A hantavirus outbreak on a cruise ship is a concern for Canadians. Three Canadians are isolating after possible exposure.

Four Canadians are in quarantine on the ship. Officials will meet them on Friday.

Three people on the ship have died. The World Health Organization is investigating.

The outbreak raises questions about hantavirus and other public health threats.

Hantavirus spreads through contaminated rodent droppings and rarely from person to person.

Symptoms appear one to eight weeks after exposure.

There is no treatment for hantavirus, but early care can help.

Hantavirus does not spread like COVID-19, according to Dr. Maria Van Kerkhove.

Most hantaviruses spread from rodents to people, not between people. The Andes virus is an exception.

This virus spreads very differently from COVID or influenza.

A virus's reproduction number shows how contagious it is.

If the number is above one, the virus spreads quickly.

If it is below one, the virus stops spreading.

The reproduction number for the Andes hantavirus is not clear, but it is low.

Between 150,000 and 200,000 hantavirus cases occur worldwide each year.

About 200 hantavirus pulmonary syndrome cases happen each year, mostly in the Americas.

The COVID-19 pandemic had a reproduction rate of one to four.

One person with COVID-19 typically infected one to four others.

The COVID-19 fatality rate in Canada is around 1.1 per cent.

The hantavirus outbreak is not like the early COVID-19 pandemic.

Hantavirus is a different virus that has been known for a while.

This outbreak is not the start of a COVID pandemic.

Measles has a reproduction number of 12 to 18 in Canada.

Each person with measles infects 12 to 18 others on average.

The measles reproductive number can range from 1.5 to 770.

About three in 1,000 people who get measles will die.

RSV has a reproduction number of one to five.

An infected person typically infects one to five others with RSV.

RSV has a high fatality rate in full-term infants, especially those one to four months old.

The world is better prepared for the next pandemic in some ways.

However, progress is fragile, and more needs to be done.

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