Strengthening the immune system: how do I stay healthy in winter?

That's right: If a virus hits us and our immune system overcomes the intruder by creating very specific defensive weapons against him, these so-called antibodies can immediately render the pathogen harmless on a second contact – we stay healthy. Most childhood diseases, such as measles or mumps, are therefore only given once and are then immune to them for a lifetime.

However, it is not always just a single virus that is responsible for a disease, but rather, as is the case with the common cold, a whole arsenal of over 200 different viruses. And our immune system is guaranteed not to know one of them, so our noses will run again. Other viruses, such as the causative agent of the real flu, change so quickly that our immune system no longer recognizes them in the next flu season.

And then there are viruses – such as the herpes pathogen – that stay in our body for a lifetime. If our immune system is weakened by stress, UV radiation or certain drugs, the virus becomes active – the annoying blisters on the mouth reappear. They'll go away at some point, but we can't really and definitely get rid of the herpes virus.