[Answer] How To ‘Track Trace Treat’ Suspected COVID Cases in a Ship?


As the pandemic deepened it has become crucial to properly track, trace and treat covid19 patients, especially in a ship. let’s take a look how you can do that with a European Commission Guidelines

Case management on board

During the cruise, if a passenger develops symptoms compatible with COVID-19 while on board, the following steps should be taken for this passenger:

 they should be instructed to wear a medical face mask (if not already wearing one);
 they should be isolated in an isolation ward, cabin, room or quarters and infection control measures should be instituted until arrival at the closest destination port where testing for COVID-19 can be performed;
 a limited number of crew members (wearing appropriate PPE) should be assigned to serve this cabin(s);
 if more than one person onboard the cruise ship exhibits COVID-19 compatible symptoms requiring testing, and if there is not enough capacity to isolate in single-occupancy cabins, quarters, etc then cohorting can be considered until arrival at the closest destination port where testing for COVID-19 can be performed.

In the event that a possible, or probable or confirmed case of COVID-19 is identified on board, the ship should be diverted to the nearest port where testing for SARS-CoV-2 can take place and where local public health authorities can be consulted to further manage the situation including the provision of specialist care, and where necessary, carrying out contact tracing.

Passenger locator data

The current standard for collecting passenger locator data is a form that was developed as a collaboration between WHO, the International Civil Aviation Organization (ICAO) and the International Air Transport Association (IATA) in 2012 for the aviation sector. Passenger locator forms can be used for any conveyance and for the maritime industry a modified form has been developed addressing both passengers and crew by the EU-Joint action Healthy Gateways.

Depending on the public health regulations in the destination country(-ies) passengers can be asked to fill out a hard copy of passenger locator form before entering the cruise ship, before visiting destination ports and/or before disembarking the cruise.

The same forms can be used for the cruise ship crew particularly if a change of crew is foreseen. Passenger locator data should be made available to the public health authorities as soon as possible upon their request so that they can initiate contact with exposed passengers.

The prompt availability of accurate passenger locator data is extremely important for the success and effectiveness of contact tracing operations (see section below). This enables public health authorities to identify and notify contacts of an infected case for active follow-up and the provision of relevant advice.

Direct collaboration between cruise companies, port authorities and public health authorities would be the easiest way to obtain the necessary passenger data in a timely manner for effective contract tracing. Member States will need to assess whether the
transfer of passenger location data from cruise ships to public health authorities complies with the requirements under the General Data Protection Legislation (GDPR), taking into account the legal requirements under their national law.

ECDC has proposed collecting a minimum data set, which allows the rest of the personal information to be obtained during the contact tracing interview. This data includes the following limited fields:
 Cruise ship name and number, Cabin number;
 Full name
 Date of birth (optional, but may be useful to differentiate between people with common names);
 Telephone number: a functioning mobile number preferred;
 Email address: a functioning email.

Electronic methods for transferring these data should be explored in collaboration with the cruise companies and port authorities

Contact tracing

Contact tracing is an essential measure to limit the spread of COVID-19. It is normally done only when a case has been laboratory-confirmed but in the cruise ship setting it is recommended that contact tracing is initiated already when a possible or probable case of COVID-19 is identified and while waiting for laboratory confirmation.

This is due to the high risk of transmission on cruise ships and the fact that rapid tests, while available, are currently not validated and confirmatory testing is likely to only be available on shore. In this section, the word ‘case’ includes possible, probably and confirmed cases.

ECDC guidance on contact tracing70 as well as WHO guidance ‘Operational considerations for managing COVID-19 cases or outbreaks on board ships’ should be consulted when planning for how to carry out contact tracing. Contact tracing should always be done in collaboration with public health authorities.

If the ship is not yet in port, and a possible case has been identified, crew should start contact tracing on board while also contacting with public health authorities in the next port to ensure their input into the contact tracing process.

ECDC guidance on contact tracing defines high-risk and low-risk exposure contacts and gives advice for follow up.

All persons on board should be assessed for their exposure and classified as high risk exposure (close) or low risk exposure contacts. The passenger or crew member that meets the definition of a case should be asked to provide information about the places that he/she visited and about his/her contacts, including the period from two days before the onset of symptoms on board the ship or ashore.

Two different definitions of contacts should be used depending on the number of cases identified on board:

A: If a single possible or probable case OR a couple of possible or probable cases sharing the same cabin have been identified on board, then the following definitions of contacts should be applied:

High risk exposure (close) contact:
 A person who has stayed in the same cabin with a case;
 A cabin steward who cleaned the cabin of a case or who delivered food to the cabin where the case was staying.
 A person who has had face to face contact (on-board or on-shore) within 2 metres for more than 15 minutes or who was in a closed environment for more than 15 minutes with a case. For passengers this could include but is not limited to participating in common activities, participating in the same immediate travelling group, or taking a class as well as
sharing the same social space such as restaurant or gym. This also includes intimate partners. For crew this mayinclude working in the same area as a case or socialising with a case (including fellow crew members), waiting on atable where a case was dining or leading a social activity where the case was participating.
 Healthcare worker or other person providing direct care for a case without wearing appropriate PPE.

Low risk exposure contact:
 In a confined space such as a cruise ship where it is difficult to assess the contact exposure, it is advised to consider as low-risk exposure contacts all travellers on board the ship who do not fulfil the criteria for the definition of a close contact.

B: If a single confirmed case OR more than one possible or probable case not sharing the same cabin have been identified, all travellers on board should be considered as high-risk exposure contacts. However, this may be modified depending on the risk assessment of individual cases and their contacts conducted by the public health authorities.

Note that the assessment of whether persons are high- or low-risk exposure contacts should be done in conjunction with public health authorities and a case-by-case assessment of risk should always be made.

Management of contact persons

Contacts of possible and probable cases should be managed as if the case was confirmed until the final test result is available.

If the possible case tested negative no further action is needed. If the laboratory result is positive, contacts should be managed as detailed below and according to the ECDC guidance on contact tracing which outlines this in more detail.

High-risk exposure contacts should quarantine for a period of 14 days after the last exposure to the case. They should strictly follow hygiene measures and respiratory etiquette, monitor for symptoms, ideally be provided with a fever thermometer, and be
informed on what to do if they develop symptoms.

Quarantine should ideally happen in an on-shore facility, but if not possible then contacts should remain in their cabin with the door closed and provided with food and other essentials, while ensuring the safety of crew providing these services, considering
also that passengers could be provided with cleaning materials to clean the cabin, rather than cleaning being done by crew who would then be risk exposed. Cabins where contacts are quarantined should have ensuite bathrooms. If two or more people share a cabin and only one of them is a high-risk contact, the contact person should be relocated to a single-occupancy cabin.

If two or more people who are identified as contacts share a cabin, and one develop symptoms the person who develop symptoms should be managed as a possible case and their contact persons should be subsequently housed in separate cabins.

If the cruise comes to an end during the 14-day period, contact persons should be safely disembarked and quarantine continued onshore.

Testing should also be considered for high risk exposure (close) contacts even if they have not developed symptoms. The prompt identification of infection among contacts would enable tracing of their contacts to be initiated as early as possible rather than waiting for symptoms to develop. In particular, contacts at risk to develop severe disease (e.g. elderlies and/or people with underlying conditions and co-morbidities) should be actively tested. A negative PCR test result for SARS-CoV-2 is not a substitute for the 14-day quarantine period as infection may develop later in the incubation period after an initially
negative test.

Low-risk exposure contacts should be provided with detailed information on daily self-monitoring for COVID-19-compatible symptoms for 14 days following the last exposure to the case; physical distancing measures; rigorous hand hygiene and respiratory etiquette measures, including wearing a face mask. Should symptoms develop, these contact persons should immediately self-isolate and seek medical advice. This applies whether the contact persons remain on board or have disembarked. All low-risk exposure contacts should be requested to complete passenger locator forms with their contact details
and the locations where they will be staying for the following 14 days.

If one of the contact persons develops symptoms contact tracing should start again and identify their contact persons who should be managed accordingly.

A database on cases and their contacts should be kept on board. For large number of cases WHOs software Go. Data could be used.

Cases identified after the end of the cruise

It is also important to rapidly identify and trace the contacts of anyone who, after the end of their time on the cruise ship is diagnosed with COVID-19 and is determined to have been infectious while on the ship (with the infectious period starting from 2 days before symptom onset). Contact tracing should be initiated by the public health authorities where the case is diagnosed, and the cruise ship company would be contacted to help facilitate identifying and contacting passengers and crew who were exposed to the case. Measures to assist and facilitate such tracing could be as simple as asking passengers to provide contact
details for follow-up if required. Collection of contact information should ideally be done electronically to facilitate and speed up the process of contacting persons at risk and for merging this information with the contact tracing database.

Please note that the identification of a single confirmed case that was infectious on the cruise (from two days before symptom onset) results in all passengers and crew who were on board at the time being considered high-risk contacts (as per the definition above).

All passengers should therefore be contacted and informed about management including quarantine for 14 days since last exposure as outlined above.

They should also be advised to contact the public health authorities where they are staying for further advice on follow up

Immunity certificate

The quantity, quality and duration of the human immune response to SARS-CoV-2 is, as yet, unclear. In addition, we lack validated serology tests that can ascertain immunity to the virus. Therefore, there is not enough evidence about the effectiveness of antibody-mediated immunity to guarantee the accuracy of an immunity passport / certificate.
Given the evidence currently available, any immunity certification for COVID-19 is not supported by ECDC.

Requirement for recent negative RT-PCR test for COVID-19

If a COVID-19 RT-PCR test performed using a well-validated diagnostic molecular detection assay is negative (e.g. 72 hours prior to departure), it could indeed help to prevent asymptomatic and pre- symptomatic COVID-19 cases from travelling.

However, a negative test does not exclude the possibility that the person tested may become infectious in the days prior to departure (after the test has been performed) or during travel (on board, or at the destination) since the virus incubation period is 2-14 days.

All testing should take into account the quality of the test and specimen, as well as the epidemiological situation to exclude the possibility of a false result.

If a national authority or a cruise operator decides to include laboratory testing (e.g. a RT-PCR for COVID-19 before departure) as part of the exclusion policy for travellers, this should be communicated to passengers well before their departure date, so that they have sufficient time to plan testing. When deciding whether to include testing as a requirement for travel, EU Member States should take into consideration the limitations, including cost, testing policy and the availability of tests in the other EU/EEA countries.

In many of the EU/EEA Member States, testing is not readily available or foreseen for asymptomatic persons or for those with mild respiratory symptoms. Finally, the 72-hour window may cause significant logistical issues, due to the laboratory processing time required between sample collection and results becoming available.

Temperature screening

Temperature screening of passengers, particularly at international points of entry (PoE), is frequently considered as the go-to measure to implement for health safety in order to safeguard regions or countries from the introduction of a communicable disease. These procedures usually include some type of thermal screening (contactless thermometers, thermal scanners/cameras and others) to detect exiting or entry passengers with fever (e.g. body temperature >38°C). Additional (secondary) screening is frequently added to this procedure using a health declaration form or a health questionnaire, potentially administered and assessed by a health professional to determine the need to test for the particular pathogen.

Historically, reports reviewing entry screening procedures based on temperature screening from several countries at the time of the SARS outbreak (2003), the A(H1N1)pdm09 influenza pandemic (2009) and the Ebola virus disease (EVD) in West Africa
(2014-2016) consistently show that screening using temperature control is a high-cost, low-efficiency measure.

As regards COVID-19, based on what we know so far, several of its characteristics make it unlikely that temperature screening alone, either at the start of the cruise or as a daily health monitoring tool will be an effective and/or efficient procedure to
promptly detect COVID-19 on board. Moreover, it is also unlikely that temperature screening will prevent the introduction and onward transmission of the disease in destination ports.

These assessments are based on the following:
 Many individuals who have been infected with the virus could be in the incubation phase when travelling and not yet showing symptoms; SARS-CoV-2 has an incubation period of 2-14 days, with 75% of cases developing symptoms after 4-7 days. Passengers in the incubation period will not be detected by temperature screening, even in a scenario assuming high sensitivity equipment. When this scenario was modelled for entry or exit screening at the beginning of the outbreak in January 2020, it showed that an estimated 75% of infected passengers would exit or enter the country without being detected.

 Since the beginning of the pandemic, evidence has accumulated indicating that asymptomatic (or pre-symptomatic and mild) cases play a significant role in the transmission of COVID-19 (maybe up to 40%) and it is currently established that transmission starts before the onset of symptoms (peaking 0.7 days before).75

 In the case of COVID-19, fever is frequently, but not consistently, reported in symptomatic cases. According to ECDC’s weekly epidemiological report for week 26/2020, fever was reported for 53% of over 160 000 laboratory-confirmed COVID-19 cases
entered in The European Surveillance System (TESSy).76 In addition, fever is a symptom that can be temporarily concealed by using antipyretic drugs.

The large variety of screening equipment (contactless thermometers, thermal scanners, etc.) commercially available requires that particular care is taken in calibration and the setting of thresholds for categorising people as screen-positive. The performance of
devices is difficult to compare because of different targets and modes of operation. In addition, their performance is affected by the choice of the cut-off value set for screening (e.g. 37.5 or 38.0°C).

In general, performance is reported as follows:
o Sensitivity: 80–99%, meaning that between 1 and 20% of febrile passengers will not be detected (false negative).
o Specificity: 75–99%, meaning that between 1 and 25% of non-febrile passengers will be incorrectly detected (false positive).

Some reports suggest that taking the average of several readings improves accuracy; however, this increases the resources necessary to perform the task.

Nevertheless, temperature screening processes may help dissuade those who are sick from travelling or entering public places and enhance the confidence of healthy travellers. In addition, they offer a further means for providing specific information to passengers on the disease, the current epidemiological situation and where to seek medical advice, if needed.

A number of imported COVID-19 cases have been detected through temperature and entry screening at destination PoE (e.g. in Taiwan, where there is a permanent screening system in place).

Due to the currently ongoing community transmission levels in all EU/EEA countries and the UK, if temperature screening is adopted by the national health or port authorities, it should include all points of entry and all passengers, using a specific protocol for primary and secondary screening, testing and follow-up. This entails huge human, laboratory, logistical (PPE, sample transport, passenger transit and quarantine, etc.) and monetary resources, which will be reduce the amount available for preparedness planning for a potential second wave of the COVID-19 pandemic.

Health screening questionnaire

A health questionnaire or health declaration form can be used as a tool for health monitoring before the cruise will start. The completed form should be assessed by a health professional for each passenger separately. This may entail re-checking the temperature and other vital signs and going over the questions in more detail to decide if the passenger should be referred for COVID-19 testing.

A questionnaire template is included below (Box 1), with a set of frequently reported clinical symptoms in COVID-19 cases.

However, it should be noted that no single symptom or combination of symptoms has proven to be pathognomonic for the disease. Cough and fever are by far the more frequent symptoms, while malaise, myalgia and anosmia (sudden loss of smell) or dysgeusia (loss or change of taste) are much less frequent and are usually associated with milder cases. Combinations of answers including cough and/or fever are more suggestive of COVID-19 in the context of widespread community transmission, while combinations without either of those two symptoms are less so.

Any combination, which includes sudden onset anosmia (loss of smell) should also be referred for testing.

As with other communicable disease contexts, possible or probable cases detected among travellers should trigger a thorough investigation including contact tracing. The data provided in the passenger locator form and the health questionnaire would greatly facilitate this task. Cruise operators and Member States should handle this information complying with the requirements under the General Data Protection Legislation (GDPR), taking into account the legal requirements under their national law.

Did you subscribe to our daily newsletter?

It’s Free! Click here to Subscribe!

Source: Europa