Britain widens checks after cruise virus case

Britain has confirmed two hantavirus infections among its nationals and is investigating a third suspected case on Tristan da Cunha, widening the public health response to a deadly outbreak linked to the MV Hondius expedition cruise ship in the South Atlantic.

The suspected case involves a British national on the remote UK Overseas Territory, while two other British nationals have already tested positive after being connected to the same voyage. Health officials say none of the British citizens still onboard the Dutch-flagged vessel is showing symptoms, but all are being closely monitored as the ship prepares to dock in Tenerife.

The episode has triggered a multinational contact-tracing operation after three deaths and several confirmed or suspected infections among passengers and crew. The outbreak has drawn attention because the strain involved is linked to Andes virus, a type of hantavirus found in South America that can, in rare circumstances, spread from person to person through close and sustained contact. Public health agencies, however, continue to assess the risk to the wider public as very low.

The MV Hondius left Ushuaia, Argentina, on 1 April for an expedition route through remote South Atlantic locations including South Georgia, Tristan da Cunha, Saint Helena and Ascension Island. Illness among passengers emerged during April, with symptoms including fever, gastrointestinal problems and rapid progression to pneumonia and acute respiratory distress in severe cases. One passenger died onboard on 11 April, while another died after being removed from the vessel at Saint Helena and transferred onward to South Africa. A third death was reported on 2 May.

The vessel, operated by Oceanwide Expeditions, had 147 to 149 passengers and crew representing more than 20 nationalities during the affected voyage. Thirty people disembarked at Saint Helena on 24 April, before hantavirus was confirmed. Those individuals have since become a priority for contact tracing because some travelled onward to several countries before the outbreak was formally identified.

Seven British nationals disembarked at Saint Helena. Two have returned independently to the UK and are self-isolating at home without symptoms. Four remain on Saint Helena, while another has been traced outside the UK. British authorities are also preparing for the return of passengers and crew who remain on the ship, with a dedicated repatriation flight planned after docking in Tenerife.

Those returning to the UK will be asked to isolate for 45 days, reflecting the incubation period associated with hantavirus infection. Public health and infectious disease specialists are expected to accompany the repatriation arrangements, with infection-control measures in place during travel and follow-up testing after arrival.

The ship was held off Cape Verde before being allowed to proceed towards the Canary Islands. Spanish authorities have been coordinating arrival arrangements, while health agencies in Europe, North America and Asia have monitored passengers or contacts who left the vessel at earlier points. The United States, Canada, Singapore, France, Denmark, Switzerland, the Netherlands and Germany are among countries involved in tracing, isolation guidance or testing.

Hantaviruses are carried mainly by rodents and usually infect humans through exposure to contaminated urine, faeces or saliva, particularly when particles are inhaled. The disease is not normally associated with casual human contact. Andes virus is an exception among hantaviruses because limited person-to-person transmission has been documented, although such spread is uncommon and usually requires close contact.

The outbreak has therefore created a complex response: authorities are trying to avoid public alarm while applying strict precautions for those with possible exposure. Health officials have stressed that the situation is not comparable to a highly transmissible respiratory pandemic, but the severity of illness in some patients has justified intensive monitoring.

The likely source remains under investigation. Early indications point towards exposure before or during the initial stages of the voyage in Argentina, where hantavirus occurs in some regions. Possible contact with infected rodents during land-based activities, including pre-cruise or expedition-related travel, is being examined. No final determination has been announced.

The medical chronology has complicated the response. The first fatality was initially treated as a death from natural causes, with hantavirus not confirmed until later testing. By the time the outbreak was recognised, passengers had already disembarked at multiple points and travelled onward. That delay has forced health authorities to reconstruct passenger movements, flight contacts and close interactions after the fact.