Because ships are at high risk of COVID-19 infection in port during crew changes, the EU & IMO recently issued urgent new guidelines requiring ships to implement pre-boarding screening of seafarers to help combat the escalating problem. The effect of an outbreak on a ship would be catastrophic in business and human terms. No-one wants a medevac, major diversion or let alone a preventable death to deal with, on top of everything else they’ve got on at the moment.
Compared to workplaces in most other industries, ships crew are subject to increased risks from COVID-19 due to being confined in small spaces for extended periods of time in close proximity to other people. Furthermore, given the overwhelming dominance of male seafarers, and the fact that studies1 in Italy and Spain have shown approximately twice as many men as women die from COVID-19 as men, the dangers are intensified.
As we learn more about this disease there’s an increasing knowledge bank that shows a high proportion of infected people who are highly contagious, show no symptoms:
- A study2 into the outbreak on cruise ship Diamond Princess estimated that 20.6% – 39.9% of cases were asymptomatic
- According to the CDC, ~25% of cases show no symptoms.
- A study3 of the infected Japanese evacuees from Wuhan showed that 41.6% were asymptomatic
- An article7 in the British Medical Journal reports that four-fifths of cases are asymptomatic!
According to McKinsey4, studies in China & Singapore report that asymptomatic transmission may account for ~50% of cases. As China begins to return to work and daily life, they still experience small outbreaks and new cases. It’s widely accepted that the asymptomatic carriers are those who contribute largely to the ongoing spread – often referred to as the “super spreaders”. This is why testing is being widely introduced as the best practice to adopt, to prevent spread. South Korea did so well at controlling the COVID-19 outbreak because they immediately began testing hundreds of thousands of asymptomatic people.
Therefore without extensive pre-boarding screening, it’s impossible to know whether new asymptomatic crew are bringing COVID-19 onboard and infecting the whole ships’ crew?
European Commission “Guidelines on protection of health, repatriation and travel arrangements for seafarers, passengers and other persons on board ships” 8th April 20205
So, it’s beyond doubt there’s a significant possibility that asymptomatic yet highly contagious new crew (who have the disease) could board and infect the whole of ships’ crew. This is a key reason behind the European Commission publishing new guidelines centred around protecting the health of seafarers and introducing new requirements for the pre-boarding screening of crew.
Key paragraphs of the text are extracted below:
- In line with the advice referred to in paragraph 3, the primary option to ensure that seafarers at risk of infection with COVID-19 can start their duties should be testing before embarking.
- For seafarers with suspected infections and mild symptoms, testing should be performed in the next port of call and all crew members should have access to adequate medical care. As part of this, the person or persons in question should be evacuated and receive adequate medical care. If one person on board is suspected to be infected with COVID-19, all crew members should observe a 14-day quarantine, either onboard or land. This should be waived if the test of the crew member with the suspected infection is negative or after the quarantined crew member tests negative for COVID-19.
These guidelines follow similar directives issued by the International Maritime Organisation contained within IMO Circular Letter No.4204/Add.4 “ICS Coronavirus (COVID-19) Guidance for ship operators for the protection of the health of seafarers” 5th March 20206
“All ships are advised to….implement pre-boarding screening’
The new guidelines make it mandatory for ships to provide a declaration of health of all crew members, before being allowed to enter port. Going forward, every vessel’s ship master will be required to relay this information in advance:
- Total number of persons on board (both crew and passengers
- Number of persons infected with COVID-19
- Number of persons suspected to be infected with COVID-19
Only ships who have the diagnostic tools to test onboard will be able to satisfy these requirements.
It’s therefore critical that vessel operators consider how to BOTH protect against infection getting on their ships AND contain any outbreak if/when it occurs. Clearly, crew change represents the highest risk of introducing an infected/contagious person on board.
The new crew about to board can be categorised as follows:
- Totally free from any infection and never previously infected
- Totally free from any infection and recovered from previous infection
- Infected, without symptoms and within the widely accepted median 5-day incubation period
- Infected, past the incubation period and with symptoms
- Infected, past the incubation period & without symptoms
- With symptoms but not infected with COVID 19 (common cold)
- Relapsed/reactivated cases – scientists are studying this concept as ‘relapsed’ patients increase
Category 1 – subjects are of no concern and a confirmatory test will give some peace of mind to such crew & colleagues.
Category 2 – subjects are worthy to identify using the tests, as it’s generally recognised that these people will have developed immunity. They could be allocated to assist/care for any crew members that become infected whilst onboard.
Category 3 – there’s currently no commercially viable occupational screening test to detect subjects carrying the virus within the 5-day incubation period. It’s therefore important for ships to anticipate the potential for category 3 subjects and define a screening strategy to mitigate any risks – see later. It’s highly recommended that ALL CREW ARE RE-TESTED 5 days after crew change to diagnose any who’ve progressed from category 3 to categories 4 or 5 see below. On-board antibody tests offer excellent utility value in this scenario.
Antibody tests detect the presence of immunoglobulins which are produced by white blood cells as an immune response to viruses. Immunoglobulin M (IgM) is the first antibody to be made by the body to fight a new infection. IgM rises within the first week of infection AFTER the incubation period and is detectable after 3-5 days. At this time the subject has the disease and is highly infectious. They may or may not be showing symptoms. The IgG immunoglobulin, which is more abundant appears later, signally that antibodies are present which are responsible for longer term immunity. But again, the subject may or may not show symptoms.
The below figure explains the important role antibody screening tests can play in preventing Covid-19 outbreaks on ships.
For Category 4 ‘Infected and symptomatic’ subjects, it’s unlikely (but possible) that crew will turn up for work with symptoms given the plethora of advice and guidance issued. A possible scenario is that they leave home without symptoms and develop them whilst travelling to the embarkation point. A test combined with health questionnaire and forehead thermometer will provide conclusive diagnosis and result in refusal to board and isolation.
For Category 5 is the most significant risk – those crew members who are infected (i.e. have the disease) and are highly contagious, but without symptoms. Such subjects left undiagnosed (i.e. without pre-screening) would board and spread the infection to fellow crew, whilst being totally oblivious. The test will diagnose this category of subject with 97% clinical specificity.
For Category 6 subjects who are symptomatic but not Covid-19 infected (e.g common cold) as in category 4, it’s unlikely (but possible) they’ll turn up for work with symptoms given the plethora of advice and guidance issued. A possible scenario is that they leave home without symptoms but develop them whilst travelling to the embarkation point. A test combined with health questionnaire and forehead thermometer will provide a diagnosis and leave the decision to board in the hands of a medical professional.
For category 7 subjects, on-going periodic testing on-board would be the only way diagnose their re-activation from category 2.
So it can be seen from the foregoing that a prime use case for antibody tests on ships is catching the category 5 subjects (infected but asymptomatic) who in the absence of testing, would board and infect other crew. The referenced studies show there’s a high proportion (huge range 20.6% – 80% across the studies) of asymptomatic cases with the McKinsey4 study suggesting that asymptomatic transmission may account for ~50% of cases.
The tests offer further value in re-testing crew after 5-7 days (or thereafter) to catch those in category 3 (infected, without symptoms and within the incubation period) who progress to category 4 or 5. Similarly those in category 1 (totally free from any infection and never previously infected) that get infected and progress to category 4 or 5.
The 3rd utility value of antibody tests for ships crew is knowing-boarding who’s recovered from COVID-19 and likely immune, to assist with any who subsequently test positive during voyage.
The 4th utility value is the ability to test crew during voyage who become ill with diseases sharing similar symptoms e.g cough, fever, who are NOT infected with COVID-19.
Research by McKinsey & Company (COVID-19: Briefing materials 3rd April 20204) concludes that “Antibody tests are currently the best method for detecting asymptomatic cases”
Prof Ashley Woodcock8, Associate Dean for Clinical Affairs and Professor of Respiratory Medicine, University of Manchester, and Clinical Director for Respiratory Medicine, University Hospital of South Manchester commented8:
“Currently the ‘stick’ test will be invaluable as POC diagnosis. If positive, then the patient can immediately be triaged. False positives are rare. There may be 5% false negatives (IgM may not have yet gone up), but this can be checked in patients with the syndrome by re-testing”
CoronaSafeTM Antibody Screening Tests From Martek
To assist you comply with these important new guidelines and help protect your vessels from an outbreak of Covid-19, Martek has launched the CoronaSafeTM finger prick antibody screening test. From just a single drop of blood, CoronaSafeTM will detect IgM antibodies within 5-7 days of infection and is particularly useful to detect infections amongst subjects who show no symptoms and would otherwise embark undetected.
CoronaSafeTM has been proven in extensive clinical trials of 570 patients during the recent outbreak to deliver >95% accurate diagnosis of Covid-19.
The test is approved and certified by the European Union as meeting the safety, quality & performance requirements of European Standard IVDD 98/79/EC the highest standard applicable for these devices. It’s also in widescale use by authorities/corporations in Japan, China, Germany, Poland, Indonesia and is formally certified/approved by CFDA, Philipines FDA Singapore Health Sciences Authority.
Major Corporations & health practitioners worldwide are rushing to adopt these tests to help control the spread of this deadly virus, with demand rising rapidly as the crisis deepens.
To learn more click here
- British Medical Journal blog
- Study into the outbreak on cruise ship Diamond Princess estimated that 20.6% – 39.9% of cases were asymptomatic
- Study of the infected Japanese evacuees from Wuhan
- McKinsey Covid-19 Briefing
- European Commission “Guidelines on protection of health, repatriation and travel arrangements for seafarers, passengers and other persons on board ships” 8th April 2020
- IMO Circular Letter No.4204/Add.4 “ICS Coronavirus (COVID-19) Guidance for ship operators for the protection of the health of seafarers” 5th March 2020
- British Medical Journal article
- Expert comment on testing
The tests are further certified to the following additional International Standards:
- ISO 14971 Standard for the application of risk management to medical devices.
- ISO 13485 Medical Devices QMS certified manufacturer.
- EN 13975 Sampling procedure requirements for acceptance testing of finished in vitro diagnostic medical device.
- ISO 18113-2 Requirements for information supplied by the manufacturer of in vitro diagnostic (IVD) reagents for professional use.
- ISO 18113-4 Requirements for information supplied by the manufacturer of in vitro diagnostic (IVD) reagents for self-testing.
- BS EN 13612:2002 Performance evaluation of in vitro diagnostic medical devices (IVD MDs) including IVD MDs for self-testing.
Author – Paul Luen, CEO