Passengers on cruise ship with deadly hantavirus will need to isolate for several weeks

Passengers on board a luxury cruise ship where three people have died from suspected hantavirus will need to isolate for close to two months, an infectious diseases expert says.

A Dutch couple and a German national have died, while a British national was evacuated from the ship and was in intensive care in South Africa, officials said. Three more suspected cases affected people who were still on board the MV Hondius, one of whom had a mild fever.

The UN health body said its working assumption was that the initial case of the couple, who joined the boat in Argentina, were infected off the ship, perhaps while doing some activities such as bird watching, and that human-to-human transmission may have happened on board.

The ship was now moored off West Africa and the 149 passengers were not allowed to go ashore.

Massey University professor David Hayman told Morning Report given the possibility of human to human transmission, passengers would likely need to be isolated for close to two months.

Hantaviruses were globally distributed, Hayman said.

There was no vaccine or cure and there were various different types of it spread by rodents.

The hantavirus on the cruise ship was probably from South America, Hayman said, and would cause classic viral symptoms like a fever and gastrointestinal illness, but with the South American type especially, it caused pulmonary and cardiovascular disease.

Normally people contracted hantavirus from contact with rodents or their excretion, Hayman said, and human to human transmission was very rare.

"It's going to make it quite difficult to manage as the World Health Orginisation (WHO) recommends people should isolate for 45 days because there is a long incubation period... I feel for the passengers on the ship for this long period not knowing what is going to happen."

On the ship, Hayman said it was likely the passengers were practising physical distancing and were remaining in their cabins.

"Because we don't have way or preventing hantavirus transmission in people, no vaccine, the only thing we can do are those physical distancing and hygiene protocols like we used in the early days of the Covid outbreak."

Hayman said all that could be done for treating hantavirus symptoms was trying generic antivirals and trying to maintain fluids and control fevers.

"Really there's little you can do apart from supportive therapy."

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