Hantavirus questions and answers with Ontario’s chief medical officer of health

TORONTO — Two Ontario residents are isolating at home in their rural community after disembarking late last month from a cruise ship that is now the site of a deadly hantavirus outbreak. Ontario’s chief medical officer of health, Dr. Kieran Moore, said the couple has no symptoms and the risk in the province is very low.

Moore spoke with The Canadian Press about what is known about the virus, how public health officials are monitoring it, and how the COVID-19 pandemic is shaping this outbreak response. This interview has been condensed.

This may be the first time many people have heard of a hantavirus. What should members of the public know about it?

Hantavirus is rare and normally spreads from animals to humans, but this South American strain in particular can spread from human to human, Moore said.

“Argentina has experience, and has shared that experience with the global community on how they follow up on it, and they’ve shared the samples, the genomics of the virus, so we understand the virus makeup. The one different thing is, for this virus, we still don’t have a vaccine, nor do we have a treatment, but we have some experimental treatments that may be effective. … So I hope you’re hearing: known virus, known pathway of spread, very limited human to human spread, but it does occur, and mainly from exposure in the Southern Hemisphere.”

What do we know about the Ontario couple who were exposed to this virus on the affected cruise ship? How are they doing?

They have no symptoms, have never had symptoms since leaving the cruise ship, and are in daily contact with public health officials, Moore said.

“If between the daily contact, they develop symptoms, they have a number to call, and we will co-ordinate the care and the testing and the followup for these individuals, and we’ll keep all of our health system partners informed if they ever do need treatment. We will monitor them for the full 45 days — roughly 45 days is the longest potential incubation period for this virus — and ensure that there’s low risk of transmission. They’re doing very well in good spirits and in regular contact with local public health and thankfully, doing what’s necessary to protect the rest of the community. … (It’s 45 days) from the flight that they took, leaving (the remote South Atlantic island of) St. Helena going to Johannesburg, because there was a sick individual on that flight. So not only were they exposed on the ship, they were exposed on the flight. So we’re being as cautious as possible, so 45 days from April 25.”

Public health officials must have learned a lot of lessons during the COVID-19 pandemic. How are those being applied in this situation?

The need for strong communication and collaboration was a key lesson and is especially necessary in an outbreak that happens at sea involving passengers from more than 20 countries, Moore said.

“We want to ensure that we’re as consistent as other nations at protecting and preventing this type of spread. Luckily, this virus is a low-risk virus to spread to others, and the WHO has declared this a low-risk event for the globe, but there’s always lessons learned. This is so unique to happen on a ship in the middle of the Atlantic, having transmission probably in Argentina, and then brought on board, and so there will be lessons learned on how to identify it even earlier, identifying risk, and then having these global meetings where we are all consistent in our approach to limit the spread.”

Talk of isolation and contact tracing is bringing up memories of the pandemic for some people. Is that colouring how we are viewing this outbreak?

Moore said he wants to reassure people this is not COVID.

“I have tremendous empathy to the public. I hope it doesn’t trigger too many individuals, but I do want to assure Ontarians, we have a plan. We’ve become experts in this type of activity, on contact tracing, on monitoring, on testing and ensuring Ontarians get the right care at the right time. So we’re on it. We are not traumatized by this. This is our expertise.”

This report by The Canadian Press was first published May 8, 2026.

Allison Jones, The Canadian Press