What happened on the cruise ship now linked to three Hantavirus deaths?

A cruise ship sailing from Argentina has become the site of a deadly outbreak of Hantavirus.

According to the Canadian government, three Canadians are isolating at home after being exposed.

The virus is regularly carried by rodents, but more rarely, it can be spread between humans. Symptoms include fever, muscle pain, fatigue, headache, nausea and difficulty breathing.

Swiss officials have identified the strain spreading across the cruise ship as the Andes strain, which can transmit between humans. This type of virus can cause significant disease where the chance of dying can be as high as 40 per cent.

But Dr. Zain Chagla, an infectious disease specialist from McMaster University, says the chances for a large-scale outbreak are low.

“It’s not an efficient virus going from person to person outside of perhaps really close contact settings like this cruise ship may have created,” Chagla said.

From that cruise ship, which set sail April 1, there have been three deaths with a total of five confirmed cases. According to the World Health Organization, the first death happened April 11.

The body of a 70-year-old Dutch man stayed on the ship until being removed April 24 in St. Helena. The next day, the man’s wife became sicker during a flight to South Africa. She collapsed in the airport and died in hospital April 26.

Argentina’s government’s leading hypothesis is that the couple contracted the virus while bird-watching prior to boarding.

On May 2, a German woman died just four days after falling ill and showing signs of pneumonia.

By May 3, the ship reached Cape Verde waters when the WHO announced it was investigating the outbreak.

Today, Foreign Affairs Minister Anita Anand announced two Canadians are isolating in Ontario and another in Quebec.

While the risk of infection is low, Chagla warns there may be more cases before the outbreak is over.

“Because of the long incubation period, the situation may get a little bit worse before it gets better, as we kind of get a sense of how many people were infected along the way,” he said.

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