The short version
- On US ships, 84% of cases that reached a shore physician were medical, 14% injuries and 2% psychiatric, across 866 cases in 48 months[1].
- Serious emergencies look different. Among officers who faced one, trauma was 37.9%, cardiovascular disease 18.2% and severe gastrointestinal disease 15.9%[2].
- 28.6% of 465 nautical officers had handled at least one serious medical emergency at sea[2].
- Suspected cardiovascular disease is the most common reason for a recommended evacuation[7].
- Denmark’s service now evacuates about 5% of cases, down from more than 10% in 1995[5].
Most calls are illness. Most emergencies are not
Search for the most common medical emergencies at sea and you get a boating app’s first aid list, a travel insurer and a video. None of them gives a percentage. The published data does, and it says two different things depending on what you count.
Count every call to a shore physician and illness wins by a distance. A study of US ships found 84% of cases were medical, 14% injuries and 2% purely psychiatric[1]. Count only the events that, in a survey of 465 officers, forced a port call, a course change or an evacuation and trauma leads, at 37.9%[2].
| Category | All physician calls, US ships[1] | Serious emergencies[2] |
|---|---|---|
| Injury and trauma | 14% | 37.9% |
| Cardiovascular | Within medical, 84% overall | 18.2% |
| Gastrointestinal | Abdominal problems in the top five | 15.9% |
| Skin or lung infection | Respiratory infection and rashes in the top five | 9.8% |
| Neurological | Not separately reported | 9.1% |
| Psychiatric | 2% | Not separately reported |
The practical reading: stock and train for the everyday illness load, and plan for the injury or cardiac event that ends a voyage. Those are two different jobs.
What US ships call a doctor about
The one peer-reviewed dataset we found from US ships covers vessels that must have medical care available and consult a physician before prescription medication is given[1]. It covered 866 cases and 1,720 contacts over 48 consecutive months, and 88% of patients were men, with a mean age of 43.7[1].
Five categories made up 43% of medical cases: respiratory infections, abdominal problems, genitourinary complaints, rashes and dental problems[1]. Injuries and psychiatric cases needed more contacts per case than medical ones, and psychiatric cases needed the most medication, with 12% needing four drugs[1].
Who can prescribe aboard
On a US vessel the person giving care is rarely a physician, which is why the call to shore matters. The rules on who may give what, and when a physician must be involved, are in who can prescribe medication on a ship.
What radio medical services see, country by country
Telemedical Maritime Assistance Services, the national radio medical centres, publish the widest data. Their case mix differs with fleet, route and era, so compare direction, not decimals.
| Service and period | Volume | Leading problems and evacuation rate |
|---|---|---|
| Denmark, 1995 to 2024 | 49,999 seafarers[5] | Musculoskeletal 18.8%, skin 14.6%, abdominal 11.5%. Evacuation now about 5%[5] |
| Sweden, 1997 to 2007 | 1,095 seafarer contacts[3] | Accidents 20%. Evacuation fell from 18% to 14%[3] |
| Poland, 2012 to 2018 | 225 consultations[4] | Infectious disease 27%, injury 20%. Evacuation advised in over 20%[4] |
| Italy, CIRM, 1935 to 2015 | 81,016 patients[10] | Container ships 2016 to 2019: disease 25 and injury 6.31 per 1,000 seafarer-years[6] |
One pattern holds across them: illness outnumbers injury by about four to one in routine traffic[6]. The Italian container ship data puts the ratio at 25 against 6.31 per 1,000 seafarer-years, and non-officers had about twice the officers’ rate of gastrointestinal and musculoskeletal disorders[6].
Cardiac events drive the evacuations
A 2023 review of 16 sources found that illness outweighs trauma and psychiatric conditions as grounds for evacuation, and that suspected cardiovascular disease is the most common reason an evacuation is recommended[7]. That fits the mortality data, where illness also leads: 245 of 449 seafarer deaths reported to the ILO for 2024 were health-related[11].
The diagnosis also varies by rank. In CIRM data from 2010 to 2018, cardiovascular disease was the sixth most common reason for a medical request, with hypertensive disease most common among officers (46%) and ischaemic heart disease among non-officers (41%)[8].
| AED training study, 130 ship officers | Before training | After 7 hours of training |
|---|---|---|
| Effective shock delivered | 81.7%[9] | 100% of 130[9] |
| Time to start of analysis | 72.4 seconds[9] | 60.4 seconds[9] |
The same study notes that ferries and merchant ships rarely carry AEDs, unlike cruise ships, and that Germany was the first flag state to require them on seagoing merchant vessels, by September 2012[9].
Psychiatric cases are rare and expensive
Psychiatric cases were 2% of US ship calls, and they cost the most per case[1]. Only 50% were resolved in a single contact, against 58% of medical cases and 42% of injuries, and they needed the most medication[1].
For a vessel, the lesson is planning rather than volume. A crew member in acute distress far from port ties up the officer giving care and the shore physician for days, and the chest has to hold what a physician may direct. The mortality side of this is covered in what kills seafarers.
What this data cannot tell you
Radio medical data counts calls, not everything that happens aboard. A cut treated from the first aid kit never reaches a physician, so call data will understate minor trauma, by design. The US dataset is also from 2007, and the Swedish data stops at 2012[1][3].
Evacuation rates depend on the service as much as the patient. Denmark attributes its fall from over 10% to about 5% to centralising the service in an academic emergency department with structured training[5]. Read each figure as a signal of direction and plan for your own route and crew.
The people handling it aboard
On most merchant ships the caregiver is a nautical officer. Of 465 officers on a medical refresher course in Hamburg, 133, or 28.6%, had dealt with at least one serious emergency[2]. On an 18-question test of basic shipboard medicine they averaged 70.7%, scoring 59.4% on hypothermia and 61.0% on treatment questions[2].
That is the gap a shore physician fills. It is also why the plan has to exist before the event: who calls whom, what the chest holds, and at what point the vessel diverts. See when to medevac a seafarer and remote vessel medical planning.
Match the chest and the plan to the data
| Emergency | Share in the data | What to have ready |
|---|---|---|
| Trauma | 37.9% of serious emergencies[2] | Wound, splint and haemorrhage kit, first aid kits by class |
| Cardiac | 18.2% of serious emergencies[2] | AED, oxygen, a written diversion threshold |
| Abdominal | 15.9% of serious emergencies[2] | Chest scaled to days from care, by flag state |
| Infection | 27% of Polish TMAS calls[4] | Antibiotics per the WHO guide[12] |
| Severe pain | Pain relief among the most common drugs given[1] | Scheduled analgesics under a DEA registrant |
Discovery Health MD builds that preparation around the numbers above. The chest is our ship medical chest management service, scheduled drugs sit in controlled substances management, and the emergency plan in maritime medical consulting. If you want a physician to check your chest and plan against this data, request a review, or begin with the six program decisions.
Common questions
What is the most common medical emergency at sea?
It depends on what you count. Among all calls from US ships to a shore physician, 84% were medical illness and 14% injuries[1]. Among serious emergencies that forced a port call, diversion or evacuation, trauma led at 37.9%, followed by cardiovascular disease at 18.2%[2].
What medical conditions most often lead to evacuation from a ship?
Suspected cardiovascular disease is the most common reason an evacuation is recommended, and illness overall outweighs trauma and psychiatric conditions as grounds for evacuation[7].
How often are seafarers evacuated for medical reasons?
It varies by service. Denmark’s radio medical service evacuates about 5% of cases today, down from more than 10% in 1995[5]. Swedish data showed 18% in 1997 and 14% in 2007[3], and the Polish service advised evacuation in over 20% of its 225 cases[4].
Who gives medical care on a merchant ship?
Usually a nautical officer with medical training rather than a physician. In a Hamburg study, 28.6% of 465 officers had handled at least one serious emergency, and they averaged 70.7% on a basic medical knowledge test[2].
Should a merchant ship carry an AED?
Germany was the first flag state to require AEDs on seagoing merchant ships, by September 2012[9]. In a study of 130 officers, 81.7% delivered an effective shock without training and all did after 7 hours of training[9]. Given that cardiac disease drives evacuations[7], it is a strong candidate for any chest review.
Are injuries or illnesses more common at sea?
Illnesses. On container ships reporting to the Italian service, the disease rate was 25 per 1,000 seafarer-years against 6.31 for injuries[6]. On US ships, 84% of physician calls were for illness[1].
Where do the most common shipboard complaints come from?
On US ships, respiratory infections, abdominal problems, genitourinary complaints, rashes and dental issues made up 43% of medical cases[1]. Denmark’s 30-year data puts musculoskeletal problems first at 18.8%, then skin at 14.6% and abdominal at 11.5%[5].
