According to the Public Health Agency of Canada (PHAC), the seasonal flu affects up to 25 percent of Canadians every year.
An estimated 4,000 to 8,000 Canadians die every year from flu-related illness. According to WHO, it causes three to five million cases of severe illness worldwide.
Influenza is a common respiratory illness. It’s “not just a cold, and it has the potential to cause serious illness and death,” writes author and emergency physician Dr. Vincent Lam in the timely book The Flu Pandemic and You (Doubleday Canada, 2006), co-authored by Lee.
There are various types of influenza: the ones that affect humans are strains of A, B and C (the mildest) and they have the potential to modify and mutate as they reproduce. (The annual flu shot offers protection again the three most common A and B strains of the season.) Because of their makeup and continually changing genetic character, only influenza A viruses have the potential to become pandemic.
The newest one on the list—Swine flu— is just one example.
There have been others throughout history: in 1580, the first recognized pandemic was recorded, although the strain was not known. The 20th century saw severe pandemics like the Spanish flu of 1918-9 and more moderate ones like the Asian (1957-8) and Hong Kong (1968-9) flus. Lee even documents a recent false pandemic in 1976 when 230 U.S. soldiers were infected with the H1N1 (also known then as the Swine flu and the American government pursued a campaign to vaccinate 45 million people.
“Pandemic influenza causes higher than average severity of illness and death, but it happens only every few decades. Seasonal influenza causes a more predictable range of illness and death, and it comes every year,” say Drs. Lam and Lee.
So, what to do if you have the flu?
“The level of risk depends on the time of year, destination and duration of travel,” states the Public Health Agency of Canada (PHAC). It says the flu season in this country typically runs from November to April. But for travellers it’s important to know when the flu season hits the country you are visiting. If you’re going to Australia, for example, influenza season occurs during its summer—the northern hemisphere’s winter. In all cases, and in particular in the Tropics where influenza is year-round, the best thing to do is to get your regular flu vaccination during the ‘flu season.’
But those making a trip several months following their vaccination should take heed.
A flu shot typically offers only about four to five months of good protection and the vaccine recommended for another hemisphere may be a little different, explains Lee. That’s why he suggests seeking health advice from a physician specialized in travel medicine, which is often not covered by provincial health insurance. “A lot of people don’t end up spending the fee, then they get no advice or wrong advice,” says Lee.
Seeking medical advice early can save a life. Lee cites a scenario for the adventurous traveller: If you’re venturing on a 10-day jungle trek and there’s no way to see a physician during that time, the travel medicine expert could advise you on the differences between tropical disease like malaria or dengue fever and influenza— which have similar symptoms—and arm you with appropriate medications for both.
If you are showing signs of influenza, you’ll likely experience symptoms over seven to 10 days, including headache, chills and cough, then fever, runny nose, watery eyes, throat irritation, loss of appetite and sometimes nausea, vomiting and diarrhea.
If you have the option to seek medical advice, use the same threshold to seek a physician’s advice abroad as you would when you’re sick at home, says Lee. Aches and fever can be treated with acetaminophen and other symptoms should subside after lots of fluid and rest. But if you’re not getting better or you’re, importantly, having trouble breathing, check to see if your hotel has an in-house doctor or make an appointment with a local physician. Alternatively, find the nearest hospital. You might be prescribed an antiviral medication, though it needs to be taken within the first 48 hours of feeling ill to be effective.
Lee says he hopes travellers will be following doctor’s orders in protecting against influenza in the coming months, when cases of influenza typically climb. “I do the same when I’m travelling,” he says. “I get my flu shot, carry hand sanitizer and avoid crowded conditions.