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Swine Flu

In 2009 there were cases of swine flu, which had the constellation H1N1  that originated from Mexico where the mortality from it was in the 30% category.

The first cases likely occurred in mid March 2009, but were only confirmed in a laboratory in California as H1N1 in early April 2009 when a returning visitor from Mexico turned ill.

According to this Lancet article (thanks to for this link) this strain of swine flu is actually a hybrid of human/avian/pig influenza. This means there is no species barrier (the virus is adapted to humans, pigs and birds) and it can travel around the world easier. However, it seems much less deadly than the feared avian flu that never materialized. The good news is that because of preparations for the bird flu in the recent past countries around the world take this present swine flu seriously and use isolation methods that have proven to be effective in the past against SARS. The other good news is that the present swine flu strain H1N1 is sensitive to two antivirals, one of them Tamiflu. It is unlikely that there will be a vaccine available in the near future as it will take months to manufacture enough vaccine doses for millions or billions to be vaccinated.

Here are some swine flu related questions (thanks to for this link) answered by an expert.

What can I do to protect myself?

· Wash your hands frequently and thoroughly, using soap and warm water, or use hand sanitizer
· Avoid close contact with those who are ill
· Keep your hands and fingers away from your eyes, nose, and mouth
· If you’re ill, stay home
· Cover your nose and mouth with a tissue when you sneeze. Throw the tissue in the trash after you use it. When you cough, do so into your sleeve to avoid spreading the flu bug.
· If you experience severe flu-like symptoms, talk to a health professional.

Are all cases of human swine influenza severe?

No. The cases reported in Canada and the U.S. were milder than those reported in Mexico. To date, almost all of the individuals diagnosed with swine flu to date in Canada and the U.S. have recovered. The cases reported in Mexico have been more severe, involving mostly healthy young people who rapidly progressed from mild illness to severe respiratory distress, within an average of five days.

 Swine Flu

Swine Flu

I have travelled to Mexico, California, or Texas recently, and I’m feeling sick, what should I do?

If you become sick with severe flu-like symptoms, especially respiratory symptoms like a fever and cough or difficulty breathing, stay home from work, call your doctor, and tell your health professional that you’ve recently travelled to those areas. If Tamiflu (=oseltamivir) or Relenza (=zanamivir) is taken in the first two days of the flu it will stop the flu from escalating (see Interim Guidance by CDC , archived; thanks to for this link).

Here is a summary of flu symptoms as found in three common respiratory tract viral illnesses.

How to Distinguish Between COLD, SEASONAL FLU and H1N1 Flu Symptoms

Headache uncommon with a cold fairly common with seasonal flu very common (in 80% of the cases)
Sudden onset gradual onset over a few days flushed face, dizziness, loss of appetite, vomiting & nausea develop over a few days. Diarrhea common. Symptoms last 4-7 days. rapid onset , often within hours. High fever, diarrhea, aches and pains last 4-7 days.
Fever rare with a cold common with seasonal flu in 80% of H1N1 cases a fever (temperature of 101°F or more) is usually present
Chills uncommon with colds mild to moderate chills present about 60% will have chills
Sore throat common with a cold common with the seasonal flu NOT commonly present with H1N1
Sneezing common with a cold common with seasonal flu uncommon with H1N1
Stuffy nose common; resolves within 1 week common with the seasonal flu this is uncommon with H1N1
Coughing a productive cough is common a dry, hacking cough is common a dry cough (non-productive) is common
Chest discomfort mild to moderate moderate; if severe, it could turn into pneumonia (see physician right away) often severe chest discomfort with H1N1
Aches slight body aches and pains can occur moderate body aches common severe body aches and pains common
Tiredness mild with a cold moderate, patients complain of lack of energy moderate to severe tiredness is common


Here are some useful links:

· The Public Health Agency of Canada
· The World Health Organization
· Centers for disease control and prevention: seasonal flu
· Tips from the Government of Canada on how to fight the flu
· Travel notices and advisories



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Last modified: September 14, 2014

This outline is only a teaching aid to patients and should stimulate you to ask the right questions when seeing your doctor. However, the responsibility of treatment stays in the hands of your doctor and you.