ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

The Common Cold

Updated on November 20, 2016
Source

Defense Systems

Though the average person gets two to three head colds in a season, she or he is not infected with the same virus more than once. Why are the symptoms of a cold remarkably similar every time? To answer this question we must first look at the body’s defense systems. The human body has three lines of defense against disease-causing pathogens. The first line of defense consists of barriers, such as skin and mucous membranes, which physically prevent pathogens from entering the body. The second line of defense is composed of various nonspecific cellular activities involving interferons, plasma proteins that form the complement system, natural killer cells (one kind of white blood cell), phagocytes (scavenger cells that consume cellular debris), and the inflammatory response. Both of these lines of defense involve nonspecific resistance, that is, they operate in the same manner regardless of the type of pathogen involved (Postlethwait and Hopson, 2003).

Rhinoviruses

The common cold is caused by one of over 200 different viruses. Rhinoviruses are one of the more common viruses and account for 30 to 35 percent of all colds affecting adults (National Institute of Allergy and Infectious Diseases, 2001). Cold symptoms are universally similar because of the effects of the human body’s nonspecific resistance to disease. A rhinovirus usually enters the nasal passage and breaches the body’s first line of defense by entering through the nasal membrane. The virus takes over local cells in the nasal membrane and causes them to replicate more virus cells. Eventually some of the nasal membrane cells burst and die, releasing inflammation mediators that stimulate the body’s inflammation response. Inflammation mediators are composed of complement proteins, prostaglandin hormones, and cytokine proteins. These mediators direct phagocytes to the effected area to attack the virus and remove cellular debris (Postlethwait and Hopson, 2003).

Histamine and Heparin

Inflammation mediators also cause mast cells located in the mucous membranes and the connective tissue of the dermis to release histamine and heparin. Histamine attaches to local capillaries causing them to dilate and leak, which produces swelling, redness, and nasal congestion. (Many cold medications contain antihistamines that are designed to limit the inflammatory effects of histamine). Heparin binds to AT3 (a protein that inhibits blood clotting) to reduce the likelihood of the formation of a blood clot. Additionally, inflammation mediators cause mucous glands to secrete more mucous to flush away debris, which in turn causes the familiar cold symptoms of coughing, sneezing, and nose blowing. Mucus secretion is also stimulated by prostaglandins, which also cause bronchiole constriction, and elevated body temperature. Cytokines are usually responsible for producing inflammation in the throat (Postlethwait and Hopson, 2003).

Can you get the same cold more than once?

See results

Never the Same Cold Twice!

The good news about having a cold is that you will most likely never get sick from the same cold virus again. This happens because of the immunologic memory of the body’s immune system. The body makes antibodies to fight disease pathogens within the body, but it keeps a blueprint of how to make these antibodies. When a disease enters the body, the immune system determines if it is a new or previously encountered pathogen. If it is new, the body learns how to make antibodies to fight the new pathogen, and then releases the antibodies to do their work. If the body has already encountered the disease pathogen sometime in the past, the immune system releases antibodies that it already has to fight the disease, and starts to mass-produce more of the same antibody. In this case, the disease cannot get a foothold in the body and we do not get sick (Postlethwait and Hopson, 2003).

References

National Institute of Allergy and Infectious Diseases. (2001). Health Matters: The Common Cold. Bethesda, MD: author. Retrieved on May 19, 2004, from http://www.niaid.nih.gov/factsheets/cold.htm

Postlethwait, J. and Hopson, (2003). Explore Life. Pacific Grove, CA: Brooks/Cole.

Comments

    0 of 8192 characters used
    Post Comment

    No comments yet.

    working

    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, hubpages.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://hubpages.com/privacy-policy#gdpr

    Show Details
    Necessary
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Features
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Marketing
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Statistics
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)