Seeing a Sick Person Primes Your Immune System to Fight Disease

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Anyone who comes into work sick should go home. It’s irresponsible. In the time it takes to get to work, the infected person will have left a trail of their disease for any unsuspecting pedestrian to pick up. At work, touching doors, elevator buttons, and so on, there’s an even higher chance the disease will rub off on someone in the office. Fortunately, Esther Inglis-Arkell from io9 has good news. She writes that seeing a sick person will kick your immune system into overdrive.

Inglis-Arkell walks readers through an interesting second-person point-of-view of a person (you) subjected to tests getting your blood drawn; looking at photos of sneezing, sickly people; and then having your blood drawn again. She puts us in the shoes of the anonymous participants we often write about here on Big Think.

What you — the participant — may not know, though, is that in the time you were looking at a slideshow of sick people, your blood began producing cytokines. Inglis-Arkell describes them best as a group doctors often have trouble categorizing, explaining:

“They can be proteins or peptides. Some are generated by any cell with a nucleus, and some by specialized cells. And, although they’re all linked with the immune system, they all have different functions.”

So, a jack-of-all-trades.

In the case of seeing a photo of a sick person, however, people produce “bacterial-specific cytokines,” called interleukins. This signals a subset of white blood cells, called B-cells, to start hunting down bacteria. Meanwhile, yet another type of cytokine inspects the macrophages (responsible for consuming foreign bodies) for infection.

So, think of that the next time Mark from accounting shows up at work sick because he wants to display how dedicated he is to the company. Rest assured that even though Mark isn’t taking the proper precautions to stop the spread of the disease he’s coughing up around the office, you’re immune system is already on it.