[Karen W. (OP)]

I know one does not catch a cold from weather conditions, but from viruses etc.. But can one worsen and already existing cold through exposure to cold wet damp weather?  Does your immune system being comprimised already by a virus make you more suseptible to weather conditions..?? I hope that question makes since.. As I have tons of parents who bundle their children to the point of heat exhaustion when the sun is out and there is any nip in the air.. The children are hot, running around but we have parents who insist they wear these large quanities of clothing when the child can normally tell and will ask when they are cold.. It's a dilima, I always heard the weather was not how one recieved a cold, but does it infact worsen one who has already had a comprimised immune system...?

[neilep]

I have always struggled with this. How does temperature give you a cold ?

is it merely that if you're cold then you may be more vulnerable to the germ ?

Tepmereature is...well...'temperature ' ...it's not a cold germ !!

me wants to know too.

[Karen W. (OP)]

I think you get the germ or bug first, this comprimises your immune system and then, I think you may or may not be more suseptible to the cold weather etc.. It confuses me..

[iko]

Hi N&K frantic sleepless poster Masters!

Nothing is simple!
Germs are all around, most of them kept under control by our defense
(call it immune system, to sound smart!).
Multiple factors contribute to this steady-state (objective health):

-Your Genetics (mum&dad,grampa&granny)
-Your previous exposure to germs and production of specific defence
-State of tuning of the Defence system itself (Diet and exercise)
-Type/strain, number and vitality of the presenting Germs
-Temperature!

Defense systems work at their best when body temperature is optimal.
Enzymes and cofactors, bug-eating cells (macrophages), need a proper
temperature to do their job and stop an invasion by 'alien' germs.
Sometimes fever and shivers are needed to speed them up and force
the owner of the body to stop and look for a warm place (silly dude!).

In the old days, before our Antibiotic Age, losing the battle in those
initial steps meant taking a risk of a lethal infection.
TB reactivation and bacterial pneumonia were particularly bound
to cold exposure, poor diet and unhealthy conditions.

One day a kid was running and freezing in the rain
The day after he had a bad cough and  very high fever
Within one week the young boy had died of pneumonia.

"I ragazzi della via Paal"
"The Paul Street Boys" by Ferenc Molnár (Hungary 1906)
Nemecsek

http://www.fszek.hu/_Images/konyvtaraink/kozponti_konyvtar/olvasoi_terek/olvasotermek/irodalmi_es_nyelvi_olvasoterem/a_pal_utcai_fiuk/000023556_03.jpg.jpg [Links inactive - To make links active and clickable, login or click here to register]

Memory in the Minds: A Book
What on earth does make someone Hungarian? School and school textbooks certainly do. Now, with the the old, rigid system of Hungarian education dying out (there are more and more kinds of school, with diverging curricula), there are fewer and fewer 10-year-olds forced to read the same books. For our generation the sole exception to the compulsury bores at that age was The Paul Street Boys by Ferenc Molnár. That funny, emotional juvenile classic about basic moral values, about the birth of a metropolis, about the meaning of life.

Last year Corvina Publishers brushed up a translation from 1927 and re-issued the book in English. Now you too, friends of Budapest, can have the luck of reading and recommending it to your kids. ( The Paul Street Boys . Translated by Louis Rittenberg, Revised by George Szirtes. Corvina Books, 1994. ISBN 963 13 3801 0)

iko

[profnick]

Mmmm some confusion methinks. Firstly humans are warm blooded. The proper term is homoiothermic; this means that we regulate our body temperature to a constant 37 deg.C. So going out in the cold will not change your internal body temperature or that of the cells in which your immune system is fighting the cold virus. Also getting a cold virus does not "compromise the immune system" though it may tax it somewhat, (hence the increased temperature and fever). It is much more likely that the secondary bacterial infection to which we are prone when we get a cold virus may be more rampant if we waste our energy on maintaining body temperature, (when we go out in the cold weather), than on fighting the infection.

[iko]

Mmmm some confusion methinks. Firstly humans are warm blooded. The proper term is homoiothermic; this means that we regulate our body temperature to a constant 37 deg.C. So going out in the cold will not change your internal body temperature or that of the cells in which your immune system is fighting the cold virus. Also getting a cold virus does not "compromise the immune system" though it may tax it somewhat, (hence the increased temperature and fever). It is much more likely that the secondary bacterial infection to which we are prone when we get a cold virus may be more rampant if we waste our energy on maintaining body temperature, (when we go out in the cold weather), than on fighting the infection.

Hi profnick,

The fact that we regulate our internal temperature at 37°C
does not necessarily exclude that our skin and respiratory tract (from
nostrils to alveoli) are cooled off or warmed up by airflow.
Frost bites are an example of damage from extreme freezing.
The lower air temperature is externally, the stronger the cooling effect.
Multiple factors and individual characteristics play the game
in keeping naughty bugs under control.
Our heating system has its limitations against freezing or warming
in the external environment by 'convention' (air) or contact (water).

Cool eh?

ikod  

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P.S.  I think you meant "homeothermic"

[Karen W. (OP)]

 Well That is interesting and helps me understand a bit more.. Thankyou..

[profnick]

ikod,
True but my point was that the internal cell milieu temperature is (under non extreme conditions) not likely to be a factor in combatting pathogens; which was the original question.
Homeothermic, homoiothermic, homotherm are synonyms (see http://www.wordwebonline.com/en/HOMOIOTHERM [nofollow])
and (http://www.nature.com/nature/journal/v325/n6105/abs/325582c0.html [nofollow])

[iko]

profNick,

this is an extreme example because of immune-depression,
(I mentioned individual characteristics infact) to stress
my point about cold exposure and failure of defence.
There are many others if you 'surf' on PubMed.

Lethal fulminant S. aureus sepsis in M. Behcet overnight cold exposure.

Finsterer J, Schmidbauer M.
Neurological Hospital Rosenhugel, Vienna. duarte@jet2web.cc

Whether patients with Behcet's disease (BD) and immunosuppressive therapy are generally prone to acquire severe infectious diseases is unknown. A 48-year-old man under corticosteroids and azathioprine for BD since 1995 was admitted because of a transitory ischemic attack.
Between the third and fourth hospital day he was accidentally locked up, insufficiently dressed, in the hospital's chapel over night. On the following day, he developed fever and deteriorating consciousness until he became comatose. CT scans of the brain were normal and there was only a slight pleocytosis. Despite adequate therapy, the patient's condition further deteriorated such that he died. Responsible for his decline was a fulminant sepsis, diagnosed upon fever, increased C-reactive protein, thrombocyte decline, multi-organ failure, rhabdomyolysis, growth of S. aureus on blood culture, at autopsy.
Patients with BD and immunosuppressive therapy, may be more vulnerable to infections and may develop lethal overwhelming sepsis already after overnight cold exposure.

Acta Med Austriaca. 2002;29(4):143-5.


Prolonged cold exposure seems to affect even the gut defense systems:

Effect of chronic cold stress on intestinal epithelial cell proliferation and inflammation in rats.

Kaushik S, Kaur J.
Postgraduate Institute of Medical Education and Research, Department of Biochemistry, Chandigarh, 160012, India.

The present study evaluated the effect of chronic cold stress on intestinal epithelial cell proliferation and inflammation. Male Wistar rats were subjected to cold exposure for three weeks. At the end of the cold exposure, intestinal cell proliferation, luminal nitrite and protein levels, intestinal myeloperoxidase activity and mast cell numbers were evaluated. Severely compromised proliferation rate of the crypt-base cells was observed under chronic stress conditions. Cells isolated from stressed rats showed a decreased DNA content in villus and lower villus cell fractions and an increased DNA content in the crypt cells, as compared to controls. Chronic cold stress resulted in increased luminal nitrite, luminal protein levels, and intestinal myeloperoxidase activity. The number of mast cells was significantly elevated under chronic stress conditions. Chronic cold stress resulted in a compromised intestinal epithelial cell proliferation rate and induced inflammation in the rat small intestine, through the combined action of nitric oxide, neutrophils and mast cells.

Stress. 2005 Sep;8(3):191-7.

[iko]

...and when you already caught a flu:

Environmental exposure and the flu.
 
Flu epidemics occur during the winter months (in the United States) because that is when the virus is spread across the country. It has nothing to do with being outside in cold weather. However, the risk of pneumonia is increased by cold exposure. So it's a good idea to bundle up.

...from:  http://www.flushotsvirginia.org/preventflu.shtml [Links inactive - To make links active and clickable, login or click here to register]

[Karen W. (OP)]

Thank you IKO!! Thats kind of how I was told..

[GBSB]

Does a flu epidemic and risk of pneumonia during the winter months affect only humans or affect as well animals (wild and domestic).

I guess it affect only humans but I am not sure and I appreciate if anybody can tell a little bit more.

Luka

[profnick]

Iko,
I appreciate the point about the extreme case when the immune system is compromised and exposure to cold is extreme. The original question though was about why we are told not to go out in cold weather with a cold; maybe not so extreme a situation? To address the most recent points, pneumonia is a generic term for infection of the lung and usually refers to secondary bacterial infections following on from viral malaise. Wild animals do get both viral and bacterial diseases but not the same ones as us. I guess the most commonly known ones are; bovine TB, Foot & mouth, Viral haemmorhagic disease, and rabies, (which we can catch of course).

[iko]

Ok, let's get stuck for a few hours
in a freezer and see what happens!





...I suspect that as a kid you never read
"The Paul Street Boys" by Ferenc Molnár (Hungary 1906)

iko

[rosy]

Purely anecdotal, but...
when I was playing a lot of waterpolo, and consequently spending a lot of time wandering about in winter with wet hair, I definitely found that a cold/cough took longer to clear up than it did before or does now (even though I'm a couple of years older and immeasurably less fit).

I don't think I caught more colds, or not significantly more, but I am absolutely sure that they persisted for longer... several weeks, as opposed to generally less than one.

[iko]

Thank you rosy,
I want to strenghten this point:
in the pre-antibiotic Age, just
a couple of generations before us,
this was a very serious issue.
Not following these simple recom-
-mendations could have made the
difference between survival and
death.

Never forget the old-wives!     Allow me a citation...repetita juvant!

...little bits from vitamindcouncil.com
just a 'basic' website for this topic!

http://www.nature.com/news/2002/020107/images/oldwive_160.jpg [Links inactive - To make links active and clickable, login or click here to register]

Bits Of Wisdom: Those 'old wives' might be on to something

For many years, the "old wives" have been ridiculed as superstitious know-nothings.
Now science seems about to vindicate them.
The old wives maintained that a dose of cod-liver oil would do a body good.
Many children dreaded it because it tasted so awful. But come the dark days of winter, mothers and grandmothers insisted that all family members should hold their noses and swallow a spoonful of cod-liver oil.
During the past 20 years, this practice has gone the way of the manual typewriter.
Few children get cod-liver oil these days.
Doctors don't recommend it because it seems like such an unscientific relic of the past.
The vitamin D that is abundant in cod-liver oil has numerous health benefits though, especially in the winter. That's because levels of vitamin D frequently drop when people are not exposing their skin to the sun.
Cold, dreary weather and diminished sunlight can create borderline vitamin D deficiency in a surprising number of people. In Boston, 42 percent of people studied had too little vitamin D in winter. In Calgary, Canada, almost no one maintains adequate vitamin D in the winter.

In 2005, a psychiatrist who treated his patients for vitamin D deficiency noticed something odd. Influenza hit hard at the Atascadero State Hospital, a maximum-security psychiatric hospital. His ward was spared, with not a single person catching the flu, even though they had been exposed to the virus just like everyone else. The psychiatrist wondered whether the vitamin D he had prescribed had anything to do with their immunity.
This question led to an interesting review of research and a credible hypothesis.
Studies in the past 70 years hint at a connection between vitamin D and overall immunity.

The active form of vitamin D greatly increases the body's production of a natural infection-fighting chemical called cathelicidin. Cathelicidin seems to help fight off illnesses caused by bacteria, fungi and viruses, including influenza.
This might help explain why people are more susceptible to colds and flu in the winter. If their vitamin D levels drop, so does their production of cathelicidin and their overall resistance to infection.

Vitamin D also appears to have anti-cancer activity. People who get regular sun exposure are less susceptible to common cancers that affect the colon, breast, prostate, ovaries and lungs. Even conditions like multiple sclerosis, arthritis and Type 2 diabetes are less common in people with ample vitamin D levels.

Vitamin D has long been associated with stronger bones, but there is also research showing that it contributes to stronger muscles and fewer falls in the elderly.

The old wives did not have sophisticated scientific tools or methods, but they were skilled observers.

It's fascinating when the scientists supply the explanation behind their wisdom.

...

from:      Winston-Salem Journal, Tuesday, November 28, 2006.
http://www.journalnow.com/servlet/Satellite?pagename=WSJ%2FMGArticle%2FWSJ_BasicArticle&c=MGArticle&cid=1149191909636&path=!living&s=1037645509005 [Links inactive - To make links active and clickable, login or click here to register]

Old  Wives

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[profnick]

Iko,
If you read my earlier posts carefully I think you'll find that we are in complete,(if somewhat heated) agreement regarding secondary bacterial infections, since your references and your comment on pre-antibiotics relate to bacterial infections.

[iko]

...with a little help from Rhinology and viruses:
4xC = Cardiff Common Cold Centre... How neat!

http://www.killallanimals.com/killers/rhino.jpg [Links inactive - To make links active and clickable, login or click here to register]

Acute cooling of the body surface and the common cold.

Eccles R.
Common Cold Centre, Cardiff School of Biosciences, Cardiff University, United Kingdom.

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.

Rhinology. 2002 Sep;40(3):109-14.

[iko]

...Present scientific opinion dismisses any cause-and-effect relationship between acute cooling of the body surface and common cold. 

This is probably what profNick referred to.
For me, a good reason not to trust blindly
some - I don't mean all - of the so
called "present scientific opinions".
Remember the 'old wives' and carefully
check your... 'experts'!

iko

[profnick]

"For me, a good reason not to trust blindly
some - I don't mean all - of the so
called "present scientific opinions".
Remember the 'old wives' and carefully
check your... 'experts'!"
Couldn't agree more; I assume you've checked this source? This was an interesting though far from conclusive study with a very small group of subjects who sat with their feet in cold water for 20 minutes a day for a week, (hardly what you' experience by a trip to the shops on a cold day). Even then the chances of them catching a cold compared to a control group were statistically dubious. So check your numbers as well as your experts.

[iko]

Hi profNick,
The data you cited are from a further study, aren't they?

Acute cooling of the feet and the onset of common cold symptoms.

Johnson C, Eccles R.
Common Cold Centre, Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3US, UK.

BACKGROUND: There is a common folklore that chilling of the body surface causes the development of common cold symptoms, but previous clinical research has failed to demonstrate any effect of cold exposure on susceptibility to infection with common cold viruses.
OBJECTIVE: This study will test the hypothesis that acute cooling of the feet causes the onset of common cold symptoms.
METHODS: 180 healthy subjects were randomized to receive either a foot chill or control procedure. All subjects were asked to score common cold symptoms, before and immediately after the procedures, and twice a day for 4/5 days. RESULTS: 13/90 subjects who were chilled reported they were suffering from a cold in the 4/5 days after the procedure compared to 5/90 control subjects (P=0.047). There was no evidence that chilling caused any acute change in symptom scores (P=0.62). Mean total symptom score for days 1-4 following chilling was 5.16 (+/-5.63 s.d. n=87) compared to a score of 2.89 (+/-3.39 s.d. n=88) in the control group (P=0.013). The subjects who reported that they developed a cold (n=18) reported that they suffered from significantly more colds each year (P=0.007) compared to those subjects who did not develop a cold (n=162). CONCLUSION: Acute chilling of the feet causes the onset of common cold symptoms in around 10% of subjects who are chilled. Further studies are needed to determine the relationship of symptom generation to any respiratory infection.

Fam Pract. 2005 Dec;22(6):608-13.

Yes. There is weak evidence, if any, I agree with you.
But I seem to be fascinated by incomplete studies mainly.
In a recent past, I tested on my skin what 'weak evidence' means.
By the way, did you read 'the Shanghai report' in childhood leukemia topic?
Could you comment on that short essay?
I would really appreciate.
Common cold is quite boring indeed.

ikod

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[profnick]

Yeah you're right I think we've done enough on this one. I'll have a look at the report you mention if I get the chance, (I have 32 grant proposals to review in the coming week!).