There is no question that we will have to deal with an epidemic at some point. In part one of this series we looked at the hows of what can start a pandemic, now it’s time to look at how it will spread to Canada.
The second half of Pandemic flight path: How infectious disease spreads through the global airline transportation network was a lecture by Dr. Kamran Khan, Research Scientist at the Centre for Research on Inner City Health St. Michael’s Hospital.
When SARS hit Toronto Dr. Khan wanted to see if it was time to devote his life to how global population mobility was the key to pandemics. After running the numbers back and forth he knew that this was the way pandemics will travel in the 21st century. He had found his calling.
The way an epidemic moves throughout the world has changed in the last 50 years. In the past it was fairly easy to contain certain diseases. That was before you could fly from one point on the earth to any other point within 24 hours. Air travel has changed the way diseases flow. As Dr. Khan puts it, “It’s the perfect storm for infectious disease.”
Most diseases take a little bit of time for symptoms to develop. As we jet from place to place some passenger could be carrying a deadly virus within and no visible clues showing. By the time that the person is gasping for breath several cities globally could be having sick people spreading the virus without a clue. Welcome to the 21st Century Pandemic. Modern man has created the perfect route of traffic for wide spread death.
Let’s start with SARS. The disease started in Guangdong Province, China in November 2002.
It didn’t seem like anything really important when a farmer died at hospital. China didn’t even call WHO in about it. Then others got sick. An American flying out of China got sick on a flight to Singapore and died in hospital in Hanoi. SARS was getting ready to show the world something about how diseases travel today.
A group flew into Toronto from Hong Kong. They didn’t look sick. But as we know looks can be deadly and deceiving. As they crossed the ocean and the border those passengers were carrying a ticking time bomb in them. SARS had entered Canadian ground. In the end there were 438 cases of SARS, 44 of those cases resulted in death.
It put Toronto on the map and not in the best light. North America had it’s first real glimpse of a pandemic and fear was among us.
What’s interesting to note in the case of SARS, all the clusters were in industrialized areas. There were no cases in Africa or South America. There’s a reason for this. Air traffic. When looking at the air traffic of SARS it’s interesting to note that of every imported case in Toronto not one came from a flight that had multiple stops. Almost all of the cases of imported SARS came from non-stop flights.
What’s also interesting to note is just yesterday a case of suspected SARS came down in the wires in a small town in Russia. We have changed, we now know to be on the look out of what’s going on in our back doors. Because of SARS we now have better plans in motion to stop pandemics in their paths but it took the lives of 44 to get to where we are now.
We like to travel. We also like to get to new places quickly. This is not going to change, we’re not going to go back to the days of horse and buggy. While air travel has helped humans be able to cross the globe quickly it has also compromised global public health security. We have to be ready in advance. That’s why the Bio-Diaspora Project was started. It’s goal is to understand aircraft and how they move in aspects to global health.
“The airline industry is like a heart. Within the arteries are people going places through the body.”- Dr. Khan
There are 35,000 international airports around the world. The locations are dense in some areas and farther apart in others like South America and Africa. Most of the world’s airports are in the Northern Hemisphere. There are few places in the world that a Canadian boarding at Pearson can’t get to quickly or non-stop. One of those places though is sub-terrain Africa. You can’t get there directly from Canada. That’s an important piece of the pandemic puzzle.
When we in Toronto consider air traffic and pandemic we have to group ourselves with the United States. The concerns are the same. Fifty percent of international travel that comes into Pearson came via the states. The United States accounts for 13% of international traffic world wide, Canada accounts for 3%. Those guys in Europe travel internationally a lot more than we do. And they come here, as do people from Asia. In Ontario we can get to Asia, Europe, a few cities in Australia and the United States on a non-stop airline.
Now we have to look at the flows of air travel. Those flows are much like arterial blood pressure tracing. Time and events shape the flow patterns, after 9/11 and SARS the flows into Pearson were lower. Since 2006 though the flow is back up. Certain time periods also have larger peaks, the 3rd quarter of every year has the highest spikes of air traffic.
What this tells researchers is timing when it comes to a pandemic means everything. If a pandemic hits in the Northern Hemisphere during the third quarter of the year we are in BIG TROUBLE. More people will be exposed and carry the disease farther around the world than at any other time of the year. Researchers can also tell us where these pandemics will hit, not the little villages but the major hubs of international travel. In Canada that means in order; Toronto, Vancouver, Calgary, Montreal, Ottawa and Halifax. If you live in the Yukon you are pretty much safe from an epidemic this century.
The Bio-Diaspora Project is tracking air traffic. The researchers know where people are coming and going to. They have access to tickets, not personal information just locations. They know in Canada that each city has international hot spots. In Toronto the only African hot spot is Johannesburg, South Africa. In Montreal there are more African hot spots, in Vancouver it’s East Asia. This tracing of where the hot spots are located is important, many new diseases come from these areas.
The project will soon be allowed to study the flight traffic in real time. They will be able to have true data on weather changes and other factors in travel times. They will be able to work on emergency responce in a way that has never happened before.
Now let’s get down to brass tacks.
“No single country can protect itself.”- Dr. Khan
WHO has started planning for an international outbreak. Their vision is: An integrated global alert and response system for epidemics and other public health emergencies based on strong national public health systems and capacity and an effective international system for coordinated response. WHO has a treaty on how to prepare for outbreaks. The question is whether or not the treaty will do the trick according to Dr. Khan.
Threats to Canada
First off the main threat to Canada is natural pathogens that already exist and are in place. They just haven’t taken hold yet. There are also threats when labs that house the worst of the worst viruses and bacterias are breached. The most difficult to predict though is the threat of an intentional international release of pathogen.
Now it’s time for the truths. At this point we are still in the putting out fires phase. We do have the tools to start doing more than that but they are in their infancy. Once the disease has taken off the best we can hope for is to have the measures in place to stop the front line, those who are the first to get ill.
There is no doubt that we in Toronto are vulnerable. Pearson International Airport has the 4th highest volume of traffic in North America, more than Atlanta or Washington D.C. We are the front lines in Canada.
To be prepared we have to stay alert. But here’s some good news, the chances of an outside threat coming into Toronto are limited to 13 countries. Okay the bad news is that those same thirteen countries were also the ones that dealt with the SARS epidemic. Viruses of the 21st century have a flight path. Hong Kong, Eastern Asia, Sydney, Europe, LAX, New York, Toronto, Vancouver… the more industrialized a city, the greater the risk.
Fear is not productive. We have to prepare not only in Toronto or North America but globally. We have to be alert to disease patterns and alert other nations what is going on. This is not the time to think in terms of borders, pathogens have no borders.
“Fear isn’t productive. What researchers are trying to do with research is. Stop looking at the limits of borders and start up streaming the international realm. It’s the way of the future. We must be proactive to look upstream when it comes to pandemics.”- Dr. Khan
That means the people of the world have to understand that it takes money to stop disease flows. The richest countries like Canada will have to use money for under developed nations to save itself. When tax payers complain that $10 million was sent to Africa to work on TB that money is not only helping those in Africa but also in the long run the people of Canada. As Dr. Gardam puts it, most of the TB cases in Canada came from across the border. If we don’t help in those nations then we are setting Canada up for a huge fall.
Dr. Kahn also pointed out that clean water and sanitation has to be worked as a global partnership.
“We have to reach the point to prepare in advance. I think as we spread more domestically and far less upstream we see larger problems. The international common good will move us up stream. I see us as Canadians moving in that direction.”
Science has to sell the government though and it’s a hard sale point. Researchers have to show the government that it’s important to the economy to be pro-active.
So are we ready for the next pandemic?
Dr. Gardam says he’s more confident now than ever before. Canada has learned from the SARS epidemic what has to be in place. We are heading in the right direction. We just have to hope that the rest of the globe is also heading there as fast as we are.
But we don’t know the real answer yet. We can’t. The next big pandemic has yet to hit.