
|
Princess Cruises
Viking Cruises
|
13/March
|
Azamara Cruises
Celebrity Cruises
Cruise and Maritime Voyages
Holland America
Silversea Cruises
|
14/March
|
AIDA Cruises
AmaWaterways
American Cruise Lines
American Queen Steamboat Company
Arosa Cruises
Avalon Waterways
Carnival Cruise Line
Celestyal Cruises
Crystal Cruises
Cunard
Disney Cruise Line
Emerald Waterways
Marella Cruises
MSC Cruises
Norwegian Cruise Line
P&O Cruises
Seabourn Cruises
Uniworld
Windstar Cruises
|
15/March
|
Bahamas Paradise Cruise Line
Oceania Cruises
Ponant Cruises
Pullmantur
Royal Caribbean
|
16/March
|
Lindblad Expeditions
|
18/March
|
Hapag-Lloyd Cruises
|
23/March
|
TUI Cruises
UnCruise Adventures
|
26/March
|
Virgin Voyages
|
Source: Cruise Mapper (2020).
20The Zaandam ship, from Holland America company, for example, faced an emergency situation on board, with just over 100 shipped people with symptoms similar to those of COVID-19. The ship was in the Pacific Ocean and intended to cross the Panama Canal to land passengers on the east coast of the United States of America. Panamanian health control bodies, however, did not allow the ship to transit through the canal, only allowing the transfer of healthy passengers from Zaandam to another ship of the same company (World Cruises, 2020b).
21Several ships, such as the Costa Deliziosa, the MSC Magnifica and the Pacific Princess, remained in operation for weeks and even months, awaiting authorization to dock. On June 8, the Artania, the last cruise ship in operation, finally made its final stopover at the port of Bremerhavan (Germany), after six months of sailing (CNN, 2020).
22Unfortunately, the new disease was seen on several cruise ships as early as mid-February 2020. It is reported that more than 3,200 people (including passengers and crew) were infected with COVID-19 inside the ships, of which more than 70 died (Cruise Mapper, 2020). In image 1, it is possible to verify the mapping, carried out between January and March 2020, of cruise ships with cases of COVID-19.
Image 1. Cruise ships with cases of COVID-19 (January to March 2020)
Source: CDC (2020).
23An expressive number of cases/outbreaks by the disease have been recorded on several cruise ships around the world. Table 2 shows the number of positive tests for the new coronavirus among crew and passengers per ship, including the number of deaths.
Table 2. Cases/outbreaks of contamination by the new coronavirus
Shipowner
|
Ship
|
Location
|
Positive tested
|
Death
|
Aurora Expeditions
|
Greg Mortimer
|
Argentina
|
165
|
1
|
Celebrity Cruises
|
Celebrity Apex
|
France
|
224
|
0
|
Celebrity Eclipse
|
USA
|
68
|
3
|
Celebrity Galapagos
|
Ecuador
|
48
|
0
|
Celebrity Infinity
|
USA
|
3
|
1
|
Celebrity Solstice
|
Australia
|
20
|
1
|
Costa Cruises
|
Costa Atlantica
|
Japan
|
149
|
0
|
Costa Fascinosa
|
Brazil
|
43
|
3
|
Costa Favolosa
|
Dominican Republic
|
13
|
1
|
Costa Luminosa
|
Atlantic Ocean
|
94
|
3
|
Costa Magica
|
Guadeloupe
|
10
|
0
|
Costa Victoria
|
Italy
|
1
|
0
|
Cunard
|
Queen Mary 2
|
South Africa
|
1
|
0
|
Disney Cruise Line
|
Disney Wonder
|
Panama
|
47
|
0
|
Fred Olsen
|
Black Watch
|
Scotland
|
10
|
0
|
Braemar
|
Caribbean
|
5
|
0
|
GHK Dream Cruises
|
World Dream
|
South China Sea
|
12
|
0
|
Holland America
|
Zaandam
|
Pacific Ocean
|
14
|
4
|
Marella Cruises
|
Marella Explorer 2
|
Caribbean
|
23
|
1
|
MSC Cruises
|
MSC Bellissima
|
United Arab Emirates
|
5
|
0
|
MSC Fantasia
|
Portugal
|
1
|
0
|
MSC Opera
|
Italy
|
8
|
0
|
MSC Preziosa
|
Bahamas
|
2
|
0
|
MSC Splendida
|
France
|
1
|
0
|
NCL
|
Norwegian Bliss
|
USA
|
1
|
0
|
Norwegian Breakaway
|
Caribbean
|
3
|
0
|
Norwegian Gem
|
Bahamas
|
2
|
2
|
NCL America
|
Pride of America
|
Hawaii
|
7
|
0
|
Phoenix Reisen
|
Artania
|
Australia
|
89
|
4
|
Princess Cruises
|
Coral Princess
|
Barbados
|
82
|
0
|
Diamond Princess
|
Japan
|
712
|
14
|
Grand Princess
|
USA
|
132
|
7
|
Ruby Princess
|
Australia
|
852
|
22
|
Pullmantur
|
Horizon
|
United Arab Emirates
|
125
|
0
|
Royal Caribbean
|
Adventure of the Seas
|
Jamaica
|
19
|
0
|
Jewel of the Seas
|
United Arab Emirates
|
2
|
0
|
Liberty of the Seas
|
USA
|
2
|
0
|
Oasis of the Seas
|
Bahamas
|
17
|
1
|
Ovation of the Seas
|
Australia
|
111
|
0
|
Symphony of the Seas
|
Bahamas
|
32
|
1
|
Voyager of the Seas
|
Australia
|
40
|
1
|
Silversea
|
Silver Explorer
|
Chile
|
1
|
0
|
Silver Shadow
|
Brazil
|
2
|
1
|
TUI
|
Mein Schiff 3
|
Germany
|
9
|
0
|
Source: Cruise Mapper (2020).
24As shown in the spreadsheet, the two largest coronavirus outbreaks occurred on the Ruby Princess ships (March | Australia) - 852 infected, 22 deaths and Diamond Princess (February | Japan) - 712 infected, 14 deaths. Although the outbreak of COVID-19 contamination at Ruby Princess was the largest recorded in absolute numbers, the extensive literature of articles in international journals of infectology on COVID-19 outbreaks on ships gives greater prominence to the Diamond Princess, both because it was where the first outbreak happened, and also because it was the only one where it was possible to map the origin and evolution of the contamination, still inside the ship.
25Coincidentally (or not), these outbreaks occurred on ships owned by Princess Cruises. Since 2003, the Princess has been part of the Carnival Corporation group, headquartered in the United States of America. The owner has 18 ships, most of which are registered in the Bermuda Islands (North Atlantic). On May 15, the Princess Cruises announced dismissals, licences and wage and salary reductions for 50% of its workers in the cities of Santa Clarita (California) and Seattle (Washington), located on the west coast of the United States of America, due to the economic impacts generated by the pandemic (The Signal, 2020).
26A significant number of cases and outbreaks of the new coronavirus has been recorded around the world. Among them, the biggest outbreaks happened on the Ruby Princess and Diamond Princess cruise ships. Although the outbreak of COVID-19 contamination in Ruby Princess was the largest recorded in absolute numbers (852 infected and 22 deaths), the extensive literature of international infectology journals’ articles about the COVID-19 on cruise ships gives more emphasis to the Diamond Princess, where the first outbreak happened, and also the only one in which it was possible to trace the origin and evolution of the contamination.
27The Diamond Princess cruise ship departed on January 20, 2020, from Yokohama (Japan), for a tour through Southeast Asia. The trip included stops in China, Vietnam and Taiwan (image 2). Five days later, on January 25, a passenger with symptoms of COVID-19 disembarked in Hong Kong, but the ship's operations continued. The ship returned to Japan only in the first days of February, when the first disembarked passenger had his test for COVID-19 confirmed. The ship remained in Yokohama for the following weeks.
Image 2. Itinerary of Diamond Princess ship from January 20 to February 4
Source: Nakazawa et al. (2020)
28In Japan, the ship was already quarentined when tests were performed among symptomatic people on board, and positive testing for the new coronavirus was growing exponentially (see on image 3 the period between the 5th and 24th of February). Dahl (2020) estimates that, at the time, the ship may have had the highest concentration of cases outside mainland China. Also, according to John Hopkins University monitoring, the ship presented more contaminated people than other countries’ numbers of cases in August 20th, being ahead of Taiwan, Cambodia, Timor-Leste, Monaco, Guyana, and others.
Image 3. Cummulative number of confirmed cases on Diamond Princess
Source: CDC (2020).
29Altogether, it was registered that 19.2% of the Diamond Princess’ embarked people were contaminated by the new coronavirus. Of the 712 who tested positive for SARS-CoV-2, 331 (46.5%) were asymptomatic at the time of testing. Among the symptomatics, 37 (9.7%) required intensive care (Moriarty et al., 2020). The cases were verified among people from 28 different nationalities, with emphasis on the Japanese (42%), Americans (13%), Chinese (9%), Filipinos (8%), Canadians (8%) and Australians (7%) (Mizumoto et al., 2020).
30According to Takeuchi (2020), passengers and crew members who needed hospitalization were admitted to the emergency medical facilities of Yokohama City (Japan). Some patients with stable respiratory condition at the time of disembarkation had their health gradually deteriorated, requiring lung ventilators and extracorporeal membrane oxygenation (ECMO).
31Nishiura (2020) estimates that the peak of the transmission occurred between February 2 and 4 and that the estimated number of new infections among passengers without close contact after February 5, when quarantine was imposed on the ship, was quite small, reaching a maximum of one case of infection per day from February 8 to 10. That’s why the author states that the policy of restricting circulation within the ship has succeeded in significantly reducing the number of secondary transmissions on board. Most deaths were recorded, according to Russell et al. (2020), between February 21 and March 2.
32The Japanese government's decision to keep passengers quarentined on board for fourteen days, from February 5 to 19, instead of disembarking and repatriating them immediately, was intended to protect the population on land, regardless of the consequences for those on board (Dahl, 2020). Takeuchi (2020), a physician at Yokohoma University's Emergency Medical Department, said in mid-February that nine (9) emergency medical centers in the city were already occupied with Diamond Princess passengers, so "This is one of the greatest concerns regarding the future increase in the number of patients from the City" (Takeuchi, 2020: 3).
33Nakazawa et al. (2020) present a reflection about the quarantine imposed by the Japanese government to the people on board of the Diamond Princess. The authors understand that there has been an ethical dilemma between imposing isolation on the ship and accepting the disembarkation of passengers for treatment or isolation on land. "The dilemma between isolation and human rights is a classic and fundamental issue in public health ethics, and, thus, it is difficult to propose concrete arguments that solve the dilemma completely" (Nakazawa et al., 2020: 4). They conclude by stating that decision-making must take into account the geopolitical considerations and agreements and the availability of medical resources and health facilities to care for those infected.
34Sawano et al. (2020) believe that the quarantine imposed was a mistake for three main reasons: 1) It was not effective enough to avoid spreading the virus in Japan, since there were already cases of infected people in its territory before the arrival of Diamond Princess; 2) It may have contributed to accelerate the contagion of the virus among the ship’s passengers and crew; and 3) The medical and psychological care for passengers and crew was unsatisfactory, especially taking into account that most of the them were elderly, with more than 200 people over 80 years old.
35In fact, the outbreak on the Diamond Princess ship caught the attention of infectologists from all over the world, who made harsh criticisms about the outbreak’s prevention and management measures (The Asahi Shimbun, 2020). The international press highlighted the criticism of Kentaro Iwata, a professor in the infectious diseases division of the Kobe University Hospital (Japan), who declared in an internet video, deleted soon afterwards its publication, that there was no clear separation of uncontaminated "green zones" from potentially dangerous "red zones" inside the ship (The Japan Times, 2020).
36The literature notes also came in the same direction. In table 3, we present the main arguments.
Table 3. Verified problems in the prevention and management measures of the COVID-19 outbreak in Diamond Princess
Verified Problems
|
Argumentation
|
Delay to act
|
The crowd infection percentage would be controlled effectively if the recommended or mandatory measures can be taken immediately during the alert phase of COVID-19 outbreaks (Fang, 2020: 2).
|
Not isolating the crew from the beginning of quarentine
|
Failing to isolate the crew of the Diamond Princess from the beginning of the quarantine likely contributed to further virus transmission to passengers and crew during the quarantine time and made it necessary to subject the remaining crewmembers to another full quarantine period ashore after all passengers had debarked (Dahl, 2020: 7).
|
Disregard for asymptomatic contaminated crew members
|
Crew members continued to perform service unless they showed symptoms. […] These groups contain “silent carriers” which include the pre- and asymptomatic infected population and may be a major force in the COVID-19 pandemic. We suggest, with due caution, that it may be necessary to develop stronger protocols to address these cases, especially in confined spaces, in order to successfully control the spread of the virus (Huang, 2020: 7).
|
Exceptions to separation between infected areas and non-infected areas
|
Theoretically, we needed to divide the traffic line between infectious (red zone) and noninfectious things (green zone) including humans, but exceptions were made (Yamahata & Shibata, 2020: 4).
|
Several problems in the management of transportation and allocation of patients in the city and surrounding’s medical centers
|
On the peak day, we had new 99 RT-PCR–positive patients, and we had to transport family members separately, even though they should have stayed in the same facility (Yamahata & Shibata, 2020: 5).
Some people who were transported from the ship to the Okazaki facility developed mild chest pain during the 6-hour transportation. Based on the results of the CT image, the development of pneumonia may cause pleural pain. The speed at which the patients changed from being asymptomatic or mild to severe was very high. About 10% of asymptomatic people developed symptoms during a 6-hour transport, and 10%-20% of them worsened rapidly to a state in which intubation was considered within 24 hours (Yamahata & Shibata, 2020: 5).
|
Disorderly disembarkation of passengers
|
Unlike the usual disembarkation from a cruise ship, the patients needed to carry their baggage themselves. They had to pass through the quarantine area and customs. Some people had difficulty walking or had a lot of baggage, which meant it took a long time to move. [...] Many foreign passengers did not understand Japanese or English at all, making the situation unimaginably difficult to manage (Yamahata & Shibata, 2020: 6).
|
Difficulty feeding passengers during quarantine
|
We needed to support the daily lives of 3711 people on the ship. Since all passengers were isolated in each cabin, we had to deliver daily supplies to each room. There were people of various nationalities and religions aboard, and it was necessary to consider religious taboos and allergies. The crew members had to keep working under the risk of infection (Yamahata & Shibata, 2020: 6).
|
Source: Fang (2020), Dahl (2020), Huang (2020), Yamahata & Shibata (2020).
37We recall that the academic literature about the occurrence of communicable diseases on cruise ships has been privileging the focus on the passengers, or even on all the embarked, indiscriminatedly. Regarding the outbreak of COVID-19 in the Diamond Princess, we found only two papers that specifically refer to the contamination among the crew (Moriarty et al., 2020; Kakimoto et al., 2020). Even so, it was not possible to find any official data on the amount of contaminated crew members among the 712 confirmations, as well as on the amount of deceased crew members among the 14 recorded deaths.
38Moriarty et al. (2020) describe the profile of the total Diamond Princess workers, 1,045 crew members. On average, they were 36 years old; they were from 48 different nationalities: 51% from the Philippines, 13% from India, 7% from Indonesia and 29% from other countries; 81% of them were men and 19% were women.
39Kakimoto et al. (2020) presented in their paper an initial investigation about the transmission of the new coronavirus among the crew members during the quarantine of the Diamond Princess ship. The first confirmed case was a crew member from the food sector who presented a fever on February 2, and, after laboratory confirmation, was released for treatment on land. Until the end of the first week of February, only the crew members who sought the ship's medical assistance presenting COVID-19 similar symptoms had access to laboratory testing. From that day on, many other cases were confirmed among the crew.
40It was found that, at the time of the investigation, 15 of the 20 confirmed cases occurred among food service workers who prepared food for other crew members ("crew mess") and passengers; and 16 of the 20 confirmed cases occurred among the cabins on Deck 3, the floor where the food service workers lived.
These interviews indicated that infection had apparently spread among persons whose cabins were on the same deck and who worked in the same occupational group, probably through contact or droplet spread, which is consistent with current understanding of COVID-19 transmission (Kakimoto et al., 2020: 312).
41The data presented in the article confirm the thesis that the transmission of the disease is related to the fact that ships brings a large amount of people together into confinement.
42The authors Mizumoto et al. (2020) point out that the transmission of the new coronavirus (whose power of contagion is high, especially in confined spaces) on cruise ships, and especially on the Diamond Princess, could have been mitigated if there wasn't a high concentration of people. "To further mitigate transmission of COVID-19 and bring the epidemic under control in areas with active transmission, it may be necessary to minimise the number of gatherings in confined settings" (Mizumoto et al., 2020: 4).
43The analysis presents data on the contamination that occurred on the ship Diamond Princess and how some consequences could have been avoided if the measures taken had been taken more quickly and urgently. It also shows the importance of having alternatives when emergencies arise, through transnational agreements on the route. The contamination of passengers shows that the transmission of COVID-19 affected older populations. The identification of problems (Fang, 2020; Dahl, 2020; Huang, 2020; Yamahata & Shibata, 2020) that have arisen in the case of the Diamond Princess Ship shows that some security measures may be present in new rules that regulate maritime tourism.