Yawns are contagious. For some people just reading about a yawn can set off a yawn in response. A lot of people (including my husband) get nauseous when they see someone else vomit. Scientists aren’t sure what causes these reactions, although many think it may have something to do with empathy. Still, there may be more going on than just compassion.

A recent study published in Nature Neuroscience found that merely looking at someone who shows signs of infection, such as coughing, a runny nose, or a feverish flush in the cheeks activates the hypothalamic-pituitary axis. Don’t worry. I’m not even going to try to explain what that is. They key point here is that the result of that activation is an immune response very similar to what you get from a flu vaccination. This response happens within two hours of seeing a sick face. The areas of the brain that detect threats also become active upon seeing a sick person.

The researchers were quite surprised by these results. They didn’t think the immune system kicked into gear until a pathogen was in the body. They’re hoping that with more research this information could be used to improve the efficacy of vaccines.

Meanwhile, the next time you encounter someone with a cold or flu, cover your face but don’t look away. The sight of infection might help keep you healthy.

Stay curious,

Avery

Image by Tyli Jura via Pixabay