It is an age-old scenario, etched into human history, reinforced by literary motifs: a ship carrying a deadly disease aboard is refused docking. Accordingly, media attention has been intense since early May, when it became known that a cruise ship lay off Africa’s coast and a potentially serious viral illness was spreading among the passengers.
In fact, the case, which is now being handled by the World Health Organization (WHO), has several peculiarities that catch virologists’ attention. The risk to the global population is considered low.
On 1 April, the “Hondius,” under the Dutch flag, departed Ushuaia. Ushuaia is the southernmost city of Argentina and the capital of the Argentine province of Tierra del Fuego. The “Hondius” is the world’s first Polar Class 6 cruise ship, built for expeditionary tourism. The current voyage was planned to take them to remote regions in the South Atlantic.
According to the WHO, on board were 147 people from 23 nations. Among the passengers was also a Dutch couple who had previously travelled through South America, and particularly Argentina. Only a few days after leaving Tierra del Fuego, the man developed fever, headache and mild diarrhea; his symptoms rapidly worsened, and he died on board on 11 April.
His body was transported on 24 April to Saint Helena, a British Overseas Territory, accompanied by the deceased’s wife, who had already shown early symptoms. On the same day, another passenger contacted the ship’s doctor; he was evacuated to South Africa on 27 April, where he remains in intensive care to this day.
Virus Originates in Rodents
After tests for several respiratory illnesses came back negative, infection with hantavirus was confirmed on 2 May. After the same day a further German passenger on board died, and the United Kingdom reported a cluster of severe respiratory illnesses and several deaths to the WHO.
In the meantime the Dutch wife who had disembarked at Saint Helena had also flown to South Africa. En route to Johannesburg, her condition rapidly deteriorated, and she died on 26 April in the emergency department. On 4 May the hantavirus diagnosis was confirmed in her case as well.
Hantavirus is a virus whose primary hosts are rodents such as mice and rats and which occurs in different variants in various regions of the world. The animals themselves do not become ill, but shed the virus. Humans can become infected, for example when cleaning up droppings or carcasses.
While European variants are rarely deadly, the viruses circulating in North and South America are significantly more dangerous. The Andes virus variant endemic to some regions of Argentina can cause hantavirus pulmonary syndrome—with mortality rates of up to 50 percent.
Case Demonstrates the Need for International Cooperation
Hantavirus pulmonary syndrome infections are reported regularly, but human-to-human transmission is rare in the vast majority of cases. Argentina saw a notable outbreak in 2018, when one infected person transmitted the virus to several others at a family gathering.
In the cruise-ship case, experts suspect that the Dutch couple may have been infected before the voyage began. Symptoms typically appear within one week to several weeks. The WHO emphasizes that “most routine tourist activities pose little or no risk of exposure to rodents or their excreta.” Human-to-human transmission has so far occurred only in very close contact situations.
The case underscores the necessity for international cooperation in cross-border virus outbreaks: Argentina’s health ministry says it is now intensifying domestic surveillance—no infection has ever been recorded on Tierra del Fuego, where the ship departed over a month ago. Precise diagnostics are being conducted by two virological centres in Africa. Passengers who may have had contact with the passenger who died in Johannesburg are being traced.
Ship May Dock at the Canary Islands
The Hondius has been anchored for days off the northwestern coast of Africa near Cape Verde. The island nation does not feel equipped to accommodate and monitor the passengers. In a WHO meeting held on Tuesday, it was decided that the ship should instead dock at the Canary Islands, a part of Spain.
There, there is a suitably equipped clinic. The Canarian government showed limited enthusiasm, but the Spanish health minister confirmed on Wednesday afternoon that the remaining symptom-free passengers aboard would be admitted.
One passenger who had already left the cruise in April and returned to Switzerland was tested there and is now confirmed to have hantavirus infection at the University Hospital of Zurich. Three more passengers were taken off the ship; two are seriously ill and are to be treated in the Netherlands. A German passenger who had close contact with the deceased on board is to be tested in Düsseldorf and may receive further treatment.
According to Martin Eiden, head of the reference laboratory for hantaviruses at the Friedrich-Loeffler-Institut, the outbreak represents an “extraordinary event from a scientific standpoint, particularly because a possible human-to-human transmission of the so-called Andes hantavirus is on the table.” It is a locally confined incident, with no signs of a new global threat.
Nevertheless, says Eiden, the incident demonstrates how important “international health surveillance, rapid diagnostics and transparent communication in unusual infection events” are. Contributed by María José Dugarte Bernal
