How Do “Cold” Viruses Spread?

Apr 2, 2020, 10:37 AM by Dr. Sally Robinson


Human kind has only known about these tiny little germs that cause disease since the 1900’s.  Bill Bryson’s book, The Body, has an interesting discussion about microbes including cold viruses.  The discovery of the first mysterious agent causing disease with tobacco plants was a Dutch botanist, M. Beijerinck, who named this agent “virus” after the Latin name for toxin.

At first we thought all viruses caused disease but we now know that of the hundreds of thousands of viruses reasonably supposed to exist, just 586 species infect mammals and of those only 263 affect humans.  Viruses are incredibly successful, have survived for hundreds of millions of years and infect all kinds of animals.  They are terribly small, much smaller than bacteria and too small to be seen under conventional microscopes.

The most regular of unwelcome viral encounters is the common cold.  The common cold is not a single illness, but rather a family of symptoms generated by a multiplicity of viruses, the most common is the rhinoviruses.  These alone come in a hundred varieties, as do the coronaviruses.

A research facility in Wiltshire, England was called the Common Cold Unit and was finally closed in 1989 after not finding a cure for the common cold. They did do some interesting experiments.  In one a volunteer had a device that leaked a thin fluid at his nostrils at the same rate as a runny nose.  The volunteer then socialized with other volunteer at a “cocktail” party.  Unknown to any of them the fake nasal drainage had a dye which was visible under ultraviolet light.  After mingling a while the ultraviolet light was turned on and the “snot” was everywhere, on their hands, head and upper body, doorknobs, sofa, bowl of nuts, etc.  Another study at the University of Arizona the researchers painted or infected a doorknob to an office building and found that it took four hours for the “virus” to spread through the entire building, infecting over half the employees and turning up on every shared device such as copier or coffee machines.  The most reliable way to transfer cold germs is physically by touch.   They found that the average adult touches his face 16 times per hour. This is what makes washing your hands critical to keep from spreading the virus.

There are several short videos of these types of experiments on Youtube.  You can type in “see how germs spread” for a start which illustrates some of the above experiments.  Stay safe and wash your hands.

by Sally Robinson, MD Clinical Professor

Keeping Kids Healthy
Published 3/26/2020

Also See:  UTMB Pediatrics - Pediatric Primary Care
  UTMB After Hours Urgent Care  

"2019 Novel Coronavirus", H.Codey Meissner, MD, updated 2/8/2020 (,, viewed Feb. 21,2020.

“Hand Washing: A Powerful Antidote to Illness” by American Academy of Pediatrics, updated 1/28/2020,, viewed Feb 24, 2020.

Bill Bryson's, The Body (2019)