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  • Pathogens & People: Do these 4 things and you might avoid the common cold

    Source: http://www.hometownannapolis.com/cgi...8/12_07-31/LIF

    Pathogens & People: Do these 4 things and you might avoid the common cold

    By EDWARD McSWEEGAN, For The Capital
    Published December 07, 2008

    The cold and flu season is almost upon us.

    We worry about the flu and many of us will take the annual vaccine and try to avoid people who may have the flu. Colds, on the other hand, are viewed as mild irritants. Colds are just a few days of scratchy throats, running noses, coughs and maybe some mild fever. There's not much to do about a cold and not much to worry about either.

    Or is there?

    Last year, the Centers for Disease Control and Prevention reported 140 cases of an unusually severe type of cold. Five percent of the patients died.

    The "common cold" is caused by hundreds of common viruses. Most colds are caused by a group of viruses called rhinoviruses. Coronaviruses, parainfluenza viruses, adenoviruses, enteroviruses and some influenza viruses also can cause colds.

    There are about 50 types of adenoviruses that infect people. The adenoviruses are very hardy and can survive outside a human host long enough to be picked up by another unlucky victim. Some of these adenoviruses are able to cause persistent, but asymptomatic, infections of the tonsils and intestines. Still others are able to cause bronchitis, pneumonia and a sometimes fatal respiratory illness.

    One of these 50 adenovirus types is called Ad14 or serotype 14. This is the killer cold virus that was identified by CDC as the cause of outbreaks in four states in 2007. Ad14 was first seen among military recruits in 1955, but since then has rarely been seen in the U.S. So the 2007 outbreaks may represent the emergence of a new and virulent strain of Ad14.

    Newborns, the elderly and people with compromised immune systems would be the most susceptible to a new and virulent cold virus. The cells of the nose and throat seem to be the primary targets of viral invasion. The virus triggers local inflammation and the production of immune regulators such as interferon. These immune response molecules in turn trigger most of the unpleasant symptoms of a cold: headache, malaise, fatigue, nausea, congestion and painful sinuses. Over-the-counter medications don't seem to help much, and antiviral drugs such as ribavirin and cidofovir don't seem to be very effective against adenoviruses.

    The emergence of a new and more virulent Ad14 virus could be especially bad news for the military. New recruits - crowded together in barracks and under the 24 / 7 stress of boot camp - are ideal candidates for acquiring and spreading adenovirus infections. The lost training time and medical costs from adenovirus infections encouraged the Defense Department to fund work on vaccines against two of the more common culprits, Ad7 and Ad4. An effective combination vaccine was produced and given to millions of new recruits, but disputes with the manufacturer led to the end of the military vaccination program in 1999. The following year, the Institute of Medicine recommended the immediate re-establishment of an adenovirus vaccine supply. Now, eight years later, Barr Labs in Virginia soon may be in a position to begin offering a new oral vaccine against Ad4 and Ad7 adenoviruses.

    There is no vaccine for Ad14.


    The common cold, and some of the uncommon causes of those colds, present unique challenges to both patients and physicians. There are too many viruses, too little understanding of how they spread and cause disease, too few effective medicines and even fewer available vaccines.

    Worse yet, your mother may have been right all along. Remember her telling you to put on a sweater or jacket "so you don't catch a cold''? In response, you may have wisely insisted that you couldn't get a cold from being cold. Well, maybe you do.

    According to an article in New Scientist, researchers in the United Kingdom found more people developed colds after they became chilled. Cool temperatures prompt the body to redirect blood flow inward, including away from the nasal passages. The change in blood flow and nasal temperature may make it easier for viruses to enter via the nose. So mom may have been right again. I can already hear the "I told you so's."

    In the end, the best way to avoid a cold - and Ad14 - may be to keep your nose warm, wash your hands regularly, avoid small children and listen to your mother.

    ---

    Dr. Edward McSweegan has a Ph.D. in microbiology and lives in Crofton. He works on and writes about infectious disease issues. He may be contacted at mcsweegan@nasw.org.

  • #2
    Re: Pathogens & People: Do these 4 things and you might avoid the common cold

    According to an article in New Scientist, researchers in the United Kingdom found more people developed colds after they became chilled. Cool temperatures prompt the body to redirect blood flow inward, including away from the nasal passages. The change in blood flow and nasal temperature may make it easier for viruses to enter via the nose.
    I'd be curious to see this research paper.
    The salvage of human life ought to be placed above barter and exchange ~ Louis Harris, 1918

    Comment


    • #3
      Re: Pathogens & People: Do these 4 things and you might avoid the common cold

      keep your nose warm
      wash your hands regularly
      avoid small children
      listen to your mother

      According to an article in New Scientist, researchers in the United Kingdom found more people developed colds after they became chilled.

      must be this:
      http://fampra.oxfordjournals.org/cgi.../full/22/6/608


      13/90 subjects who were chilled reported they were suffering from a cold [with]in the 4/5 days...
      compared to 5/90 control subjects
      There was no evidence that chilling caused any acute change in symptom scores

      The subjects who reported that they developed a cold (n = 18) reported that they suffered
      from significantly more colds each year compared to those subjects who did not develop a cold (n = 162).

      -----------------------------------------------------------

      on cooling the feet, 6/8 experienced tingling, soreness or dryness in their throat, or tingling, stuffiness or dripping from their nose.

      2/29 of cystitis prone women noted soreness in their throat and/or a dry cough, and none noted any symptoms from their nose
      Symptoms lasted 1-4 hours, and were not followed by upper respiratory infections

      .----------------------------------------

      Latest research: In a new study, Claire Johnson and Ronald Eccles of Cardiff (Wales) University's Common Cold Centre intended to show that chilling the feet sometimes causes symptoms of the common cold. The experiment randomly divided 180 people into two groups. (So far, so good.) Half put their feet in a pot of cold water for 20 minutes, and the other half put their feet in an empty pot for 20 minutes. (Less good, since it would be no secret which group a subject was placed in.) Four or five days later, the participants were mechanically tested by a machine that measured stuffed-up-ness. (Good.)

      Results: But the objective measurements were too varied to provide meaningful data and, accordingly, were not considered when the data were analyzed. (Uh-oh.) Instead, the subjects, fully aware of the group to which they had been assigned, kept diaries in which they recorded their subjective sense of whether they were experiencing cold symptoms. (Double uh-oh.) Thousands of experiments have demonstrated just how easily subjects are influenced by expectations when they make subjective judgments. I have little doubt that this study, which claimed to find a connection between chilled feet and cold symptoms, is just one more example. It wouldn't have helped much, but couldn't the researchers at least have counted Kleenex?
      http://www.slate.com/id/2137093/
      I'm interested in expert panflu damage estimates
      my current links: http://bit.ly/hFI7H ILI-charts: http://bit.ly/CcRgT

      Comment


      • #4
        Re: Pathogens & People: Do these 4 things and you might avoid the common cold

        Antihistamines are useless against the common cold:
        http://www.ncbi.nlm.nih.gov/pubmed/1...ubmed_RVDocSum

        Inhalation of cold, dry air significantly reduced the temperature of the septal mucosa at each location of measurement compared to the breathing of ambient air. Inhalation of hot, humid air significantly increased the septal mucosal temperature at all detection sites
        http://www.ncbi.nlm.nih.gov/pubmed/14575401?ordinalpos=1&itool=EntrezSystem2.PEntrez. Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.P ubmed_Discovery_RA&linkpos=4&log$=relatedarticles& logdbfrom=pubmed


        1: Rhinology. 2002 Sep;40(3):109-14. Links
        Acute cooling of the body surface and the common cold.
        Eccles R.
        Common Cold Centre, Cardiff School of Biosciences, Cardiff University, United Kingdom. eccles@cardiff.ac.uk
        There is a widely held belief that acute viral respiratory infections are the result of a "chill" and that the onset of a respiratory infection such as the common cold is often associated with acute cooling of the body surface, especially as the result of wet clothes and hair. However, experiments involving inoculation of common cold viruses into the nose, and periods of cold exposure, have failed to demonstrate any effect of cold exposure on susceptibility to infection with common cold viruses. Present scientific opinion dismisses any cause-and-effect relationship between acute cooling of the body surface and common cold. This review proposes a hypothesis; that acute cooling of the body surface causes reflex vasoconstriction in the nose and upper airways, and that this vasoconstrictor response may inhibit respiratory defence and cause the onset of common cold symptoms by converting an asymptomatic subclinical viral infection into a symptomatic clinical infection.


        ----------------------------------------------------------------

        1: Int J Tuberc Lung Dis. 2007 Sep;11(9):938-43. Links
        Exposure to cold and respiratory tract infections.Mourtzoukou EG, Falagas ME.
        Alfa Institute of Biomedical Sciences, Athens, Greece.

        There is a constant increase in hospitalizations and mortality during winter months; cardiovascular diseases as well as respiratory infections are responsible for a large proportion of this added morbidity and mortality. Exposure to cold has often been associated with increased incidence and severity of respiratory tract infections. The data available suggest that exposure to cold, either through exposure to low environmental temperatures or during induced hypothermia, increases the risk of developing upper and lower respiratory tract infections and dying from them; in addition, the longer the duration of exposure the higher the risk of infection. Although not all studies agree, most of the available evidence from laboratory and clinical studies suggests that inhaled cold air, cooling of the body surface and cold stress induced by lowering the core body temperature cause pathophysiological responses such as vasoconstriction in the respiratory tract mucosa and suppression of immune responses, which are responsible for increased susceptibility to infections. The general public and public health authorities should therefore keep this in mind and take appropriate measures to prevent increases in morbidity and mortality during winter due to respiratory infections.


        ------------------------------------------------------------
        I'm interested in expert panflu damage estimates
        my current links: http://bit.ly/hFI7H ILI-charts: http://bit.ly/CcRgT

        Comment


        • #5
          Re: Pathogens & People: Do these 4 things and you might avoid the common cold

          n=81
          signs were cough and sneezing, symptoms were nasal congestion and runny nose
          feverishness and headache, were each reported in 15% of children at onset
          73% were still symptomatic after 10 days
          Rhinovirus was detected in 46%
          bacterial pathogens (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis)
          were detected in 29% of episodes
          http://www.ncbi.nlm.nih.gov/pubmed/18162930?ordinalpos=1&itool=EntrezSystem2.PEntrez. Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.P ubmed_Discovery_RA&linkpos=2&log$=relatedarticles& logdbfrom=pubmed

          --------------------------------------------------------------
          They found that the virus lingers on more than a third of the objects touched by someone who has a cold. An hour after an infected droplet is deposited by an unwashed hand, it has a 60 percent likelihood of being transmitted to the next person who comes into contact with it.
          The researchers noted that the rhinovirus can stick around waiting to infect its next victim as long as 24 hours after being deposited onto a surface, when it might be picked up a third of the time.
          Not surprisingly, children are more likely to spread the cold virus than adults, and they are much more likely to catch colds. In the US, children experience colds about seven to 10 times a year, while adults typically have two colds a year.
          ----------------------------------------------
          Echinacea Found Useless in Cold Study (28 Jul 2005)
          Vitamin C May Not Have Much Effect on Colds (28 Jun 2005)
          Ginseng-Based Product Effective Against Common Cold (25 Oct 2005)
          Antibiotics Useless for Common Cold (22 Jun 2005)
          -------------------------------------------
          I'm interested in expert panflu damage estimates
          my current links: http://bit.ly/hFI7H ILI-charts: http://bit.ly/CcRgT

          Comment


          • #6
            Re: Pathogens & People: Do these 4 things and you might avoid the common cold

            http://www.cardiff.ac.uk/biosi/subsi...ommoncold.html

            Young children represent the main reservoir of common cold viruses and infection usually occurs at home or in the nursery or school. Adults with regular contact with children are most exposed to infection.

            Under laboratory conditions when healthy volunteers are kept with others who are suffering from common cold infections it has proven remarkably difficult to spread infection from one person to another 2.

            There is much evidence that indicates that the stress of every day life can influence the susceptibility to infection

            Bradykinin is important

            A dry scratchy sore throat is often the first sign of a common cold and this may be due to the virus first infecting the back of the nose15

            Fever associated with common cold is uncommon in the adult but quite common in infants and children.


            ---------edi1-------------
            > In the vast majority of cases the infection will resolve in 4-7 days with or without treatment

            contradicts the article, where most people were still symptomatic on day 10

            > dextromethorphan and codeine there is very little evidence to support their effectiveness
            > in treating cough associated with common cold

            I had seen other claims

            > In the USA it is estimated that the annual economic burden of common colds through lost
            > working days etc. is around $5 billion

            > Recent research indicates that early treatment of common cold with zinc lozenges may
            > shorten the duration of common cold symptoms by several days. However, there are several
            > clinical trials that have reported that zinc lozenges are no more effective than placebo medicines.
            > The difference between clinical trials may be related to different formulations of zinc lozenge.

            > PLECONARIL
            I'm interested in expert panflu damage estimates
            my current links: http://bit.ly/hFI7H ILI-charts: http://bit.ly/CcRgT

            Comment


            • #7
              Re: Pathogens & People: Do these 4 things and you might avoid the common cold

              Inhalation of cold, dry air significantly reduced the temperature of the septal mucosa at each location of measurement compared to the breathing of ambient air. Inhalation of hot, humid air significantly increased the septal mucosal temperature at all detection sites
              I find this all slightly confusing. Maybe the nose temperature isn't even important?

              When we go out into the cold, our noses tend to drip, which I thought was our body's way of washing the germs out.
              The salvage of human life ought to be placed above barter and exchange ~ Louis Harris, 1918

              Comment


              • #8
                Re: Pathogens & People: Do these 4 things and you might avoid the common cold

                Abstract
                Rhinoviruses are epidemiologically connected to the majority of acute asthma exacerbations; however, their ability to infect and replicate in the lower airways is disputed. A frequent argument against this possibility involves the temperature preference for rhinovirus replication, generally accepted to be 33C, the temperature of the nasal passages. However, this argument is based on studies with a single rhinovirus serotype. In this study, differences in temperature preferences were evaluated between several serotypes and relative titers were determined than can be achieved at upper and lower airway temperatures. Rhinovirus serotypes 1b, 2, 7, 9, 14, 16, 41, and 70 were titrated in Ohio-HeLa cell cultures at either 33C or 37C. Possible selection by culture temperature was examined by continuous culture at 33C and 37C for 2-4 passages and subsequent titration at both temperatures. Finally, nasal aspirate samples derived from patients with wild-type rhinoviral common colds were cultured at 33C and 37C and RT-PCR was used to assess rhinovirus replication at each temperature.

                Results:
                The majority of the serotypes and wild-type viruses replicated slightly better at 33C (91.4 F)than at 37C (98.6). However, titers achieved after one or more replicative cycles at 37C were still high enough to initiate infection. Furthermore, in some instances equal or even better replication was observed at 37C. It is concluded that temperature preferences may vary between rhinoviruses and are not likely to be a prohibitive factor for infection of the lower airways. J. Med. Virol. 58:100-104, 1999. 1999
                http://www3.interscience.wiley.com/j...TRY=1&SRETRY=0
                The salvage of human life ought to be placed above barter and exchange ~ Louis Harris, 1918

                Comment


                • #9
                  Re: Pathogens & People: Do these 4 things and you might avoid the common cold

                  Originally posted by mixin View Post
                  I find this all slightly confusing. Maybe the nose temperature isn't even important?

                  When we go out into the cold, our noses tend to drip, which I thought was our body's way of washing the germs out.
                  They need to define "cold". When it's extremely cold, the severe cold can kill some pathgens. When it's cold enough that your nose hairs freeze instantly, I think the germs die before they can infect.

                  .
                  "The next major advancement in the health of American people will be determined by what the individual is willing to do for himself"-- John Knowles, Former President of the Rockefeller Foundation

                  Comment


                  • #10
                    Re: Pathogens & People: Do these 4 things and you might avoid the common cold

                    Freezing nose hairs = pretty cold, that's for sure

                    I was surprised by this:
                    The "common cold" is caused by hundreds of common viruses. Most colds are caused by a group of viruses called rhinoviruses. Coronaviruses, parainfluenza viruses, adenoviruses, enteroviruses and some influenza viruses also can cause colds.
                    The salvage of human life ought to be placed above barter and exchange ~ Louis Harris, 1918

                    Comment

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