By the time someone sneezy and pale walks into the room, your body’s immune system is already on high alert. A new study published in Nature Neuroscience reveals that our brains don’t wait for pathogens to appear in the body before activating their defenses. Your body begins to defend itself the moment your eyes and brain detect a sick person.If the images supplied by the researchers are any indication of the faces participants saw in VR, it doesn’t look so much like they’re sick as it looks like they have some jelly smeared on their faces. But if I saw someone with that much jelly smeared on their forehead, I would assume they were unwell, too.Your Immune System Turns it Up a Notch Around Sick PeopleIt’s as if your body has a built-in security system that flags suspicious biological behavior at a glance. Andrea Serino, the study’s lead author, explained that this early-warning response is where the immune system begins to gear up even before any actual infection has occurred. It’s the security guard watching a shoplifter through a store security camera before calling in support.The body doesn’t take any hint of illness for granted. It assumes that it’s better to overreact to a false alarm than to underreact to a real threat. This is also a pretty good explanation for why we have a natural aversion to anyone who looks like they were ripped straight out of a NyQuil commercial. That little hint of disgust you feel toward that person is a little bit of social conditioning, but it’s also your immune system taking cues from your brain and responding by raising the DEFCON level just a bit.Our bodies are vigilantly keeping an eye out for threats, and it has no issue with activating defensive shielding and warming up their turbo lasers if someone sneezes within earshot.The post Your Immune System Kicks Into High Gear at the Mere Sight of a Sick Person appeared first on VICE.