Can cold give you a cold?
The common cold is a viral infection of the upper respiratory tract, caused by this guy,
the rhinovirus. The rhinovirus is transmitted in two ways,
with airborne droplets, mostly created when people cough and sneeze, and with contact
with contaminated surfaces. Therefore, for you to get a cold, there has to a virus to
infect you, cold itself cannot give you a cold.
However, cold temperatures do influence the transmission of the virus, which is why we
get more cases during colder parts of the year.
First of all, the outer shell of the virus, its envelope, is solid when it’s cold, and
liquid when it’s hot. When it is liquid, the virus has a lower chance of survival on
its trip from person to person. Secondly, when it’s cold, the air is drier,
which means that mucous membranes get drier too, becoming less efficient at catching the
virus on its way in. Finally, and most importantly, during the
cold winter months most people spend more time inside, in close contact with others,
increasing rates of infection. Which is why you’re much more likely to get a cold if
you’re a student, than if you are a Hermit. So, in fact, the best advice to give during
the winter is not to not get cold, but to avoid other people. If you were kept in a
cold sterile room, with no rhinovirus anywhere, there is no way to get a cold, you’d just
be cold, and very bored.