Usually influenza A or influenza B is responsible for an outbreak. However, about every ten to 30 years the influenza A virus can change suddenly and significantly. A virus that has been long absent may also reappear. An influenza pandemic (world-wide epidemic) happens when one of these new viruses spreads quickly from person to person.
Influenza spreads easily from person to person through sneezing or coughing. Infected droplets enter the body through mucous membranes in the eyes, nose, and mouth. Frequent hand washing is very important in preventing the spread of the virus.
Flu symptoms usually develop one to three days after infection. Those with influenza are most infectious the day before and three to five days after symptoms begin. Symptoms include sudden fever, chills, headache, aching muscles, dry cough, extreme exhaustion, and poor appetite. Most people recover without serious problems. However, certain groups of people are at risk of complications such as pneumonia.
The best form of protection is to get an influenza immunization, or ‘flu shot,’ every year. Immunization also reduces serious illness in those who do develop influenza. Once you have the shot, it will take about two weeks to develop protection. In those who are young and healthy, the vaccine is 70 to 90 per cent effective if there is a good match between virus and vaccine. Protection lasts for about six months. Immunization also protects the elderly and those with weak immune (defence) systems because it reduces the severity and potential complications of illness. However, it is less effective in preventing infection in these people.
The best time to get immunized is usually in October or November - just before flu season. People who can spread influenza to those at high risk and those at high risk should be immunized. This includes pregnant women, young children, elderly persons, and individuals with certain chronic health conditions such as diabetes, heart or lung disease.
Generally, there is no treatment for influenza so knowing how to care for yourself and your family is important. Healthy strategies for flu season can also serve as good habits during a pandemic. These include influenza immunization, proper hand washing, good respiratory etiquette when coughing or sneezing, taking caring of yourself and others, and planning ahead.
Keeping yourself physically and emotionally well strengthens your immune system and reduces illness. Most people recover from influenza without any problems. However, flu can cause serious illness in the very young, those with certain medical conditions and in the elderly. These people must receive prompt medical attention if they develop flu-like symptoms.
All around the world, public health officials and organizations are on high alert for an influenza pandemic. A pandemic is very different from a local influenza outbreak. More people would become sick, their symptoms would be more severe, and more people would die. Since a pandemic would involve a completely different strain of the influenza A virus, no one would have protection against it.
Some experts believe that if a pandemic influenza occurred somewhere in the world, it might take about three months to reach Canada. Canadians would feel the greatest effect within five to seven months. Together with the provinces and territories, Health Canada has developed a plan to ensure appropriate steps are taken to protect Canadians. Influenza vaccine and anti-viral medications would be made available as quickly as possible. The plan involves slowing the spread of disease, reducing serious illness or death, and avoiding interruptions to essential services. By being prepared, you can help your family and community in the case of a crisis.
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