The World Health Organization has sought to reassure the public after a hantavirus outbreak aboard a cruise ship left three people dead and triggered international tracing efforts involving passengers from at least 28 countries.

The outbreak was detected on the Dutch-operated vessel MV Hondius, which departed Ushuaia in Argentina on 1 April and is expected to arrive in Spain’s Canary Islands on 10 May. WHO officials confirmed five cases of hantavirus among eight suspected infections.

Speaking at a briefing, WHO infectious disease epidemiologist Maria van Kerkhove said the situation was “not Covid” and did not pose the same pandemic risk because hantavirus spreads through “close, intimate contact”.

Health authorities are tracing passengers who disembarked on St Helena in late April, including British, Dutch, German, Singaporean and American nationals. Several passengers have since travelled internationally.

WHO Director-General Tedros Adhanom Ghebreyesus said the overall public health risk remained low, although additional cases could emerge because the virus has an incubation period of up to six weeks.

Hantavirus is usually spread through contact with infected rodents. However, WHO said limited person-to-person transmission had now been documented during the outbreak, prompting increased monitoring measures on board the ship.

Authorities in Argentina are also investigating possible rodent exposure sites visited during a bird-watching excursion linked to the first confirmed cases.

Oceanwide Expeditions said passengers remaining aboard the vessel had been advised to wear masks and follow health precautions while investigations continue.