A cruise ship hit by the hantavirus arrives in the Canary Islands, where the passengers, some of the crew, will be evacuated.

Dutch-flagged cruise ship hit by outbreak of deadly hantavirus reached Canary Islands in Spain early Sunday morning, where health officials will begin the complex process of evacuating the passengers and most of the crew, and returning them to their countries.

The MV Hondius, currently carrying nearly 150 people from more than 15 countries, including 17 Americans, sailed earlier this week from Cape Verde to the port of Granadilla in Tenerife – the largest of the Canary Islands – after Spain agreed to take over the ship.

Video from Reuters showed the ship near the port of Granadilla. Hondius was escorted by a Spanish Civil Guard ship, Agence France-Press reporters reported.

The World Health Organization said that, so far, none of those on board have shown symptoms.

There at least Nine confirmed or suspected cases of hantavirus have been linked to the outbreak, including the deaths of three people, a Dutch couple and a German woman.

Oceanwide Expeditions, which operates the ship, says all passengers and half of the nearly 60 crew members will begin evacuating the ship on Sunday using boats that hold five to 10 people. The release is coordinated by the WHO and several other health organizations. WHO Director-General Dr. Tedros Ghebreyesus went to Tenerife before the ship’s arrival.

After those people disembark, the skeleton team will pick up supplies and begin the journey to Rotterdam, the Netherlands, which is expected to take about five days, Oceanwide Expeditions said.

Once they are removed from Hondius, the Americans will be returned to the US by plane sent by the US Centers for Disease Control and Prevention and the Department of Health and Human Services.

The CDC said it is sending a team of epidemiologists and medical experts to the Canary Islands to “conduct an exposure risk assessment for each American passenger and provide recommendations on the level of precaution required.”

A medical evacuation flight will arrive at Offutt Air Force Base in Omaha, Nebraska, and the Americans will be taken to a special biocontainment unit at the University of Nebraska Medical Center.

Michael Wadman, medical director of the National Quarantine Unit at the University of Nebraska Medical Center, said each American will have their own room while in isolation for an unspecified period of time.

Hantaviruses are a family of viruses that are spread to humans from rodents through urine, feces or saliva, according to the CDC. It can take up to eight weeks after contact for symptoms to appear.

The WHO says the Andes strain, found in Latin America, is the only one known to be able to transmit the virus through human contact, with Ghebreyesus assessing the public risk as “low,” an assessment echoed by CDC acting director Dr. Jay Bhattacharya.

“Hantavirus is not spread by people who are asymptomatic, transmission requires close contact, and the risk to the American public is very low,” Bhattacharya said in a statement Wednesday.

The cause of this disease is still under investigation. However, before boarding the ship, the Dutch couple who died, a 70-year-old man and his 69-year-old wife, are believed to have spent weeks traveling through Argentina, Chile and Uruguay on a bird-watching trip in areas where there is a type of rat known to carry the Andes virus, Ghebreyesus said this week.

The man developed symptoms on April 6 and died on the ship on April 11, the WHO said, but no samples were taken because his symptoms were similar to other respiratory viruses, and hantavirus was not suspected at the time.

His wife then went ashore when the ship stopped at an island in the British territory of St. Helena. He showed severe symptoms on a flight to Johannesburg, South Africa, on April 25, and died in South Africa the next day, the WHO said. A test confirmed he had hantavirus.

A German woman showed symptoms on April 28 and died on the ship on May 2, according to the WHO.

Three other patients were evacuated by ship to the Netherlands for emergency treatment this week, while a Swiss man who started showing symptoms after disembarking was being treated in Zurich. A British man has been hospitalized in South Africa for treatment, while another British man who got off the ship has been hospitalized on the island of Tristan da Cunha, which is a British territory.

Oceanwide Expeditions said 32 passengers from about 12 countries disembarked from the Hondius in St. Helena, including a Dutch woman who died days later. Those American passengers who returned to the US before the disease was discovered supervision by state health agencies in California, Georgia, Texas, Virginia and Arizona.

The Hondius began a voyage on April 1 from Ushuaia, Argentina, that took it to several islands in the south Atlantic, including South Georgia and the South Sandwich Islands, Tristan da Cunha, Gough Island and St. Helena from April 21 to April 24.

The ship then stopped off the coast of Cape Verde, an archipelago off West Africa, a few days before heading to the Canary Islands.