GENEVA, SWITZERLAND / EuroWire / — The World Health Organization said current evidence suggests human to human transmission of the Andes hantavirus occurred aboard the cruise ship MV Hondius, marking a rare outbreak involving the only hantavirus known to spread between people. In its latest update, WHO said the working hypothesis is that the first case was infected before boarding and that subsequent transmission likely took place on the vessel during the voyage.
WHO said 11 cases linked to the ship had been reported as of 13 May, including three deaths. Eight of the cases were laboratory confirmed for Andes virus infection, two were classified as probable, and one remained inconclusive pending further testing. The latest additions since WHO’s previous update were two confirmed cases in France and Spain and one inconclusive case in the United States, all among passengers who had been on board the vessel.
The outbreak prompted a multinational response after passengers and crew disembarked in the Canary Islands. WHO said most passengers and crew were repatriated on specially arranged non commercial flights, while the ship departed on 11 May for the Netherlands with 25 crew members still on board and two Dutch health and care workers monitoring their condition. The European Centre for Disease Prevention and Control also said the vessel is due to arrive in the Netherlands on 17 or 18 May.
Transmission linked to close contact
WHO said Andes virus is endemic in parts of South America, particularly Argentina and Chile, and that infections are usually acquired through contact with infected rodents or contaminated materials. Human to human spread is uncommon, but WHO and the U.S. Centers for Disease Control and Prevention said Andes virus is the only hantavirus documented to pass between people. Both agencies said such transmission has typically involved close and prolonged contact with a symptomatic person.
WHO said its investigation, supported by preliminary sequencing analysis, found the virus samples from different cases were highly similar, reinforcing the assessment that the cluster was linked to a single spillover event or a very small number of closely related spillover events. The agency said the first infection is believed to have occurred on land before embarkation, with investigators working with authorities in Argentina and Chile to clarify the source and circumstances of exposure.
International response expands
WHO said the public health risk remains moderate for those who were on board the ship and low at the global level. The agency said contact tracing is continuing across countries that received passengers or managed onward travel, while experts from WHO and ECDC were deployed to support epidemiological work and public health measures before disembarkation in Spain. WHO also said recommendations may be updated as further laboratory and epidemiological evidence becomes available.
ECDC said the risk to the general population in the European Union and European Economic Area is very low and noted that the rodent reservoir for Andes virus is not present in Europe. WHO said low risk contacts do not need routine laboratory testing or quarantine for outbreak control, but should monitor themselves for symptoms and seek medical evaluation if symptoms appear. The agency said early detection, isolation of cases and close follow up of exposed people remain central to containing the outbreak.