An article by Medical News Today explores the reasons behind our body’s susceptibility to the common cold and influenza viruses in winter.

Common cold and flu viruses try to gain entry into our bodies through our noses. Luckily, our nasal lining has sophisticated defense mechanisms against these microbial intruders. But cold air cools the nasal passage and slows down mucus clearance. Viruses can now stick around for longer, trying to dig through the snot to break into our body.

Rhinoviruses actually prefer colder temperatures, making it difficult not to succumb to the common cold once the thermometer plummets. At a normal body temperature, these viruses are more likely to commit cell suicide, or apoptosis, or to encounter enzymes that make short work of them, a 2016 study showed.