“The number of times we catch flu falls through adolescence and early adulthood and by the time we are 30 or so, we only get flu about about twice a decade.

For the rest of our adult life we continue to get flu just once every five years or so.”

Read more: http://www.dailymail.co.uk/health/article-2977848/Why-flu-probably-just-cold-Average-adult-catches-virus-just-five-YEARS.html