After a long second summer in Europe, temperatures are starting to drop. Although the weather itself doesn’t make you sick, cold temperatures and reduced exposure to sunlight can make you more vulnerable to viruses.

This autumn, central Europe has been experiencing an atypically long second summer. As Dr. Alexander Stauch demonstrated in his article from last week, “Autumn returns after record October”, temperatures have been well above average when compared to the past 30 years.

But as you can see, it won’t last. In this first week of November, temperatures are expected to drop an average of 7-10 degrees.

Can you get sick from cold weather?

It’s commonly assumed that cold temperatures take a toll on our health and the medical community has enough statistical evidence to back this up. For example, on this chart from the American Centers for Disease Control and Prevention, you can see that the number of people infected with influenza increases in cooler seasons and decreases in warmer times.

But is it really the weather that makes you sick?

Technically, no. Even though respiratory illnesses such as influenza follow a seasonal trend, the weather itself doesn’t carry any virus or disease. Rather, it’s our social and physiological responses to weather patterns that create favourable conditions for the transmission of certain illnesses.

Why do people get sick in winter?

Viruses spread more easily in winter months because of a combination of factors resulting from low temperatures and humidity levels and reduced exposure to sunlight.

According to Harvard Medical School, while cold weather allows viruses to thrive, it suppresses people’s immune system. Reduced exposure to sunlight also contributes to a weaker immune system as we absorb less vitamin D. Furthermore, people tend to stay more indoors breathing the same air and in closer association for longer periods of time, which contributes to the spread of viruses.

Covering the first half of November, the plots below show that, besides temperature, as the northern hemisphere starts to lean away from the sun and the skies get cloudier, daylight hours will also be dropping.

Stay healthy! Be ready to get warmer coats and an extra dose of vitamins!

If you wish to do your own analysis of the cold months ahead, you can explore our data using the Weather API. If you don’t have access yet, you can test it for free!