Influenza is a respiratory infection caused by the influenza virus. In Canada, flu season usually runs from November to April and an estimated 10-25 per cent of Canadians may get the flu each year. Although most recover completely, an estimated 500-1500 Canadians, mostly seniors, die every year from pneumonia related to flu and many others may die from other serious complications of flu.
The influenza virus spreads through droplets that have been coughed or sneezed into the air by someone who has the flu. You can get the flu by breathing in these droplets through your nose or mouth, or by the droplets landing directly on your eyes. The flu virus is also found on the hands of people with the flu and on surfaces they have touched. You can become infected if you shake hands with infected persons or touch contaminated surfaces and transfer the virus to your own eyes, nose or mouth.
It is important to know the symptoms of illness related to influenza, and how to minimize your risk. Below are some answers to frequently asked questions and additional influenza links.
A case of influenza typically starts with a headache, chills and cough, which are rapidly followed by: fever; loss of appetite; muscle aches and fatigue; runny nose; watery eyes; and, throat irritation. Children may have nausea, vomiting and diarrhea, but these symptoms are uncommon in adults.
The most effective way to protect yourself from flu is to be vaccinated each year in the fall. Flu shots are especially important for: adults and children with chronic heart and lung disease; anyone living in a nursing home or chronic care facility; people 65 years of age older people with chronic conditions such as diabetes, anemia, cancer, immune suppression, HIV or kidney disease; children and adolescents on long-term acetylsalicylic acid (ASA) therapy; health care workers, other caregivers and household contacts capable of transmitting influenza to the above at-risk groups; people at high risk of influenza complications who are traveling to areas where the flu virus is likely to be circulating.
Certain groups should not be vaccinated. These include children under six months of age and people who have had a severe allergic reaction to eggs or a previous dose of vaccine.
Regular hand-washing is another way to help minimize your risk. By washing your hands often, you will reduce your chances of becoming infected after touching contaminated surfaces. If you get the flu, you should increase the amount of fluids you drink (water, juice, soups) and get plenty of rest for seven to ten days. There are also new medications to treat influenza. If you take them within 48 hours of the start of your symptoms, they may reduce the length of your illness by an average of one or two days.
Q. What are the side effects of the flu shot?
- A. The most common side effect of the flu shot is soreness at the site of injection, which may last a couple of days. You might also notice fever, fatigue and muscle aches within six to 12 hours after your shot, and these effects may last a day or two.Some people develop a condition called “oculo-respiratory syndrome” after a flu shot. The symptoms include red eyes and respiratory effects such as cough, wheezing, chest tightness, difficulty breathing, or sore throat. In most cases, the symptoms are mild and disappear within 48 hours.Another rare side effect of the flu shot is Guillain-Barré syndrome (GBS). This is an autoimmune disease that attacks the nervous system and results in weakness and abnormal sensations. But most patients recover fully. Your chance of developing GBS as a result of a flu shot is one in a million.
Q. How does the flu vaccine work?
- A. After you get the flue shot, your immune system produces antibodies against the strain of virus in the vaccine. The antibodies are effective for four to six months. When you are exposed to the influenza virus, the antibodies will help to prevent infection or reduce the severity of the illness.
Q. Are there other health effects related to the flu?
- A. Another possible side effect related to flu is Reye`s syndrome, which can develop in children and teenagers who are given salicylates (aspirin) when they have the flu or chickenpox. Reye`s syndrome affects the central nervous system and the liver, and can be fatal. Do not give aspirin to children or teenagers with the flu, unless it is specifically directed by the doctor.