Why Is It Called A Cold?

A few days ago, I’m getting my son into bed. “Hang on,” I say, “you need to put these Lego blocks away.”

“Can’t we play?” he asks, hoping I won’t put him to bed just yet.

“No,” I say. Then I spot something by my foot and pick it up. “But I’ve got time to… give you a cold!” And I throw his plush rhinovirus at him.

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He laughs and shrieks and dives away, then grabs it and throws it back. We spend the next couple of minutes pelting each other with the cold, before I tell him it’s time to climb into bed. As he settles down, he asks “Why is it called a cold?”

Beats me.

What is “a cold”?

I mean, I know that the common cold is a rhinovirus, whatever that is. Or, at least, I think I know that. Honestly, that knowledge is predicated on the assumption that the people at Giant Microbes know what they’re talking about. Which – no offense to that company – is probably not the best primary source for information about disease and the organisms that cause it. Just for adorable plush representations for those organisms.

So, what is a cold? According to the Mayo Clinic,

The common cold is a viral infection of your nose and throat (upper respiratory tract). It’s usually harmless, although it might not feel that way. Many types of viruses can cause a common cold.

Let’s be honest here. You’ve probably had a cold at least once. You know what it’s like. But he’re the Mayo Clinic list of symptoms:

  • Runny or stuffy nose
  • Sore throat
  • Cough
  • Congestion
  • Slight body aches or a mild headache
  • Sneezing
  • Low-grade fever
  • Generally feeling unwell (malaise)

The discharge from your nose may become thicker and yellow or green in color as a common cold runs its course. This isn’t an indication of a bacterial infection.[/quote]

They also recommend that you see a doctor if you run a temperature greater than 101.3 degrees F (38.5 degrees C) or if you have a lower fever that lasts for five or more days, if you experience shortness of breath or wheezing, or if you have severe sore throat, headache, or sinus pain.

What causes a cold?

According to the CDC, there are more than 200 different viruses that can cause the common cold. Rhinoviruses are the most common, but it can also be brought on by respiratory syncytial virus, human parainfluenza viruses, and human metapneumovirus. Regardless of which organism causes your cold, antibiotics won’t work – antibiotics kill bacteria, not viruses. In fact, there’s currently no real cure for the common cold except time and suffering, and vaccinations are difficult as there are around 100 different rhinoviruses and each functions differently. So, you’d have to get around a hundred different vaccines to try and prevent the cold, and then you’d probably get it from one of the hundred or so non-rhinovirus causes anyway. So trying not to get sick in the first place is your best bet. Be sure to wash your hands, and try to avoid close contact with people who already have the cold. If you can.

Generally speaking, cold weather does not cause you to catch a cold.  Colds are caused by viruses, not by temperatures.  During cold weather, you’re more likely to be indoors which increases the odds that you’ll be around individuals who are carrying viruses that can make you sick.  However, there is some evidence that cold weather can be a contributing factor – rhinoviruses thrive in temperatures below the normal human body temperature, and it appears that cooler human cells generate fewer interferons – the proteins that help fight viruses and similar pathogens.  Still, you’ll have more luck not getting sick by washing your hands than by avoiding cold air.

What is a rhinovirus?

Adeno-Associated virus (AAV) capsid (3D data 2qa0 from http://www.rcsb.org). The single stranded DNA genome inside the capsid is not visible here. The virus is a small, replication-defective, nonenveloped virus. AAV infects humans and some other primates.AAV is not currently known to cause any disease and this lack of pathogenicity has attracted considerable interest from gene therapy researchers together with a other features: AAV can infect non-dividing cells and can stably integrate into human chromosome 19 at a specific site which makes this virus more predictable and a better choice than retroviruses for gene therapy since retroviruses present the threat of random insertion and mutagenesis, which can be followed by cancer. However, removal of the "rep" and "cap" portions of the AAV genome helped create AAV vectors for gene therapy that lack integrative capacity. Selected genes for gene therapy can be inserted in to the AAV vector between the inverted terminal repeats (ITR). AAV DNA is lost through cell division, since the episomal DNA is not replicated along with the host cell DNA. Clinical trials: AAV vectors have been used for treatment of cystic fibrosis and hemophilia B, Parkinson's disease, muscular dystrophy, Arthritis and Alzheimer's disease. The capsid contains 60 proteins. View is along the 2-fold icosahedral symmetry axis. Individual, small spheres are atoms making up the proteins. Hydrogen atoms are not shown.

The name “rhinovirus” derives from the Greek rhino- (meaning “nose”) and the Latin virus (meaning “poison, sap of plants, slimy liquid, a potent juice”). They are Group IV RNA viruses of order Picornavirales, family Picornaviridae and genus Enterovirus. The rhinovirus primarily infects humans through the mouth and nose, mostly because they thrive in a 33 degree C to 35 degree C (91.4 degrees F to 95 degrees F) environment – which is the temperature range found in the human nose, thanks to the constant passage of external air. Once in, they bind to receptors on the cells in your nose and throat, hijack the cellular mechanisms that replicate DNA and manufacture proteins, and churn out more copies.

Why is it called “a cold”?

That’s a really good question, and I couldn’t find any primary sources for an answer. Wikipedia states that the name “came into use in the 16th century, due to the similarity between its symptoms and those of exposure to cold weather”, and links to the Online Etymology Dictionary entry for “cold”. This states that the usage began in the “1530s, from symptoms resembling those of exposure to cold”. Which makes sense, I guess. I know my nose runs in cold air, regardless of whether I’m sick or not. And I usually feel cold when I have a cold.

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