Ontario's health ministry is asking 7 more people to isolate due to a hantavirus outbreak. They are low-risk contacts.

These 7 people are in addition to 3 others who were asked to isolate after possibly being exposed to the virus while traveling. They are high-risk.

All 10 people must isolate for 45 days to be safe.

This brings the total number of people being monitored in Ontario to 10.

6 more people are isolating in Alberta and British Columbia. They have no symptoms. 1 person in Quebec is no longer isolating.

Someone is low-risk if they came into contact with a high-risk person.

In Ontario, high-risk people include a couple who were on a ship and a visitor to the Greater Toronto Area. They shared a flight with a cruise passenger who died of hantavirus.

The 3 high-risk contacts in Ontario are still healthy and have no symptoms.

The Public Health Agency of Canada says people who were on the ship or are high-risk contacts should not travel.

The World Health Organization director says the risk of hantavirus to global health is still low.

There are 11 positive cases of hantavirus internationally, including 3 deaths. No new deaths have been reported since May 2.

The World Health Organization director says there is no sign of a larger outbreak, but the situation could change.

Public health officials say Andes virus requires close and prolonged contact to spread and is not a pandemic threat.

It's not clear if testing people who may have been exposed to hantavirus but have no symptoms is useful.

Dr. Bonnie Henry says public health officials are discussing the issue as passengers from the ship return home.

Tests for some viruses aren't effective before patients develop symptoms.

There are two types of blood tests for hantaviruses.

If someone in Canada who may have been exposed to hantavirus develops symptoms, health officials are ready to test and treat them.

Alberta health officials say their two travelers are self-isolating at home.

If they show symptoms, testing will be done, but so far, there have been no symptoms.

A hantavirus scientist says health officials are in a unique situation because doctors wouldn't normally suspect the rare virus until a patient is showing signs of illness.

A negative test in someone without symptoms wouldn't necessarily mean they don't have hantavirus.

The incubation period can be several weeks, so a negative test in the first week doesn't mean someone is negative.

Four Canadians arrived on Vancouver Island and are self-isolating for at least 21 days.

Dr. Bonnie Henry says she has the power to require people to isolate, but it's a last resort.

Forced isolation is only used if people don't comply with the request to self-isolate.

A clinical professor says voluntary isolation is appropriate given the low chance of transmission.

Hantavirus can be transmitted, but not easily, especially when a patient is not symptomatic.

If symptoms develop, the individuals could be transferred to an isolation unit.

The province has established protocols and facilities in case symptoms develop.

A clinical professor says B.C. is striking the right balance in its approach.

There is a low risk of transmission from this virus, and officials don't want to overact.

The COVID-19 pandemic showed that people can be upset with restrictive measures.

Officials want to maintain co-operation from the population and demonstrate they are doing their best.

Stick to the facts.

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