The World Health Organisation has confirmed five hantavirus infections linked to the cruise ship MV Hondius, while three additional suspected cases are still being investigated. WHO Director-General Tedros Adhanom Ghebreyesus announced the development during a media briefing on Thursday and stated that although three people linked to the outbreak have died, the overall public health risk currently remains low. However, he warned that more infections could still emerge because hantavirus can have an incubation period extending up to six weeks.
The outbreak first came to attention after the United Kingdom informed the World Health Organisation about a cluster of severe respiratory illness cases among passengers travelling aboard the Dutch-flagged expedition cruise vessel MV Hondius. According to WHO officials, a total of eight cases have so far been identified among passengers and individuals linked to the voyage. Out of these, five cases have now been laboratory-confirmed as hantavirus infections, while three others continue to remain under investigation.
The first known patient reportedly developed symptoms on April 6 while onboard the ship and later died on April 11. At that stage, hantavirus was not initially suspected because the symptoms resembled those associated with several other respiratory illnesses. Health officials stated that no diagnostic samples were collected from the patient at the time, which delayed confirmation of the virus during the early phase of the outbreak.
To manage the situation, the World Health Organisation has deployed an expert team to assess passengers and crew aboard the vessel. The medical team includes a WHO specialist working alongside Dutch doctors and an expert from the European Centre for Disease Prevention and Control. Officials said the team is carrying out health screenings, collecting medical data, and conducting detailed assessments to evaluate possible infection risks among all passengers and crew members connected to the ship.
According to WHO, none of the remaining passengers currently onboard are showing symptoms of illness. However, health authorities continue monitoring everyone associated with the voyage because the virus can take several weeks before symptoms appear after exposure. Officials are also tracing individuals who may have disembarked earlier during different stages of the journey.
The World Health Organisation has already alerted 12 countries whose citizens had travelled aboard the vessel and later left the ship earlier in the voyage. These countries include Canada, Denmark, Germany, the Netherlands, New Zealand, Saint Kitts and Nevis, Singapore, Sweden, Switzerland, Turkey, the United Kingdom and the United States. Health agencies in these nations have been advised to monitor passengers and conduct contact tracing where necessary.
Despite the deaths and confirmed infections, WHO stressed that the outbreak linked to MV Hondius does not currently pose a major global public health threat. Officials stated that existing containment measures are considered sufficient and there is no evidence at present suggesting widespread or uncontrolled transmission.
Health experts also emphasised that hantavirus spreads very differently compared to COVID-19. Tedros Adhanom Ghebreyesus specifically clarified that the outbreak should not be compared to the coronavirus pandemic. He stated that this is not SARS-CoV-2, does not spread in the same manner, and should not be viewed as a pandemic situation.
According to WHO experts, most strains of hantavirus do not spread easily between humans. Human-to-human transmission is considered rare and usually requires extremely close and prolonged physical contact. In most situations, hantavirus infections occur after exposure to environments contaminated with infected rodent urine, saliva or droppings, especially when contaminated particles become airborne and are inhaled.
Medical authorities continue to monitor the situation closely because of the virus’s long incubation period and the possibility that additional cases may emerge after passengers return to their home countries. Investigators are also attempting to determine the exact source of exposure linked to the outbreak aboard the cruise ship.
The incident has once again highlighted the challenges health authorities face in managing infectious disease outbreaks aboard international vessels, where passengers and crew from multiple countries remain in close contact for extended periods during long voyages.
