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Author Topic: Why are colds commoner during periods of cold weather?  (Read 5240 times)

Johann Mahne

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People often say that colds occur more in winter because people spend more time indoors with closed windows and doors so that viruses stay suspended in the air for longer periods.This is not a bad theory.
  I was wondering if the colder air passing over mocous membranes somehow causes antibodies to be less active,and so gives viruses better conditions to get established?
« Last Edit: 31/07/2011 23:07:09 by chris »


 

Offline grizelda

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Re: Why are colds commoner during periods of cold weather?
« Reply #1 on: 18/07/2011 22:47:28 »
I doubt that antibody protection extends to the mucus, it's function seems to be to trap invading particles so they don't get into more sensitive areas. One new-age theory posits that an excess of protein in the diet leads to trapped denatured amino acids which form a mucus which organisms can reproduce in without interference from antibodies and from there can invade the body in quantities which overwhelm the system initially. I haven't had a cold in 30 years.
 

Offline CliffordK

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Re: Why are colds commoner during periods of cold weather?
« Reply #2 on: 19/07/2011 06:55:18 »
I've always thought physical stress was also a factor.  People talk about catching a cold because one stayed outside in cold/wet weather.  While the rain may not be a factor, associated stress could be.

As far as antibodies.  I believe each flu virus you get is a unique virus, and the same may be true with the cold.  You will certainly have some general antibodies, but you may not have antibodies to the particular strain you are being exposed to.

 

Johann Mahne

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Re: Why are colds commoner during periods of cold weather?
« Reply #3 on: 27/07/2011 18:41:47 »

I have just found these answers in Wikapedia.
Quote
I doubt that antibody protection extends to the mucus,
Antibodies do exist in mucous membranes.
Quote
You will certainly have some general antibodies, but you may not have antibodies to the particular strain you are being exposed to.
Antibodies function as a tagging service.They learn the shape of viruses and mark them for killer t cells

  So my question still remains...
 

Offline iko

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Re: Why are colds commoner during periods of cold weather?
« Reply #4 on: 31/07/2011 10:56:39 »
Vitamin D fanatics  ;) support the theory that you get symptomatic viral infections (colds, flu)
during the cold season, when your vitamin D levels are the lowest of the year.
Cholecalciferol or vitamin D3(It's not a real vitamin, 'cause we get less than 10% from the diet)
is activated to 1.25OH-vit.D, binds a specific cell receptor VDR, modulating the expression of 200-400 genes.
One action recently described is the synthesis of an antibiotic peptide called cathelicidin, that allows
white cells to inactivate intracellular pathogens (viruses, mycoplasmas, TB etc.).
"...further studies are needed to confirm..."
So much for anti-influenza vaccination campaigns!

Ikod
 

Offline BenV

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Re: Why are colds commoner during periods of cold weather?
« Reply #5 on: 31/07/2011 21:26:43 »
Cold air is likely to be less humid, which may have the effect of drying out the mucus and making it less efficient at removing unwanted material.
 

Offline iko

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Re: Why are colds commoner during periods of cold weather?
« Reply #6 on: 31/07/2011 22:42:35 »
Hi influential folks!

Did anybody check this out?


Enjoy more on vitamindcouncil.com...

ikod





This is a virology issue, specific for Prof. Chris.

I may give my contribution here by citing
an old discussion about influenza epidemics
and Dr. Edgar Hope-Simpson's 'seasonal stimulus'...
But this really is another story!
 
ikod   [^]


Talking of 'revisiting' and looking backwards,
allow me a cut&paste from Complementary Medicine
(Cod Liver Oil topic) and final comment from the
discussion in "Epidemic influenza and vitamin D"
J.J. Cannell et al. 2006.

Quote
Revisiting Vitamin D in humans.
just a few clever minds got this point
first, several years ago...



A hypothesis concerning deficiency of sunlight,
cold temperature, and influenza epidemics associated with
the onset of acute lymphoblastic leukemia in northern Finland.


Timonen TT.

University of Oulu, Department of Internal Medicine, Kajaanintie 50, FIN-90220 Oulu, Finland.

Research to detect new factors contributing to the etiology of acute leukemia (AL) is urgently needed. Located between latitudes 65 degrees and 70 degrees north, the population in northern Finland is exposed to extreme seasonal alterations of ultraviolet-B light and temperature. There is also a seasonal variation of both the 25(OH)- and 1,25(OH)2-D3 vitamin serum concentrations. In the present work, the frequencies of different types and age-groups at diagnosis of AL were compared during the dark and light months of the year, to uncover seasonality. Between January 1972 and December 1986, 300 consecutive patients aged >/=16 years and diagnosed as having AL were enrolled. The observed mean monthly global solar radiation, temperature measurements, and influenza epidemics were compared with the monthly occurrence of AL. Both acute lymphoblastic leukemia (ALL) (p=0.006) and total AL (p=0.015) were diagnosed excessively in the dark and cold compared with light and warm period of the year. There was a tendency for de novo leukemia to increase also in the dark and cold, but for acute myeloid leukemia (AML) patients the excess was not significant. Age >/=65 was strongly associated with the dark and cold season (p=0.003). Significantly more ALL (p=0.005) and de novo leukemias (p=0.029) were observed during influenza epidemics than during nonepidemic periods. However, a seasonality, i. e., the fluctuation of numbers of AL cases, was not determined, either monthly or during different photo- and temperature periods or influenza epidemics; this might be due to the small numbers of patients studied. Nevertheless, it is hypothesized that sunlight deprivation in the arctic winter can lead to a deficiency of the 1, 25(OH)2D3 vitamin, which might stimulate leukemic cell proliferation and block cell differentiation through dysregulation of growth factors in the bone marrow stromal cells, causing one mutation and an overt ALL in progenitor cells damaged during the current or the previous winter by influenza virus, the other mutation.

Ann Hematol. 1999 Sep;78(9):408-14
.




Epidemic influenza and vitamin D.

Cannell JJ, Vieth R, Umhau JC, Holick MF, Grant WB, Madronich S, Garland CF, Giovannucci E.
Atascadero State Hospital, 10333 El Camino Real, Atascadero, CA 93422, USA. jcannell@dmhash.state.ca.us

In 1981, R. Edgar Hope-Simpson proposed that a 'seasonal stimulus' intimately associated with solar radiation explained the remarkable seasonality of epidemic influenza. Solar radiation triggers robust seasonal vitamin D production in the skin; vitamin D deficiency is common in the winter, and activated vitamin D, 1,25(OH)2D, a steroid hormone, has profound effects on human immunity. 1,25(OH)2D acts as an immune system modulator, preventing excessive expression of inflammatory cytokines and increasing the 'oxidative burst' potential of macrophages. Perhaps most importantly, it dramatically stimulates the expression of potent anti-microbial peptides, which exist in neutrophils, monocytes, natural killer cells, and in epithelial cells lining the respiratory tract where they play a major role in protecting the lung from infection. Volunteers inoculated with live attenuated influenza virus are more likely to develop fever and serological evidence of an immune response in the winter. Vitamin D deficiency predisposes children to respiratory infections. Ultraviolet radiation (either from artificial sources or from sunlight) reduces the incidence of viral respiratory infections, as does cod liver oil (which contains vitamin D). An interventional study showed that vitamin D reduces the incidence of respiratory infections in children. We conclude that vitamin D, or lack of it, may be Hope-Simpson's 'seasonal stimulus'.

Epidemiol Infect. 2006 Dec;134(6):1129-40. Epub 2006 Sep 7.




...from the final conclusion in the full-text:

  Today, in a rush from multiplex reverse transcriptase-polymerase chain reactions that rapidly subtype influenza viruses to complex mathematical formulas that explain infectivity, many of us have forgotten Hope-Simpson's simple 'seasonal stimulus' theory for the lethal crop of influenza that sprouts around the winter solstice.   The faith and humility that characterized his life and his writings insulated him from despairing that his 'seasonal stimulus' would not be sought.  Among his last published words was the suggestion that 'it might be rewarding if persons, who are in a position to do so, will look more closely at the operative mechanisms that are causing such seasonal behaviour' [3,p.241].



A Gloucestershire GP carefully recorded the incidence of influenza in his practice over a period of nearly 30 years. Dr Hope-Simpson obtained a picture of the timing and intensity of these cases from 1946 to 1974.
Is it possible to compare Kilbourne’s chronological model of the spread of influenza with this data?
Such a comparison indicates that there should be evidence of the following factors influencing the final picture:
- A distinct seasonal pattern, with the highest incidence in winter.
- A series of decreases in the size of epidemic waves as the population becomes immune to one particular strain of the virus.
- The appearance of a new strain with changed antigens, meaning that the body’s defence mechanism does not recognise it. The whole process of infection should then begin again.
- The presence of more than one strain of influenza in the population at any one time.
- Newly introduced strains from other parts of the world, which can be especially virulent.

for more reading click here:  http://www.makingthemodernworld.org.uk/learning_modules/geography/05.TU.01/?section=6





 

Offline cheryl j

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Why are colds commoner during periods of cold weather?
« Reply #7 on: 16/11/2011 02:11:57 »
The explanation they always give is that people are in doors more in the winter, touching the same objects, coughing on each other, but if that is true, does no one in Florida ever get a cold? There has to be more to it. Also, was the cold and flu cycle the same before the invention of the standard school year with months off for summer? Is it different where people have year-round-school?
 

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Why are colds commoner during periods of cold weather?
« Reply #7 on: 16/11/2011 02:11:57 »

 

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