Hantavirus outbreak on cruise ship ‘very different’ from covid-19, expert says

Health personnel assisting patients onto a boat from the cruise ship MV Hondius, while stationary off the port of Praia, the capital of Cape Verde, on May 6, 2026. Picture:  AFP via Getty Images

A consultant in infectious diseases has said people need reassurance that the hantavirus outbreak on a cruise ship which departed from Argentina is not comparable to covid-19.

Two Irish nationals, including a woman from Cork, are among the passengers aboard the MV Hondius, which is currently en route to the Canary Islands following the deaths of several passengers linked to hantavirus.

Professor Christine Kelly, consultant in infectious diseases at the National Isolation Unit, told RTÉ: “It's a very different virus and worst case scenario if we did have a case in Ireland we're well prepared for it and the National Isolation Unit is in a good place to be able to deal with it.

"I think we'll need to see how people do and I also think we need to be following international guidance. We will be guided by Argentinian experts as well as experts within WHO and ECDC. Our colleagues across Europe have been working really hard on this together.” 

Prof Kelly said any response from the Department of Health and the National Health Protection Office would be based on recommendations from the WHO and the ECDC.

She pointed out that the outbreak of the Andes variant of hantavirus had been “quite inefficient” in human-to-human transmission.

“So you usually have maybe one or two transmission cycles passed from one person to the next and maybe one other person before that outbreak comes to an end. So you're looking at within outbreaks the usual kind of maximum might be around 10 to 20 people which is fairly in keeping with what we're seeing on the boat at the minute. You have to remember there's 149 people on that boat. We only have eight suspected or confirmed infections," she said.

Medics escort a patients, evacuated from the MV Hondius cruise ship with suspected hantavirus infection, to an ambulance after being flown to Schiphol airport, Amsterdam, Netherlands, Wednesday, May 6, 2026. (AP Photo/Peter Dejong)

Prof Kelly said she understood why people were concerned.

"I mean Covid 19 had a devastating impact in societies both in Ireland and all around the world. People are going to be hyper aware of that. Hantavirus is a very different virus to Covid 19," she said. 

“That's borne out with the guidance that WHO has given us in terms of the fact that it's low risk to the general population in terms of the outbreak.

“Some of those differences are we've seen that there only really have been infections on the cruise ship itself. Hantavirus is not a new virus and there have been human infections of Andes virus since the 1990s and so we do have information on it, we do know bits and pieces about it.

“Human to human transmission is quite rare, it only really happens with very close contact so there are differences from Covid and the incubation period is longer. What we do also know at the moment is that everybody on board the ship at the moment seems to be asymptomatic. It's really important to draw that difference because when people are worried about cases and infections that's very different from somebody who may be a contact or may not be a contact and isn't sick at the moment.”

Prof Kelly said robust plans were already in place for all scenarios, whether the two Irish nationals developed symptoms or remained symptom-free. She added that current ECDC guidance recommends quarantine measures for those involved.

“There are tests available for the virus and also PCRs (molecular tests) and serologies,” Prof Kelly added.

The comments come as officials and experts in Argentina work to determine whether the country is the source of the hantavirus outbreak linked to the Atlantic cruise ship, amid reports that some passengers have already returned to their home countries.