TORONTO -- As the list of countries dealing with COVID-19 grows, a Toronto infectious disease expert says the virus outbreak is already likely at pandemic level – but that’s not clear because some countries are hiding the extent of their outbreak.

“People are kind of dancing around the word pandemic,” said Dr. David Fisman, head of epidemiology at the University of Toronto’s Dalla Lana School of Public Health. “This is probably a pandemic a week ago.”

He said efforts to contain the outbreak in China have been quite successful but what is happening now is that the virus is probably most problematic in places that aren’t identifying the scope of the outbreak. Fisman cited Iran as particular cause for concern.

He said his school’s statistical modelling shows that while Iran is reporting 60 cases, it likely has 20,000 or even many more.

Canada has two confirmed COVID-19 cases that are linked to travel in Iran, but is No. 31 in terms of where Iranians travel.

“Where do they travel to from Iran? They travel to Syria, they travel to Iraq, they travel to Azerbaijan, they travel to Turkey. And those are all countries that are quiet, but it’s exceedingly unlikely that Canada would be importing multiple cases from Iran, when those countries have no cases.”

Afghanistan, Kuwait, Oman and Iraq have now reported COVID-19 cases, but Fisman says that’s because authorities are now looking for them based on the situation in Iran.

Canada has confirmed 12 cases of COVID-19, including a new case in Toronto in a woman who returned from Iran. All the cases are in Ontario and B.C. Cases of the virus are now confirmed in 41 countries.

According to the World Health Organization, a pandemic is a worldwide spread of a new disease, and generally means an epidemic has spread to two or more continents with sustained person-to-person transmission.

The WHO has final say on whether worldwide epidemics have reached pandemic proportions. But that is not a cut-and-dry issue. There is no checklist of number of infections or deaths or number of countries affected. SARS in 2003 was never declared a pandemic, though it spread to 26 countries because it was relatively quickly contained.

If the WHO concludes a pandemic is underway with COVID-19, as many health experts expect will happen, it won’t require an official declaration, a WHO spokesperson said Wednesday.

The highest declaration level in an infectious disease outbreak is a public health emergency of international concern. The WHO declared that on Jan. 30. A pandemic simply means a new stage of an epidemic, said Christian Lindmeier on CTV's Your Morning.

“Declaring it a pandemic would not change anything in the treatment of cases.”

At this point, the WHO doesn’t believe pandemic levels have been reached, Lindmeier said, but the organization is concerned about preparation in many countries and has been warning about that for weeks.

“The world is not ready for this, this is absolutely clear. But the world is alarmed right now more than it was last week, I would think,” Lindmeier said. “Hence, countries are now really putting their efforts in to get ready to meet these demands.”

He said calling the situation a pandemic doesn’t fully reflect that individual nations are in much different situations when it comes to COVID-19.

“That’s why to put a blanket over it all is not the most suitable. But at the same time, when these pandemic levels are reached, there is no reason why not to call it a pandemic.”

Declaring a pandemic doesn’t grant the WHO additional powers, but it indicates the health authority no longer believes the disease is containable within a specific region or regions. It also signals that countries should shift to focusing on coping with COVID-19, rather than containment measures, such as overly traveller screening and quarantines.

One of the big challenges with this virus is that symptoms can be very mild or even non-existent but a person can still transmit the virus to others who then can be affected more severely. Symptoms can resemble a cold or flu, ranging from fever, cough, runny nose, headache, and general fatigue to more severe, such as acute respiratory distress, pneumonia, sepsis and death.

The virus can incubate a short or long time, with symptoms taking two day or up to 2 weeks to appear after exposure. Most people with mild symptoms recover within six days.

Canada's chief public health officer Dr. Theresa Tam says existing pandemic plans focus on influenza but can be adapted for COVID-19. Tam says detection programs are focused on travellers returning from regions of high infection, along with their close contacts, but that will need to shift to broader surveillance should community transmission within Canada occur.

Pandemic response also requires greater diagnostic and laboratory capacity, stronger infection control procedures in hospitals and other frontline health facilities, and preparing for surge capacity among older age groups and those with underlying health issues.

It also means keeping sick people away from others, for instance through home isolation, quarantine, or perhaps through closure of mass gatherings, Tam told CTV News. Workplaces must be prepared for people to stay home, either because they are showing symptoms or because they must care for someone who is sick.

“It is better for us to prepare for a more serious scenario even if this virus doesn’t turn out to be as severe.”

There is a balance to be made between keeping alarm in check and ensuring the public is prepared for what could come, says Tam.

“No matter what happens, our key message to everyone living in Canada is that everyone can do their part to change the potential trajectory and the impact of this virus in Canada by individually keeping yourself healthy, practising the respiratory hygienic measures.”

Science is showing COVID-19 is spread in close contact through droplets unleashed by sneezing and coughing. Tam urges those who are sick to stay home and cover their cough, wash hands frequently and keep home surfaces clean with a solution of one part bleach to nine parts water.

But Fisman says the health authorities, particularly in Ontario, need to be more forthcoming with Canadians about the likelihood that domestic epidemics are underway or coming.

“This could be in any country now, so travel histories have somewhat ceased to be meaningful. So we need clear, frank, honest, practical guidance from public health authorities about what people can do to take control and get through the next number of months or possibly year or two as this thing is circulating.”

Outbreaks in Italy and South Korea are showing profound effects on the healthcare system and the economy and Canadians need to understand the road ahead, he said.

The SARS outbreak in 2003 has left its mark on pandemic preparedness in Canada, says Colin Furness, who researches epidemiology at the University of Toronto.

“Every health-care system really needs to walk through the horror of an epidemic in order to develop a good response to it. We did that with SARS and I think we’re actually very far ahead of a lot of other health systems.”

But COVID-19 is a much different virus than SARS. About two weeks ago, scientists started to see transmission from people who were showing no symptoms and felt just fine, Furness told CTV News Channel.

“Once the virus is able to do that, we can say the virus is very successful, we’re not going to be able to contain it.”

With SARS, only those who were sick could transmit the disease to someone else. That made containment much easier, says Furness.

So while COVID-19 is more easily spread than SARS, the good news is that it is much less deadly.

Dr. Neil Rau, a medical microbiologist at Halton Healthcare Services and CTV’s infectious diseases expert, believes the WHO has not yet talked of pandemic because there isn’t enough certainty about COVID-19’s fatality rate or just how widespread the disease is.

What isn’t in doubt is that COVID-19 case counts will continue to rise and that more deaths will be linked to it but that doesn’t mean the global picture is getting worse or out of control, says Rau.

Right now, the “genie is in the bottle,” but once the language of this disease does switch to pandemic, the approach will shift, says Rau. Testing becomes less important, hospitals and nursing homes close to visitors, and a priority is placed on protection measures for health-care workers.

“The question is how much disruption do you cause, because that has huge economic ramifications and huge inconveniences. Do you tell people not to go to hockey games or Raptors games to prevent community amplification? Sometimes the mass disruption of reacting to a disease is worse than the disease itself.”