An Australian passenger onboard a cruise ship at the centre of a hantavirus outbreak has opened up about the terrifying experience. 

Peter Marsh, 82, was travelling on the MV Hondius cruise ship in Tenerife, an island in Spain, when it was struck by the rodent-borne illness.

Three people died and four Australians, one permanent resident and one New Zealander were repatriated on May 15 and are completing a six-week quarantine period at the Bullsbrook Centre for National Resilience in Western Australia.

Mr Marsh told the ABC from inside the quarantine facility how he had decided to go on the cruise with a birding group from Sydney. 

He said nobody felt alarmed at first as people began to get sick.

'It was a very gradual process, and the gentleman who died first, it seemed like a once-only event,' he said.

'When we heard that the first deceased's wife had died, there was a huge shock, and everybody began to think, well, maybe this is something that's catching.'

Mr Marsh said the mood on the cruise ship visibly changed when everybody began to realise it was the hantavirus.

'It became clear that this was potentially a virus that could spread to all of us, and we were all acutely aware that it was able to kill people,' he said.

Mr Marsh took aim at one particular group of passengers, and accused them of conflating the outbreak and sparking panic. 

'Unfortunately, there were a few so-called influencers on board who at that time went into overdrive and published some absolutely appalling material,' he said.

'It showed, I think, gross irresponsibility on their part because it led families and friends all around the world … to believe that things were far worse than they were.' 

Mr Marsh did not blame anyone for the outbreak, saying it was 'nobody's responsibility'. 

'My feelings are that nobody's responsible for, or to blame for what's happened,' he said.

'The first person who died, obviously, was the person who brought the virus onto the ship, but he had no knowledge that was going to happen, and he had no symptoms when he got on the ship, and he paid the ultimate price.'

Mr Marsh said the cruise company 'worked assiduously' to 'minimise the risk' to the rest of the passengers. 

'We've also, I think, been very lucky that the Australian government has stepped up to bring us back to Australia under quarantine,' he said.

'While it's been somewhat tiresome being locked up for this six-week period, I think that if one person is saved from getting sick, let alone dying, as a result of our quarantining, then it's all well worthwhile.'

Mr Marsh revealed he and the other Australians in quarantine are allowed to walk around the grounds in two one-hour blocks each day. 

The group will be released next Tuesday and allowed to fly back to their homes in NSW and Queensland. 

Mr Marsh said he was excited to see his family.