Why Do You Get Sick After Exams?

  • By Anna Rothschild
  • Posted 01.07.16
  • NOVA

Does it seem like every year you get sick the minute you start your vacation? Gross Science host Anna Rothschild decided to investigate why that might be.

Running Time: 02:23


Why Do You Get Sick After Exams?

Posted: January 7, 2016

Why do you always get sick after final exams?

I’m Anna Rothschild, and this is Gross Science.

First of all, you may not have been sleeping well—or, let’s be real, sleeping at all if you’re the sort of person who crams before a big test. And I know, people always say that sleep is super important, but scientists have actually tested this... by giving people the common cold.

153 willing participants were given nose drops containing rhinovirus, which is one of the many culprits responsible for the common cold. Turns out, people who slept on average less than seven hours a night in the weeks leading up to the study were almost three times more likely to get sick. And people who slept worse were even more likely to get the cold.

Stress can also have a huge effect on our health. Back in the 80’s, scientists at Ohio State University sampled the blood of medical students one month before their final exams, and then again on the first day of the exam period. They found that the activity of the students’ natural killer cells, which are immune cells that play a big part in fighting viruses, were significantly lower on the day of the exam when the students were more stressed out.

A final idea is that lots of us end up traveling right after exams because sometimes they fall right before the holidays. Airplanes bring people from different places, harboring different pathogens, into close contact. And as you can see here, the airflow on an airplane does a truly excellent job of spreading sneeze particles around.

In all likelihood, that post-exam cold probably comes from a combination of these factors—plus others like poor diet, lack of exercise, and the time it takes a particular pathogen to start replicating. And sadly, this phenomenon doesn’t seem to end after graduation. The same thing seems to happen throughout your life after stressful situations. More research needs to be done in this area, so for everyone’s sake all you future scientists of the world, get to work—but don’t get too stressed about it.




Host, Writer, Editor
Anna Rothschild
Brooke Havlik and Marshall Johnson
Additional Help
Janet Sonenberg and Sam Christensen
I Love You This Much B
Music Provided by APM
Original Footage
©WGBH Educational Foundation 2015


How Sneeze Particles Travel Inside An Airplane by ANSYS
Courtesy ANSYS
(Via Wikimedia Commons)Video S1 from Rak G, Mace E, Banerjee P, Svitkina T, Orange J (2011). "Natural Killer Cell Lytic Granule Secretion Occurs through a Pervasive Actin Network at the Immune Synapse". PLOS Biology. DOI:10.1371/journal.pbio.1001151. PMID 21931536. PMC: 3172191.


(used with permission from author)
Squeak Pack/squeak_10
Produced by WGBH for PBS Digital Studios


Woman Sick In Bed
©WGBH Educational Foundation


Want more info?

Study on the effects of sleep on health:

Study on the effects of stress on medical students:

PopSci article on how sneezes travel through airplanes:

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