General information on Seasonal Influenza

What is seasonal influenze?

Influenze (commonly known as the flu) is a contagious virus that circulates on a seasonal basis, usually from October to April, causing outbreaks of respiratory illness. People who get the flu may experience several symptoms including: fever, headache, chills, muscle aches, physical exhaustion, cough, sore throat and runny or stuffy nose.

Most healthy individuals are able to recover from the flu, but certain segments of the population, like the elderly and medically vulnerable (individuals more likely to become ill because of other complications), may experience further complications. In some cases the flu can be fatal.

What is an influenza pandemic?

An influenza pandemic (or 'pandemic') occurs when a strain of the flu virus changes in composition, becomes highly contagious, spreads easily from person to person and moves quickly around the world. Because the population is not immune to the new virus, it will affect more people and cause higher rates of illness.

There were three pandemics in the 20th century. The World Health Organization (WHO) declared the first influenza pandemic of the 21st century — the H1N1 flu virus pandemic — on June 11, 2009. It is not possible to stop the spread of a pandemic once it starts, but it may be possible to slow its spread and minimize the impact.

How is influenza different from an influenza pandemic?

 How does influenza (including pandemic influenza) spread?

All strains of influenza spread from person to person through coughing or sneezing. When you cough or sneeze, you spray tiny droplets that can move up to two metres (six feet) through the air and land on other people or surfaces. These droplets contain millions of germs and are the cause of infections such as colds and the 'flu'.

People become infected when they breathe in the germs, or when their hands come into contact with germs that are on surfaces (such as toys, utensils, handrails). The flu virus can live on different surfaces for up to 48 hours. If you touch something after someone has coughed on it and rub your eyes, nose, or mouth you can infect yourself.

For information on how to reduce your risk of infection, please see our Staying Healthy at Home, Work, School and in the Community webpage.

How long will a pandemic event last?

As it is impossible to know what an influenza pandemic event might look like, certain assumptions need to be made. Pandemics typically occur in waves. The first wave is expected to last six to eight weeks and the second wave may follow six to nine months later; the level of illness in the second wave may or may not be more severe than the first. There may also be a third wave. When a pandemic occurs, communities can expect to deal with its effects for up to 12 to 18 months.

What is being done to reduce the impact of a pandemic?

All levels of government are currently making plans to reduce the impact of a pandemic. Please see Waterloo Region's Pandemic Plan for more information.