GENEVA/MADRID/PRAIA - Hantavirus victims on the ship MV Hondius in the Atlantic Ocean may have been infected prior to joining the cruise, and human-to-human transmission on board cannot be ruled out, the World Health Organization (WHO) said on Tuesday.

The agency received reports of hantavirus outbreak on the MV Hondius on May 2. Seven individuals of the 147 passengers and crew have been reported ill and three have died. The situation remains fluid, WHO's chief of Epidemic and Pandemic Preparedness and Prevention Maria Van Kerkhove told reporters in Geneva.

"One patient is in intensive care in South Africa, although we understand that this patient is improving," she said, adding that two other patients, still on board the ship, are being prepared for medical evacuation to the Netherlands for treatment.

Van Kerkhove stressed that the situation is being closely monitored. As a precaution, passengers have been asked to remain in their cabins while disinfection and other public health measures are carried out.

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"The plan is, and our highest priority is, to medically evacuate these two individuals" to make sure that they receive the required care, and there are no other symptomatic patients on board, she said.

The ship is set to continue on to the Canary Islands, Spain, and the WHO is working with the Spanish authorities "to do a full epidemiologic investigation, full disinfection of the ship," she added.

Hantaviruses are carried by rodents and can cause severe disease in humans. Thousands of infections are estimated to occur each year. People usually get infected through contact with infected rodents or their urine, their droppings, or their saliva.

As to the suspected origins of the virus, Van Kerkhove said that the initial patients -- a husband and wife -- boarded the ship in Argentina.

"With the timing of the incubation period of hantavirus, which can be anywhere from one to six weeks, our assumption is that they were infected off the ship," she said.

"We do believe that there may be some human-to-human transmission that's happening among the really close contacts," such as the husband and wife and others who have shared cabins, she noted.

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According to the WHO, human-to-human transmission of infection hantavirus between people is uncommon, but limited spread has been reported among close contacts in previous outbreaks of the Andes virus, which is part of the hantavirus group.

There are no specific treatments for hantavirus other than supportive care. "Typically, people will develop respiratory symptoms, so respiratory support is really important," Van Kerkhove said.

Cape Verde to airlift three patients

Meanwhile, Cape Verde will airlift three patients in the coming hours from the cruise ship MV Hondius, which remains anchored off the Port of Praia, National Director of Health Angela Gomes said Tuesday.

Speaking at a press conference, Gomes said the three patients requiring urgent medical care are in stable condition, with no new cases reported among the remaining passengers and crew.

The evacuation will be carried out by specialized air ambulances, with one aircraft already in Cape Verde and another expected to assist. "The transfer will take place as soon as all safety conditions are in place," she said, without specifying a timetable.

Gomes stressed that the risk to Cape Verde remains low, as no passengers have disembarked and there has been no contact with the country's territory.

 Spain to receive cruise ship

Also on Tuesday, the Spanish Health Ministry said in a statement that Spain will receive the MV Hondius in the Canary Islands in accordance with international law and the spirit of humanitarianism.

According to the statement, the WHO, in coordination with the European Union, has requested the Spanish government to receive the vessel currently located near Cape Verde, where hantavirus infection cases were detected during its voyage.

The European Centre for Disease Prevention and Control (ECDC) is conducting a comprehensive assessment of the situation on board to determine which individuals require urgent evacuation in Cape Verde. The remaining passengers and crew will continue to the Canary Islands, with arrival expected within three to four days. The specific port of call has not yet been decided.

Upon arrival, passengers and crew will undergo medical examinations and be managed through specially arranged facilities and transport systems for handling and transfer. The process will be carried out in a way that avoids contact with the local population. These measures will be implemented in accordance with unified case and contact management protocols developed by the WHO and ECDC, ensuring necessary safety guarantees.

The Spanish government said further details will be announced once the WHO and ECDC finalize the operational plan, and updates will be provided as implementation progresses.

Dutch cruise operator Oceanwide Expeditions confirmed late Tuesday that two crew members of MV Hondius suspected of having hantavirus and another individual associated with the guest who passed away on Saturday will be evacuated to the Netherlands, though no specific timeline has been provided.