Test Your Knowledge

In order to catch a cold or the flu (influenza), a person must come into contact with a cold or flu virus. This occurs through contact with an infected person – by inhaling virus particles (made airborne by coughing or sneezing) or touching contaminated surfaces and then touching one’s own mouth or nose.

Contrary to some popular notions, the following do not cause colds or the flu:

• Not wearing a jacket when it is cold or chilly
• Sitting or sleeping in drafty rooms
• Going outside with wet hair

Cold and the flu can affect anyone at any age, although children have a greater risk of contracting viral infections than adults. This may be due to the vulnerability of their developing immune systems, as well as the many environments in which viruses can be easily spread (e.g., school, playground, daycare facilities). Children average anywhere from six to 12 viral infections per year, according to the American Academy of Family Physicians (AAFP) – compared to two or three infections per year for adults.

Colds and the flu most often occur during the fall, winter and spring months. In North America, colds generally appear between August and May (with peaks from August to October and from April to May). Most flu infections appear between November and April (peaking in December through March).    

More than 200 viruses can cause colds. Rhinoviruses are the most common cause of colds and there are more than 100 different types of rhinoviruses. However, rhinoviruses do not usually cause serious illness. Other viruses responsible for the common cold include the coronavirus, respiratory syncytial virus, parainfluenza virus and adenovirus.