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What is a Cold? Virus or Bacteria?

written by: Andrea Campbell • edited by: Carly Stockwell • updated: 8/25/2014

A virus is so efficient, only 24 hours after a single virus particle enters your nose, you’re sick! Learn about causes, symptoms and remedies for the common cold.

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    Cold: Virus or Bacteria? You get a scratchy throat and it’s like a wool rug rubbing open skin. In 8 to 12 hours, the virus you picked up will complete its reproductive cycle–the incubation period. Viruses bully infected cells into making millions of new viruses, bent on infecting other healthy cells. The misery begins at 12 hours and typically peaks around 48 to 72 hours.

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    …It Was the Worst of Times

    You will encounter cold viruses about 200 times in your lifetime. We can calculate that as five years of congestion, coughing, sore throat and headache—or one full year in bed that you won’t get back.

    Why do we use the word cold? Is it because we get it in times of chilliness, in winter or when we get wet? No, being cold does not a cold make. There is a word for the common cold in every language: Italian is raffreddore, in Latin it is frigidus and Germans say erkältung. You get the idea; it’s a universal pest.

    Why are some colds long and feel as though they are set into our bones going on for days, when others are just irritating with a little snuffle here and a minor headache there? Why do some people seem resistant to getting cold viruses while others seem doomed to tissue overload and days on the couch?

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    Day Care is the Pits

    Children have been called the “major reservoirs of colds" and for good reason! Children get sick a lot. Daycare is like a Petri dish. Germs are efficient there, dripping off a child’s nose, riding the wind on the end of a sneeze or coughing over a commonly held toy. Since children share such close quarters, almost never use a Kleenex and don’t know the ins and outs of sickness, childcare centers become swapping grounds for colds.

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    Money and Time Lost

    American medicine cabinets hold as many as eight cold remedies.

    Jennifer Ackerman, author of the book, Ah-choo: The Uncommon Life of Your Common Cold estimates there are a 100 million doctor’s visits per year and 1.5 million emergency visits for the cold. The absence of work because of colds has cost the economic community in the U.S. 60 billion dollars in a single year. Half of all school illnesses are due to the common cold with over 189 million school days missed.

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    A weakened immune system or being “run down" is not a precursor to a cold. In addition, you may not want to boost your immune system while you have a cold. That is counter-productive, says Jack Gwaltney Jr., professor emeritus with the University of Virginia School of Medicine. In fact, it can actually increase your suffering.

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    How Common?

    The common cold represents over 200 different viruses.

    There is a name for people who are infected with a virus but never suffer symptoms: Asymptomatic infection. They won’t endure and the kicker is that they still make anti-bodies. Why? No one really knows.

    Do you want to catch a cold virus for money? (Thousands of research subjects have.) To catch one, put a contaminated finger into your nose or rub an eye with dirty hands.

    Just a tiny smack of rhinovirus is enough to give you an infection. Cold viruses can even travel down the lacrimal (tear) duct from the eye into the nose.

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    The Body Guardian

    The thick sticky mucus in your nose lining traps viruses and other foreign particles before they enter the lungs. That’s good.

    Generally, dust, pollen and other particles can be swept into the back of the throat to be swallowed and killed by stomach acid. Also good.

    Sir William Osler, a Canadian physician who advanced medical science by putting students into both clinical and lab work, said that sometimes virus particles ride the tiny hairs from the nose into the “garbage dump" in the back of the throat. There, the miniscule invaders glom onto body cells a thousand times their size and hitch a ride, pretending to be something they are not. They fit like a lock falling into a key, adjusting themselves into the ICAM-1 receptors and docking there to begin their havoc.

    If you are lucky enough to have had this strain before, protective antibodies will guard against it. The antibodies neutralize the viral particles by binding to their surface and hampering their ability to slip into a cell and release a piece of itself into RNA or genetic material.

    However, viruses’ only goal is to multiply. They depend on an organism’s host to replicate. They have no cell; they are acellular. When attacked and hitched, so-to-speak, the body cell starts to destroy itself and fresh virus particles release to infect surrounding cells.

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    Bacteria Defined

    Bacteria are not all good or all bad. There are different types.

    Bacteria are single-celled microorganisms and reproduce asexually, just like other cells. This means they reproduce by splitting into two cells, making an exact copy—a perfect twin.

    Bacteria are good in yogurt. They’re bad in Clostridium perfringens: a bacterium that is the most common cause of gangrene. It infects soft tissue and muscle by producing gas and toxins. Before antibiotics were discovered, many battlefield injuries resulted in gangrenous amputations. It is also a source of food poisoning, such as when meat is poorly prepared.

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    Antibiotic Trap

    An antibiotic has no effect on viral colds. Typically, antibiotics are supposed to kill bacteria by preventing them from building cell wall, but viruses ARE NOT cells. Viruses have no cell walls, so they are unaffected by drugs. To wit, anti-bacterial soaps have no effect on viral cold germs, despite what you read on labels or advertising. In fact, research has shown they are no more effective than regular soap.

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    Pass Me the Virus

    Viruses are typically spread by hand. Cold viruses can remain viable on inanimate objects and surfaces. Rhinovirus, which is largely nasal secretions, will remain live on the skin for at least two hours.

    Inanimate objects can serve as passive carriers of contagions so a keyboard, doorknob or elevator button can transfer germs when contaminated with body secretions, droplets from sneezing, or virus-laden soiled hands, and they can live a surprisingly long time even if they can’t reproduce while waiting. They need your touch to be transported from surface to nose.

    A recent study says that students generally touch their hands to eyes, nose and lips 16 times an hour

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    Factoid Surprise

    Green mucus is not a sign of bacterial infection but rather a mighty immune response as more and more white blood cells (polys) are recruited to the nose, carrying iron-containing enzymes.

    Researchers have found aspirin and acetaminophen can suppress certain immune responses and increase nasal stuffiness in adults.

    Researchers call an unguarded sneeze, a “sanitary crime" because aerosolized microbial particles can travel 150 feet per second and a distance of more than 10 feet. They are best with passing influenza virus. Travel by plane has been a dandy culprit of this type of transmission.