Canada’s third likely case of coronavirus reported in B.C.

• The death toll has reached 132, with 6,078 cases in China. Here’s what we know so far about the disease.
• Japan and the U.S. have evacuated citizens from China. On Wednesday, the UAE reported a case, the first in the Middle East.

Three people in Canada have now tested positive for the new coronavirus, a development that is keeping health officials across the country on high alert as the global spread of the illness broadens.

Bonnie Henry, B.C.'s Provincial Health Officer, confirmed Tuesday the province has its first presumptive case of the new coronavirus, known as 2019-nCoV. The patient, a man in his 40s, recently travelled to Wuhan on a business trip, the centre of the outbreak in China. He began developing symptoms more than a day after his return and, following public health messaging, contacted a primary care provider on Sunday. He tested positive for the virus late Monday night, but those results have to be confirmed by the National Microbiology Laboratory in Winnipeg.

Canada’s two other cases, which have been confirmed by the national lab, are a husband and wife who returned to Toronto last week after travelling in the Wuhan area. The husband is recovering in isolation at Sunnybrook Health Sciences Centre and the wife, who has mild symptoms, is in self-isolation at home

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During Question Period on Tuesday, Prime Minister Justin Trudeau said the risk to Canadians is low and that government officials are working to ensure the virus is contained.

“We will continue to make sure that Canadians remain safe amid these concerns about public health,” Mr. Trudeau said.

The federal government is also providing consular assistance and looking at options to repatriate Canadians who are stuck in China due to travel restrictions imposed by the government.

Foreign Affairs Minister François-Philippe Champagne said Tuesday that 250 Canadians in Hubei province, where Wuhan is located, have registered with the Canadian government. He said 126 have requested consular assistance.

What will determine the spread

of the nCoV virus?

The likelihood that a virus will spread through a

population depends on several things including

population susceptibility, environmental factors,

public health measures and a number called R0.

What is R0?

R0 is short for basic reproduction number. It is the

average number of additional cases that could result

from a single case where no one is immune to the

disease. When R0 is greater than 1, the virus has the

potential to spread through the population if inter-

ventions are not put in place. Independent estimates

suggest the new virus has an R0 that is greater than

2 but the number can be highly variable.

R0 number of some common infectious diseases

Measles

Chickenpox

Polio

Mumps

12-18

10-12

5-7

4-7

SARS

nCoV

coronavirus

Influenza

(seasonal)

2-5

2-3.1*

0.9-2.1

*Jan. 26 Harvard Medical School estimate

From pandemic to endemic

GENERATION

A hypotheti-

cal new virus

with R0=3

would be

expected to

move quickly

through a

vulnerable

population.

1

2

3

Case of

disease

Immune

individual

Initial phase of epidemic

(R0=3)

GENERATION

Viruses that

have been in

the human

population for a

long time

typically have a

lower R0. They

may persist

because of

reinfection or

be sustained by

the gradual

turnover of the

population.

1

2

3

Disease is endemic

(R0=1)

Endemic= Disease is permanent

Epidemic= Disease outbreak is widespread

Pandemic= Worldwide epidemic

IVAN SEMENIUK AND JOHN SOPINSKI/THE GLOBE

AND MAIL, SOURCE: NIH; WHO; CDC; CMAJ; hse;

science direct

What will determine the spread

of the nCoV virus?

The likelihood that a virus will spread through a popula-

tion depends on several things including population

susceptibility, environmental factors, public health

measures and a number called R0.

What is R0?

R0 is short for basic reproduction number. It is the aver-

age number of additional cases that could result from a

single case where no one is immune to the disease.

When R0 is greater than 1, the virus has the potential to

spread through the population if interventions are not

put in place. Independent estimates suggest the new

virus has an R0 that is greater than 2 but the number can

be highly variable.

R0 number of some common infectious diseases

Measles

Chickenpox

Polio

Mumps

12-18

10-12

5-7

4-7

SARS

nCoV

coronavirus

Influenza

(seasonal)

2-5

2-3.1*

0.9-2.1

*Jan. 26 Harvard Medical School estimate

From pandemic to endemic

GENERATION

A hypothetical

new virus with

R0=3 would

be expected to

move quickly

through a

vulnerable

population.

1

2

3

Case of

disease

Immune

individual

Initial phase of epidemic

(R0=3)

GENERATION

Viruses that have

been in the

human popula

tion for a long

time typically

have a lower R0.

They may persist

because of rein-

fection or be

sustained by the

gradual turnover

of the population.

1

2

3

Disease is endemic

(R0=1)

Endemic= Disease is permanent

Epidemic= Disease outbreak is widespread

Pandemic= Worldwide epidemic

IVAN SEMENIUK AND JOHN SOPINSKI/THE GLOBE AND MAIL

SOURCE: NIH; WHO; CDC; CMAJ; hse; science direct

What will determine the spread of the nCoV virus?

The likelihood that a virus will spread through a population depends on several things

including population susceptibility, environmental factors, public health measures and

a number called R0.

What is R0?

R0 is short for basic reproduction number. It is the average number of additional cases that

could result from a single case where no one is immune to the disease. When R0 is greater

than 1, the virus has the potential to spread through the population if interventions are not

put in place. Independent estimates suggest the new virus has an R0 that is greater than 2

but the number can be highly variable.

R0 number of some common infectious diseases

Measles

Chickenpox

Polio

Mumps

SARS

nCoV

coronavirus

Influenza

(seasonal)

12-18

10-12

5-7

4-7

2-5

2-3.1*

0.9-2.1

*Jan. 26 Harvard Medical School estimate

From pandemic to endemic

GENERATION

GENERATION

A hypotheti-

cal new virus

with R0=3

would be

expected to

move quickly

through a

vulnerable

population.

Viruses that

have been in the

human popula-

tion for a long

time typically

have a lower R0.

They may per

sist because of

reinfection or be

sustained by the

gradual turnover

of the popula-

tion.

1

2

3

1

2

3

Case of

disease

Immune

individual

Disease is endemic

(R0=1)

Initial phase of epidemic

(R0=3)

Endemic= Disease is permanent

Epidemic= Disease outbreak is widespread

Pandemic= Worldwide epidemic

IVAN SEMENIUK AND JOHN SOPINSKI/THE GLOBE AND MAIL

SOURCE: NIH; WHO; CDC; CMAJ; hse; science direct

“We are looking at all options to assist them,” Mr. Champagne said. “That’s our priority.”

Global Affairs Canada this week issued a new travel advisory for China, warning all Canadians to avoid travel to Hubei.

The virus, which was first disclosed by Chinese health officials to the World Health Organization (WHO) on Dec. 31, has been rapidly spreading. The vast majority of cases are in China. The virus has killed 132 people and infected many more as of Tuesday, with 5,989 confirmed cases in China and a further 9,239 suspected cases.

Canadian health officials say they expect to see an increase in cases here and are advising anyone returning from the affected area to monitor themselves for symptoms and report any to a health provider.

In Toronto, public health officials said they have contacted the vast majority of passengers who may have been exposed to the new coronavirus on a flight from Guangzhou to Toronto last week. None of the passengers are showing any symptoms, said Eileen de Villa, Toronto’s medical officer of health. The city has also set up a hotline for any other passengers on the flight who have questions or concerns.

In the case of the B.C. patient, Dr. Henry said local health officials are in contact with the man’s family and that the risk of the virus spreading in the province remains low.

Because the man did not develop symptoms until after he returned home, he posed no risk to those on his flight, Dr. Henry said. He is now in self-isolation at home and is doing well, with regular monitoring from Vancouver Coastal Health.

There are many unknowns about the new virus, such as how easily it spreads and how deadly it is. The WHO said Tuesday that about 20 per cent of people who become infected with the virus appear to develop severe illness, which includes pneumonia and respiratory failure, and in a subset of cases results in death. Those numbers could change as more cases are identified and studied.

But many infectious-disease specialists have emphasized that there is no evidence to suggest 2019-nCoV is spread by asymptomatic patients. The idea that people without symptoms could pass the illness onto others spread over the weekend after a Chinese health official made the claim.

Last week, The Lancet published a case study of a Chinese family infected by the new coronavirus. The study noted that one child in the family did not develop the illness and another did get infected, but didn’t display symptoms. Isaac Bogoch, an infectious-diseases specialist at Toronto General Hospital, said there was no indication in the study that the asymptomatic patient spread the illness.

Dr. Henry also refuted the claims during a news conference Tuesday, saying there is no evidence to support the idea. She said in cases that health officials have been able to study so far, “there’s no evidence of asymptomatic [transmission].”

The World Health Organization said it would study the issue to try and get a definitive answer.