Is there evidence of antibiotic resistance in bacteria (any species)
being caused by exposure to silver, including colloidal silver?

rosemary25,

I believe what you may be referring to is a statement similar to this
one:
“Unlike antibiotics, Colloidal Silver can be taken indefinitely
without fear of microorganisms developing a tolerance to it.”
http://www.archangelhealth.com/life-force/csilv.htm

While there is no arguing that antibiotics are being over prescribed
today, one does not develop a resistance to antibiotics by taking
colloidal silver, or being exposed to silver.
In order to develop an antibiotic resistance, you need to be taking
antibiotics. Simply put, resistance occurs when bacteria, after
exposure to antibiotics, mutate. It’s their way to defend themselves
in a hostile, antibiotic-saturated world. Bacterial DNA is altered
during the mutation process in response to antibiotic exposure. This
altered DNA, through  bacterial reproduction, is  passed along to
future bacterial generations. The strains of bacteria that become
resistant , become predominant. Thus, more and more bacteria become
resistant to antibiotics. According to this site, bacteria can develop
resistance to disinfectants, pesticides, and fungicides. (I’ve heard
that cockroaches develop a resistance to pesticides too!)
http://whyfiles.org/038badbugs/mechanism.html

http://www.niaid.nih.gov/factsheets/antimicro.htm

http://www.infectionspotlight.com/resistance_1


Back to the colloidal silver. I have found no reliable evidence that
these “remedies” actually work. Because anyone can “publish” anything
on a website, it is especially important to evaluate web sites for
reliable health information. I have not found any supportive evidence
of colloidal silver’s antibacterial claims on any of the health
websites that I trust. In order to better explain bacterial antibiotic
resistance however, lets assume for a moment, just a moment, that
colloidal silver works as a bacteriostatic  agent. The colloidal
silver would work in a different way than antibiotics. It would kill
the bacteria quickly, by interrupting its oxygen supply, and
suffocating the bacteria. (According to the site below). The bacterial
cell has no time to develop a resistance, as it is killed immediately.
With antibiotics, the weaker bacteria are killed quickly, but the
stronger of the species can survive. These “strong” bugs are the ones
that alter their DNA to resist bacteria, and pass this resistant gene
to their offspring. Over time, we have a whole new generation of
resistant bugs!
http://www.quackwatch.org/01QuackeryRelatedTopics/PhonyAds/silverad.html

Back to bacterial antibiotic resistance. A person can develop a
penicillin-resistant  infection, but it doesn’t mean that the organism
is resistant to ALL antibiotics. By culturing a bacteria, medical
technologists in the lab can perform antibiotic resistance
(susceptibility) studies to see which antibiotic would work best on
that particular bug.
http://www.jsonline.com/alive/news/nov02/92887.asp

A nice picture of susceptibility testing
http://www.cat.cc.md.us/courses/bio141/labmanua/lab21/abiot.html


I hope this answers your question. If not, please ask for an Answer
Clarification before rating.

Regards,
crabcakes

---

Request for Answer Clarification by rosemary25-ga on 12 Nov 2002 20:08 PST

A large amount of silver will kill any germ - bacteria or virus. 
Colloidal silver,  however, is taken in very low concentrations,
usually, about 20 parts per million in some cases: too low to kill but
enough to affect what mutations the bacteria will have.

According to at least one medical doctor, exposure to silver will
cause certain bacteria to become resistant to antibiotics that the
patient has never taken. (This happened to me with chloramphenicol)
The doctor is very credible - Dr. Heidi Otter is the head of the
medical association in  British Columbia, Canada.

Archangel.com is not a good source for reliable information on
colloidal silver - it is a  website devoted to selling natural health
products.

Please try to dig up at least one scientific or medical study on TRACE
amounts of silver causing bacterial mutation and/or antibiotic
resistance.

I would also appreciate knowing where best to look for such studies:
The NIH, medical journals, universities, British agencies.

Read Neil's comment.   Thankyou for your assistance.

---

Clarification of Answer by crabcakes-ga on 12 Nov 2002 21:01 PST

Hello rosemary25,
I will be looking for the additional reports. It may take me a day or
two. Thank you for your patience.
crabcakes

---

Clarification of Answer by crabcakes-ga on 13 Nov 2002 08:55 PST

rosemary25,

Thank you for clarifying your question! 

I have researched for a very long time and found practically nothing
backing up the statement that  silver (of any form) can cause
bacterial mutation or resistance. I mean no disrespect to neilzero in
his well-intentioned  comment, but notice his use of the word “
likely” and lack of reliable documentation to support his statemwnt: 
“genetec (sic) selection occurs as a result of exposure to silver much
as it does to to other antibiotics.”

It is true that silver has bacteriocidal properties, but I am doubtful
colloidal silver will ever replace more conventional treatment, as it
is simply not proven to be effective as an oral medicament . Without
launching into molecular genetic or biochemistry, it is unlikely that
ingesting silver would cause resistance to an antibiotic. I am not
saying it can’t happen,  but I can find scant evidence of it.  As I
explained in the first part of the answer, assuming silver kills
bacteria, it would so rapidly. The organisms are dead, meaning they
are unable to genetically mutate. Antibiotics on the other hand, kill
the bacteria more slowly, by interfering with protein synthesis of the
bacterial cell. The weaker ones die sooner, leaving the stronger
organisms to survive, and genetically build a resistance to the
antibiotic. Bacteria double in number roughly every twenty minutes,
and multiply exponentially. The potential for generations of resistant
bacteria to be “born”in large numbers are great. Lets use a fish tank
as an analogy.  You have two fish tanks of guppies. Each tank has some
very strong and healthy guppies who had been well fed and cared for,
and some weaker guppies, sickly and poorly fed. If you were to pour a
poison, say cyanide into the first tank, all the guppies would die,
immediately. The second tank has been accumulating algae, so you pour
in an aquarium approved algicide. You accidentally  made the
concentration a tad too strong and the weak guppies die. The stronger,
more resistant fish survive while ingesting small quantities of the
algicide. These resistant guppies produce babies who are genetically
more resistant to the algicide. This is similar to how silver
presumably kills bacteria, and how antibiotics kill bacteria.
http://cpmcnet.columbia.edu/news/review/archives/medrev_v1n1_0002.html

http://tcdb.ucsd.edu/tcdb/tcfamilybrowse.php?tcname=2.A.6


States bacteria do not build a resistance to silver like they do to
antibiotics.
http://www.silvercolloidal.net/


This is all I was able to find that supports resistance to antibiotics
caused by silver:

Small  Indian study of resistance to silver , ampicillin ,
carbenicillin , tetracycline  and chloramphenicol and the bacteria 
acinetobacter BAUMANNII BL54
http://www.sums.ac.ir/IJMS/9812/shakiba9812.html

A discussion of the benefits of silver.(Please note the disclaimer at
the bottom of the page)
http://www.ihealthsol.com/

This site talks about the merits of silver, and touts a book by John
Hill  D.C. . (D.C. means he is a chiropractor). The site claims that
their information is supported by medical literature, yet none is
cited.
http://www.clspress.com/silver.html

http://www.positivehealth.com/permit/Articles/Miscellaneous/wilson26.htm

http://www.svpvril.com/AgBIBLIO.html


While colloidal silver may be effective against some organisms, it
apparently is ineffective in killing anthrax!
http://medicinegarden.com/ThingsThatDontWork.html


I searched the Food and Drug web site, and found that they have not
approved colloidal silver.
“Use of colloidal silver ingredients in food-producing animals
constitutes a potentially serious public health concern because of the
possibility of residues in milk or meat. According to several
scientific publications mentioned in the October 15, 1996 Federal
Register proposal, the human consumption of silver may result in
argyria -- a permanent ashen-gray or blue discoloration of the skin,
conjunctiva, and internal organs. “
http://www.fda.gov/cvm/index/updates/silver.html
http://www.fda.gov/cder/warn/cyber/2001/Cyber084.pdf
http://www.fda.gov/bbs/topics/ANSWERS/ANS00971.html

Dr. Heide Oetter  is indeed the president of the B.C Medical
Association, but I found no reference for her approval of colloidal
silver, or that she has supported the idea that taking silver (in any
form) causes antibiotic resistance. I found numerous political
references to her however. It appears she really champions her causes!

 http://www.bcma.org/ArbitrationUpdates/DrOetter-Speaking_Notes.asp

http://www.bcma.ca/WhatsNews/InTheNews/HansenProposalSpeakingNotes.asp

http://cbc.ca/stories/2002/05/29/bcdocs020529


Reliable medical sites I searched for your question:

http://www.mdexpress.com/  

http://www.ama-assn.org/

http://jama.ama-assn.org/

http://emedicine.com

http://www.nlm.nih.gov/

http://www.bmn.com  

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed
 
rosemary25, I wish you the best, and hope you find the clarification
more helpful. If Dr. Heidi Oetter is your physician, perhaps she’d be
willing supply you with her documentation, as I have not been able to
find more than I am posting here.

Regards,
crabcakes

---

Request for Answer Clarification by rosemary25-ga on 24 Nov 2002 22:19 PST

Go to www.ncbi.nih.gov..  PubMed has several  articles on "silver" and
"antibiotic resistance".  Type in those search terms.  There are at
least two articles that deal  with the subject, but the one I most
recently looked at was by Grewal, J.S. He suggests that bacteria
resistant to at least one metal ion are MDR (multi-drug resistant).

These articles in PubMed appear very useful.  But they are often only
abstracts.
I didn't find the related articles very helpful.  Do you have any
background in science/biology? Where would you go for more
information?

---

Clarification of Answer by crabcakes-ga on 25 Nov 2002 09:20 PST

Hello again,

I have done further research for you, but have found virtually no new
information proving antibiotic resistance due to silver. (It seems
information on antibiotic resistance and silver is resistant to being
found!)I have found some abstracts suggesting that organisms can
become resistant to silver, and that some organisms are resistant to
both silver and antibiotics, but I can get you no hard proof that
silver causes antibiotic resistance, other than the few abstracts I
have listed below. I must mention that Google researchers do not have
access to special databases beyond what you and the general public can
reach. All of the following abstracts offer the full
article for a fee.

In the abstract by Grewal, that you mentioned, this statement --- “ A
direct correlation between the metal ion and antibiotic resistance was
found in MDR strains.”I can not, however, find further reference to
this study. All of the PubMed abstracts that I found on silver and
antibiotic resistance were linked to sites where you could purchase
the articles by subscription.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10472128&dopt=Abstract

Using PubMed to search “silver” and “Antibiotic resistance” I found
the following abstract:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=Display&DB=PubMed
The full article is available only to paid subscribers, and is found
here, in case you wish to subscribe:
http://mic.sgmjournals.org/cgi/content/full/147/12/3393?view=full&pmid=11739772

Here is a quote from this abstract by Gupta A, Phung LT, Taylor DE,
Silver S., University of Illinois
“Silver compounds are used as antimicrobial agents in medicine and
bacteria that develop resistance to silver cations (Ag(+)) pose
problems similar to those of antibiotic-resistant bacteria. The first
set of Ag(+) resistance genes (sil) was from plasmid pMG101…”
This indicates that strains of bacteria are building a resistance to
the silver cations (Ag+) , and makes no mention that the bacteria
become resistant to other antibiotics.

In this abstract, by Tambe SM, Sampath L, Modak SM. Department of
Surgery, Columbia University, an in vitro study was run to determine
resistance to antimicrobials in medical devices. Used were antiseptic
cleaning solutions containing silver sulphadiazine, triclosan, and
chlorhexidine.
“There was no substantial change in susceptibility to the antiseptic
chlorhexidine when used alone or in combination with either silver
sulphadiazine or triclosan”
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11328769&dopt=Abstract

This very brief abstract references silver’s use in avoiding infection
in wounds.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11183049&dopt=Abstract

Sewage water is studied in Morocco and it is noted that bacteria
resistant to heavy metals such as cadmium, zinc, mercury and zinc also
were resistant to antibiotics. However, this does not imply that
silver exposure caused the antibiotic resistance.
Filali BK, Taoufik J, Zeroual Y, Dzairi FZ, Talbi M, Blaghen M.,
Universite Hassan II, Casablanca, Morocco.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10915198&dopt=Abstract

In this older abstract from the Lancet, 1975 Feb 1;1(7901):235-40, it
was found that burn patients acquired  strains of S. typhimurium that
were resistant to ampicillin and chloramphenicol, but not to silver
compounds, all in vitro. At the time of the writing, however, no
source of resistance is known.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=46385&dopt=Abstract

You can read more about the biochemical properties of silver here:
http://umbbd.ahc.umn.edu/periodic/elements/ag.html


I hope this helps you out. I agree with you that the abstracts are not
very helpful. After a truly exhaustive search, it appears there has
simply been little research in this area.With today’s advances in
molecular biology, genetics and DNA, perhaps more information (with a
silver lining) will be forthcoming. Other sites you may find helpful
(which I have searched as well) are:

National Library of Medicine
http://dirline.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~BAAJlaOes:18

Medical search portal:
http://www.srv.net/~msdata/US_medsearch.html
Regards,
crabcakes


Search strategy:
Silver + antibiotic resistance
antibiotic susceptibility + silver

rosemary25-ga,
Are you aware that alot of the information out there on colloidial
silver as an all-natural cure-all is in fact incorrect.  I have
visited many of the sites myself and with my knowledge in biology and
chemistry, alot of what is said is absolutely ludicrous. I have
sources and information backing up the truths behind the lies of
colloidial silver.  Would that suffice?

-Tox-ga

Likely colloidial silver has minor health benefits and`kills some
bacteria and makes others sick, so genetec selection occurs as a
result of exposure to silver much as it does to to other antibiotics.
Unless lots of people start injesting silver, resistance to colloidal
silver will grow slowly over the years instead of rapidly for other
antibiotics being perscribed by the millions. Human diets have had
trace amounts of silver for thousands of years, so most bacteria
developed resistance to silver centuries ago.  Neil

Had to get in on this one.  Your best bet is to search extensively at
PubMed on the NCBI web site; you can link there by directing your
browser to www.ncbi.nih.gov.  Though I have not done as an extensive a
search as others that have posted, I must concur with the opinion that
there is precious little LEGITIMATE scientific literature regarding
the use of colloidal silver as an antibiotic and even less speaking to
its tendency to select for resistant bacterial strains.  The only
article that I found was in an obscure Norwegian medical journal—not
exactly a hotbed of sound scientific work).  It is clear, however,
that colloidal silver can turn you literally blue (see 
http://www.cnn.com/2002/US/Central/10/02/candidate.blue.skin.ap/)
This former Montana senatorial candidate, in a state of Y2K induced
paranoia (he thought that Y2K would disrupt the world's supply of
antibiotics), consumed enough colloidal silver, to turn his skin blue
permanently.  That’s enough to make it aversive to me!