COLDS: Everything you want to know about this illness from prevention to cure
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In January of
2004, my wife and I caught colds and suffered for two weeks.
Somewhere during this misery something snapped inside me and
screamed, "Enough! What are these things and what can I do to
prevent them?"
That launched me into an Internet search for everything I could find out about colds, how to prevent them and how to get rid of them. The information I gathered was informative but not comforting. Here's what I found:
First, a disclaimer: I am not a doctor or in anyway connected with the medical profession. Nothing I say should be taken as advice. All I'm doing is repeating information obtained from the following sources:
http://www.pmhs.org/crs/aha/crs/comcold.htm
http://www.intelihealth.com
http://www.lungusa.org/diseases/c&fo3/cold.html
http://www.commoncold.co.uk
http://www.commoncold.org
http://www.niaid.nih.gov/factsheets/cold.htm
I also got a lot of information from the Encarta 99 encyclopedia
What is the common cold?
The common cold is caused by one of several hundred types of viruses that attack the cells that produce the mucus membranes in the back of the throat. Only humans and the higher primates are susceptible to them.
What
is a virus?
A virus is simply a bag of raw DNA. It can't eat, move, or reproduce on its own. All it can do is attach itself to a healthy cell it happens to come in contact with. If this cell is one that the virus has evolved to attack, then it pumps its DNA into the cell. The cell's DNA is scrambled and reassembled into hundreds of copies of the virus. Then the cell dies releasing the new viruses to invade more cells. In the case of the common cold this process takes 10 hours.
What
do cold viruses look like?
Like this:
This is a scanning electron microscope image of rhinovirus number 14. Each cold virus has a slightly different shape and how it appears in a photo depends on how its image was taken and processed, but this gives the general idea. They are extremely small, on the order of a few tens of nanometers. You'd have to line up over 2,000,000 of them to make a line one inch long. A layer one-cell deep layer of them covering a single small postage stamp would be enough to infect the entire population of the world.
Why
is a
cold called a cold?
In ancient times, most people caught colds in winter when it was cold, hence the name. They thought colds were caused by the cold weather. Numerous scientific studies have proven that being cold does not cause people to catch colds or make them more susceptible. The reason people caught more colds in winter was simply because they collected together for warmth and their close proximity increased the spread of the cold from one person to the next.
How
do I catch a cold?
The cold virus is usually passed from person to person in mucus droplets coughed or sneezed out by an infected person and inhaled by an uninfected person. These droplets, especially those generated from a sneeze, can be extremely small and float in the air for many minutes. If you are outside in a high wind, someone with a cold several hundred feet from you may sneeze and the virus could be carried to you. You may never even see the person who infected you.
Another way to get infected is to pick up cold viruses on your hands by touching a surface, such as a door knob, that has been contaminated. Then if your hand comes in contact with your nose or your eyes the virus can be carried to the back of your throat where it can take hold. Cold viruses can survive several hours on a surface, depending on the environment. Cool dry conditions tend to reduce their lifetimes. Warm humid conditions enable the virus to linger much longer. If someone sneezes into a handkerchief and puts it in their pocket, the viruses on the handkerchief may survive all day. Virus particles in mucus in sealed test tubes will remain infectious indefinitely.
It is difficult to catch a cold by eating something infected with cold virus. The secretions of the mouth tend to kill the virus and any that survive end up in the stomach where gastric juices quickly destroy them. The lining of the esophagus is not susceptible to cold viruses.
Once you've come in contact with a virus, it can be carried to the back of the throat (specifically the adenoid area) where the cells it has evolved to attack reside.
Here they invade healthy cells and multiply with a vengeance. It can take a little as one single cold virus to give you a cold.
How
long after exposure
will
symptoms show
up?
It's possible that symptoms could appear in as little as ten hours after being exposed, but it usually takes two days. The length of the time it takes for enough cold viruses to develop to cause symptoms depends on whether it was a massive exposure (millions of cold viruses inhaled directly into the sinus cavity) or minor (one virus particle lodged in a nostril.) Also, each type of cold virus affects each person in a slightly different way. Some viruses are more aggressive and have more pronounced symptoms. Some people don't exhibit symptoms as violently as others.
When
am I contagious?
You will be contagious as soon as the virus starts replicating itself, usually ten hours after exposure. (Note that it could be days before you even know you have a cold.) People are at their most contagious two to four days after exposure. This is because the virus has been growing unchecked. After four days your immune system kicks in and starts reducing the infection. However, you will remain contagious as long as you have cold symptoms.
Be aware that if you have a cold and wash your hands to avoid spreading it, you may infect the towel you dried your hands on and the virus particles may survive on it many hours. The next person who touches that towel, even if it's half a day later, could become contaminated.
How
can I avoid catching colds?
It's almost impossible. Washing your hands frequently when you are in a location where you know there are infected people will help, as will the more extreme measure of wearing a protective mask. The problem with these precautions is that they require that you know when you're around someone with a cold. As already mentioned, many people don't know they have one. Worse still, twenty-five percent of everyone who catches a cold never experience symptoms. No one knows why. They really are sick and have active cold viruses replicating in their throats but they never feel bad. They can pass this same cold on to you and it may almost kill you, but they will never know they were the source.
How
can I avoid passing a cold onto others?
Isolate yourself as soon as you feel a symptom. Better yet, isolate yourself for a few days if you know you've come in contact with someone who has a cold. Lock yourself in a room and have people feed you by passing food to you on the end of a long pole. Don't touch anything that someone else might come in contact with.
If you have a child with a cold, isolate them (from yourself as well as other school children) as soon as possible and keep them isolated as long as they have symptoms.
How
can I cure a common cold?
To date there is no know cure or preventative for the common cold. Zinc, echinacea, vitamin C, garlic, eucalyptus, honey, lemon, menthol, steam, hot toddies, alcohol, chicken soup and many other "cures" have been repeatedly tested and have been proven to not prevent or shorten the duration of a cold. At best they provide some physical relief which may comfort the afflicted. (Several times cold "remedies" have come out claiming to have scientific research supporting their claims. However, according to the sources listed above, upon peer review and repeated controlled tests none have proven to work.)
Why do so many people cling to the belief that one or more of these are effective? Because of the varied nature of colds. Some viruses only last a few days. Others wear on for weeks. Imagine a guy who is infected with a four-day form of cold. If he does nothing he will be well in four days. But, the second he starts to feel ill he drinks a gallon of orange juice. A couple of days later he feels great and tells everyone that the vitamin C in the juice killed his cold. This anecdote quickly spreads and everyone starts drinking orange juice. The vitamin C didn't cure it. He just got lucky. On the other hand, people who try some "cure" and find that it doesn't work aren't nearly as likely to report it. People don't like bragging about their failures, only their successes. So, human nature and the variability of the cold virus create a situation where beliefs in cold cures persist in spite of overwhelming scientific evidence to the contrary.
Why
can't someone make a medicine to cure the common cold?
There are so many different types of cold viruses and they are so varied in their nature that it's impossible to develop a single drug that would be effective against all of them. It's sort of like asking someone to develop a single bait for fishermen that with attract every type fish in the world. Each fish has it's particular tastes so one bait can't be made to work on them all.
Another consideration is that cold viruses can be tough. Something strong enough to knock them all down might be dangerous to the patient.
How
do I get over a cold?
After 2 to 4 days, the human immune system has had enough time to analyze the virus attacking the body and manufacture an antivirus to kill it. For the next several days the virus and antivirus are locked in a battle to the death. Fortunately, the body's immune system is stronger than any of the known cold viruses so we always win, it just takes a little time.
Drinking plenty of fluids and getting lots of rest will help you get over the cold as soon as possible.
How
often
will I catch a cold?
Adults average 2.5 colds a year. Elementary school children average 8 per year.
Can
I do anything to reduce the number of colds I get a year?
Besides avoiding contact with contaminated people, the only proven way to reduce the number of colds a person gets on average is daily aerobic exercise. No one knows why but it works.
Other things that seem to reduce the number of colds people get are eating a good diet, getting plenty (8 hours or more a day) of sleep, and leading a low stress life style. Again, none of the sites I visited could explain why.
What
is the principle source for colds?
Elementary schools. Children are commonly sent to school in spite of their having colds. They are then locked in a small room with 20 to 32 other children for 6 to 8 hours. They are also crowded shoulder to shoulder in auditoriums for lunch and assemblies. Under such conditions it's impossible for one sick child to avoid infecting dozens of others. They in turn take the cold home and expose their siblings and parents, who take it to their schools and work places. From there the cold spreads outward.
Day care centers and crowded offices are also prime sources for spreading colds.
Can
you
catch two colds at once?
Yes. If you are exposed to two different cold viruses they can both infect you at the same time. Worse still, if two viruses invade the same cell at the same time their DNA can blend to produce a new type of cold virus. Such mutations are likely the reason there are so many different types of cold viruses.
Why
can't someone make an immunization for cold viruses?
They can... and fairly easily too. It would be simple to build up a warehouse of antiviruses, one for every known cold virus. The problem is that if you got a cold no one would know which antivirus to give you. Most colds have such similar symptoms that telling one from another is impossible. This problem is further complicated by the fact that different people react to the same virus differently. The only way to figure out which antivirus to give you would be to take a sample of what you have, grow it, and test it to identify the particular strain that's making your life miserable. Even with modern testing techniques that would take a couple of weeks. By that time you're going to get well on your own.
Why not mix all the antiviruses together and give anyone with a cold a shot of it? Think back to the last time you had a flu shot. Odds are it involved injecting a cubic centimeter of liquid. If you had to have enough of each of the 300 cold antiviruses to cure you, it would require injecting 300 cubic centimeters of liquid into your blood stream. You arm would explode.
Okay, then why not inoculate everyone for all the different types of cold viruses? Because there are several hundred of them, which would require getting several hundred injections. How would you like to have to go to a doctor's office for a shot every other week for two or three years? How would you like dragging your children in for that sort of treatment? At $40 to $60 a shot, how are you going to like forking over the $2,000 per person a treatment like that would cost? Finally, even if you did all that there would still be new strains that might pop up to infect you.
Why
do I sometimes end up with a cough that lasts for weeks after the
cold is gone?
Every time a virus invades a cell in your throat that cell is killed. Let's say that each infected cell releases enough viral particles to invade 100 other cells.
Case 1: You get infected with a single virus particle that invades one cell. Ten hours later it replicates and you now have 100 infected cells, Ten hours more and you have 10,000 infected cells, then 1,000,000, then 100,000,000. A few days after the initial infection billions of your throat cells have been killed. Once you're over the cold these will take a little time to be replaced. Until then you might have a couple of days of scratchiness that persists after the cold is gone.
Case 2: Someone sneezes in your face at the same time you take a deep breath through your nose. Now you've been infected with millions of virus particles. They have a enormously greater numerical advantage than in case 1 and by the time your immune system beats them back, trillions of your cells would have killed and you can have significant damage to your mucus membranes that takes weeks to heal. During this time you might experience a persistent irritation and cough.
If
the cold virus is limited to my adenoidal area, why do I feel rotten
all over? Why does a cold cause general body aches?
That's one question none of the sites I visited could answer. I plan to ask my doctor this question next time I see him and will update this page with his answer.
(I'm just guessing but part of the problem may be that the immune system's response may tax the body's energy. Also, sinus pressure causes headaches which tend to make people feel achy, as does anything, like a scratchy throat, that continually irritates us.)
Will
having a weakened immune system increase my chances for getting a cold?
All of the sources I reviewed said, "No." A weak immune system might slow your body's ability to fight off the cold once you have it but it won't increase the odds of your catching one. Another way to word this is that having a strong immune system won't prevent you from catching a cold. The best it can do is help you get over it faster.
This makes sense because the immune system is an after-the-fact system. It can't go to work until after there is an infection for it to analyze and attack. The one exception to this would be if you previously had this particular cold virus and your immune system already had antibodies in place to fight it.
Should
I feed or starve a cold?
It doesn't matter. Neither technique seems to effect colds, although starvation to the point of ill health could cause other problems. Also, avoiding milk or drinking lots of it doesn't seem to matter.
What
about germicidal
lotions and soaps?
The sources I read indicated that they don't seem help.
What
about antibiotics?
Antibiotics only work on bacteria. Colds are caused by viruses, which aren't affected by antibiotics.
That's it!
I found it frustrating that I couldn't discover anything to prevent colds or at least help me get over them. But, learning what they are and how they work will at least give me the comfort of knowing what it is that's making me so miserable next time I catch one. I sincerely hope that you enjoyed this page, found it interesting, and that you never catch a cold again.
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