Eight people have tested positive for Andes virus following a hantavirus outbreak aboard the MV Hondius cruise ship, the World Health Organization confirmed on Wednesday.

The Andes virus is the only hantavirus strain known to transmit between humans, making this outbreak particularly concerning for health authorities.

The WHO said eight cases were laboratory-confirmed for Andes virus infection, two are probable, and one case remains inconclusive and is undergoing further testing.

Three people from the ship have died since it departed from Argentina on 1 April for a cruise across the Atlantic Ocean. Two of the victims had confirmed Andes virus infections, whilst the third is listed as a probable case.

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Hantavirus typically spreads from the urine, faeces and saliva of infected rodents. There are no vaccines or specific treatments for the rare disease.

All known cases in the current outbreak were people aboard the cruise ship.

The inconclusive case involves an American passenger who was repatriated to the United States. The passenger is currently asymptomatic and undergoing further testing after returning one positive and one negative result.

The WHO maintained its assessment of the public health risk from the outbreak at moderate for those who were on the ship and low for the rest of the world.

The origin of the outbreak remains unknown. However, the WHO believes the original infection occurred before the cruise began, as the first victim, a Dutch man (70), started showing symptoms on 6 April, whilst the virus’s incubation period is one to six weeks.

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