Influenza and Cold

The correlation between low temperatures in winter and influenza can be easily understood by combining some news stories in The Netherlands. The winter of 2013 was unusually long and cold. We were almost halfway the month of April before the spell broke and some milder weather appeared. In The Netherlands the lowest temperatures of the last 27 years were recorded (In Nederland zijn de laagste temperaturen in 27 jaar gemeten). Even on the 7th of April of 2013 records were broken; never before was it so cold.

The other thing that was unusually long was the influenza epidemic of 2012/2013. The Dutch Rijksinstituut voor Volksgezondheid en Milieu reported: ‘During the last seventeen weeks we experienced a mild flu epidemic in The Netherlands; the longest epidemic of the last 20 years’ (‘Er is sinds zeventien weken een milde griepepidemie in Nederland; de langst durende epidemie in de afgelopen 20 jaar’).

[Foto: theexaminer.com]

This data suggests that there is a correlation between low temperatures in winter and the duration of the influenza epidemic. However, this does not prove that there is a direct cause and effect between the two parameters because the cold weather may also keep people indoors and that in turn causes low levels of vitamin D. These low levels may leave you more prone to infections. See here.