Influenza

Influenza (flu) is caused by infection with influenza viruses. It mainly affects the throat and lungs, but it can also cause problems with the heart and other parts of the body, especially in people with health problems. Influenza viruses are seasonal and cause outbreaks each winter in Canada. Every few decades, a new type of influenza virus will emerge, causing a severe and widespread epidemic (or pandemic).

Your health-care provider may diagnose an influenza-like-illness by examination and symptoms. The specific diagnosis of influenza can only be confirmed by testing a sample of the fluid from the back of your nose and throat. 

Symptoms usually occur one to three days after infection, and they may include sudden onset of: 

• fever
• headache
• muscle and joint pain
• sore throat
• cough
• runny or stuffy nose
• severe fatigue

Children and the elderly may also have vomiting or diarrhea. 

Most people recover within a week. Compared with many other infections (such as the common cold), influenza tends to cause more severe symptoms and complications. Complications can include pneumonia, heart failure or worsening of other illnesses.

The influenza virus is easily spread by coughing, sneezing, talking and by contact with contaminated hands and surfaces. Infected people are contagious about one day before symptoms start until three to five days after. 

Anyone can get influenza. The elderly, people with other illnesses (such as heart disease, lung disease or diabetes), pregnant women and small children are most likely to develop complications. 

Drink plenty of fluids and get plenty of rest. For pain or fever, you can take medicine by following the manufacturer’s instructions. Ask your health-care provider what medicine is best. 

If signs and symptoms worsen, seek medical attention. Antiviral drugs for influenza (oseltamivir and zanamivir) can reduce the severity and length of illness if taken within two days of the first symptoms. They are only available for eligible individuals by prescription.

The best way to prevent influenza is to get the vaccine at least two weeks before the beginning of influenza season. The influenza vaccine is recommended for everyone six months and older. Yearly vaccination is especially important for people who are at high risk of complications from influenza, their caregivers and their household contacts. 

Children six to 59 months can receive the vaccine at their local Public Health Office or from their health-care provider.  Adults can receive the vaccine from their health care provider or pharmacist.  

Other ways to help protect yourself include washing your hands often, especially before touching your eyes and nose, and avoiding close contact with people who have symptoms.  

If you develop symptoms of influenza: 

• stay at home until you are better
• cover your coughs and sneezes with the inside of your elbow or with a tissue
• wash your hands with soap and running water after coughing, sneezing or blowing your nose and before touching other people or objects
• when visiting the doctor, call ahead to see if the doctor can place you in a separate waiting area and ask for a mask if you are coughing and have to wait near other people

Public Health monitors influenza activity by tracking the number and trends of influenza infections in the community, lab testing, types of virus strains, outbreaks in different settings (such as nursing homes and schools) and hospitalizations and deaths associated with influenza. 

For additional information, contact your health-care provider, local Public Health office or Tele-Care 811.