SILVER IS A BROAD SPECTRUM ANTI-VIRAL BY PAUL MAHER, MD
Here is an authoritative paper by Paul Maher, MD, a contributor to http://energyscienceforum.com and it is jam-packed with accurate information as well as a lot of references.
This is provided for informational purposes only and we recommend that you follow your own doctor’s medical advice. Get the paper in PDF format here: Silver is a Broad Spectrum Antiviral
Silver is A Broad Spectrum Anti-Viral
Paul Maher, MD MPH, 3/22/2020
Silver has been understood from antiquity to have anti-infective properties. In our time various silver based preparations and formulations are commonly employed as wound dressings, as treatment for topical infections and for water purification. The antifungal,ii anti-protozoaliii and broad spectrum anti-bacterial properties of silver have been well-researched and documented in medical studies. Somewhat more recently the broad spectrum anti-viral activity of silver has become more widely recognized and documented. This review will examine the peer-reviewed medical literature relating to the anti-viral properties of silver with specific attention paid to anti-viral activity of silver against enveloped viruses and, in light of the recent COVID-19 viral pandemic, what studies may be available specifically concerning the activity of silver against coronaviruses.
Before beginning a brief note concerning terminology is appropriate. The majority of studies referenced, refer to the activity of “nano” particles of silver. Nanosilver is a somewhat nebulous term, but generally is seen to refer to silver particles with diameters in the 10-100 nanometer range or sometimes. Such silver nanoparticles may be generated by a variety of chemical, biological and physical means, to include electrolysis. Particles of silver of sufficiently small diameter, nano particles, when placed in water will, due to Brownian motion and the repelling action of like charges, remain dispersed in solution for a long time to indefinitely. Such a solution is termed a colloidal solution of silver particles, (colloquially, “colloidal silver”) . As silver, if unbound to other elements has a positive charge one also occasionally hears the term “ionic silver” employed.
In 1975 Chang et al.vi, documented in-vitro activity of silver sulfadiazine against Herpesvirus hominis virus, noting drug activity was proportional to duration of exposure and concentration of silver sulfadiazine. Herpesvirus is an enveloped DNA virus.
Similarly, in 1999, Stozkowskavii and Wroczyńska-Pałka researched the activity of silver sulfathiazole against Herpes virus stating, “This drug suppresses or completely inactivates the infectivity of virus. The antiviral effect is directly related to concentration of the drug and duration of exposure.” The researchers also noted a similar activity with silver nitrate while sulfathiozole alone, without silver, did not show anti-viral activity.
Human immunodeficiency virus (HIV), the well-known cause of AIDS, is an enveloped, RNA retrovirus virus. Viral cell entry is mediated by the interaction of a glycoprotein, 2 gp120, embedded in the viral membrane with the cluster of differentiation (CD4) receptor protein found on the surface of immune cells. In 2005, Elechiguerra et al. published, “Interaction of silver nanoparticles with HIV-1”.viii
Silver nanoparticles produced from three different approaches were found, in-vitro, to prevent cell entry of the HIV virus. The authors state, “For all three nanoparticle preparations, at silver concentrations above 25 μg/mL, (25 ppm) viral infectivity was reduced to an extent that it could not be detected by syncytium formation”. Through electron microscopy scanning studies the authors concluded that particles in the size range of 1 to 10 nanometers were binding to the virus and responsible for preventing viral cell entry. Further, the binding of the silver particles was not random but was selective for the protruding gp120 glycoproteins most likely in the area of dilsulfide bonds on this protein. The resulting
steric hindrance from the attached silver prevented viral entry into the cell. While, as
will be noted later, there appear to be additional mechanisms of anti-viral action
mediated by silver, this research, in addition to documenting the absence of HIV viral
cell entry, provides a plausible mechanism of action for how silver might block cell
entry of enveloped viruses. COVID-19 is an enveloped virus whose cell entry is
mediated, per early research, by interaction of the viral membrane spike glycoprotein
with the Angiotensin II Converting Enzyme(ACE II) receptor protein.ix
Hepatitis B is a small double stranded, enveloped DNA virus. In 2009 Lu et al.x
the results of in-vitro study examining the interaction of silver nanoparticles and the
hepatitis virus. These silver particles were created chemically from silver nitrate and
designed to have particle diameters of either approximately 10 nanometers or
approximately 50 nanometers. The researchers found that both sizes of particles
reduced extracellular virus formation by greater than 50%. While silver did not have an
effect on intracellular viral DNA, it did inhibit the formation of viral RNA from this
DNA template, a necessary step in infection. The authors conclude, “Silver
nanoparticles could inhibit the in vitro production of HBV RNA and extracellular
virions. We hypothesize that the direct interaction between these nanoparticles and HBV
double-stranded DNA or viral particles is responsible for their antiviral mechanism.”
As silver was found to inhibit formation of messenger RNA post viral infection, this
would indicate a second possible mechanism of action of silver against viruses in
addition to the blockage of viral cell entry, as the authors speculate, perhaps mediated by
interaction of silver with viral DNA.
Human respiratory syncytial virus (RSV) is an enveloped RNA virus. In 2008 Sun et alxi
reported results of in vitro research finding that PVP coated silver nanoparticles at low
concentrations inhibited RSV infection by 44%. Monkeypox virus is an enveloped
RNA virus within the orpthopox virus genus. While the virus generally infects animals
it may cause zoonotic infections in humans leading to a disease somewhat similar in
presentation and course to smallpox. Rogers et al. reported results on research
examining inhibition of monkeypox viral plaque formation from exposure to silver
nanoparticlesxii. Nano particles created from plasma gas synthesis and polysaccharidecoated silver nanoparticles in ranges from 10 to 100 nanometers were examined at
dosages ranging from 25 – 200 ug/ml. No concentration of nanosilver exhibited
cytotoxicity at the dosages examined. Silver nanoparticles of 55 nanometers and
polsaccharide coated silver particles of 25 nanometers demonstrated a statistically
significant dose dependent decrease in viral plaque formation. Other particle sizes did
not lead to statistical significance with some sizes and dosages leading to non-significant
increases in plaque formation.
Following the earlier work of Chang and Stozkowska, Baram-Pinto et al.xiii created
silver nanoparticles capped with mercaptoethane sulfonate and studied their effect on
Herpes simplex virus. These silver nanoparticles led to the blockage of viral entry into
cells and “prevention of subsequent infection”. Mercaptoethane sulfonate alone showed
no anti-viral activity. Vijayakumar and Prasad reported on results of creation of silver
nanoparticles embedded in a carbonaceous matrixxiv “This carbonaceous matrix
embedded silver nanoparticles showed antimicrobial properties against both bacteria
(Gram-positive and Gram-negative) and virus (M 13 phage virus). The bactericidal
effects were noticed even after washing and repeated exposure of these carbon
supported silver nanoparticles to fresh bacterial cultures, revealing their sustained
activity”. Similarly, De Gusseme et al.xv created silver nanoparticles utilizing a
bacterium as both a reducing agent and silver matrix, resulting in nanoparticles in the
0.9-11.2 nanometer range. This nanosilver when applied to a carbon filter led to a 3.8
log reduction in water with murine (mouse) norovirus. The authors conclude, “This is
the first report to demonstrate the antiviral efficacy of extracellular biogenic Ag0
promising opportunities for continuous water disinfection”.
Arenaviruses are a family of non-enveloped RNA viruses responsible for a variety of
serious viral hemorrhagic fevers. Speshock et alxvi examined the interaction of silver
nanoparticles with the Tacribe, arenavirus. Silver did not inhibit viral entry into Vero
cells grown in culture for these non-enveloped viruses. However, silver nanoparticles in
the size range of 25-50 nanometers “dramatically reduced” viral RNA expression
leading to a significant reduction in progeny virus. The authors conclude, ”Silver
nanoparticles are capable of inhibiting a prototype arenavirus at non-toxic
concentrations and effectively inhibit arenavirus replication when administered prior to
viral infection or early after initial virus exposure”.
Silver has been examined by multiple researchers for its effect on influenza virus.
Mehrbod et alxvii reported nanosilver inhibited viral entry of this enveloped virus. Xiang
et alxviii reported that silver nanoparticles in the 10 nm range inhibited influenza A as
evidenced through a variety of assays. For instance, the hemagllutination assay is a
commonly employed method for quantifying the concentration of influenza virus. The
authors state, “In the presence of silver-nps, the ability of H1N1 influenza A virus to
agglutinate erythrocytes was either reduced or completely inhibited”. Mori et al.xix
created silver nanoparticles complexed with chitosan (lobster shell) with particles sizes
ranging from 3.5 to 12.9 nanometers. All sizes of particles exhibited a dose dependent
inhibition of influenza A, while chitosan alone demonstrated no anti-viral activity.
Since 2013 research on the antiviral properties of nanosilver has increased greatly.
Adenoviruses are non-enveloped DNA viruses that are a frequent cause of the common
cold. Chen et alxx report a dose dependent decrease in adenovirus type 3 viral DNA in
cultures treated with nanosilver, concluding, “the present study indicates silver
nanoparticles exhibit remarkably inhibitory effects on Ad3 in vitro”.
Vaccinia virus, a large enveloped DNA virus closely related to Smallpox virus, has been
well studied as the viral agent responsible for the eradication of smallpox disease
through vaccination. Trefry et al.xxi report that 25-nm silver nanoparticles inhibited viral
entry into cells, “The silver nanoparticles caused a 4- to 5-log reduction in viral titer at
concentrations that were not toxic to cells. Virus was capable of adsorbing to cells but
could not enter cells in the presence of silver nanoparticles”.
Xiang et al.xxii reported results on research into silver nanoparticles and human H3N2
influenza virus. The unconjugated nanosilver was created chemically through an
oxidation-reduction reaction of silver nitrate with sodium carbonate and tannic acid. No
information is provided on the resulting silver particle sizes. At dosages from 6.25 to 50
ug/ml there was no observed cytotoxicity to the examined cell lines. Silver nanoparticles
were shown to decrease to a statistically significant degree growth of influenza virus as
indicated by the hemagglutination assay and likewise to decrease cell apoptosis (death).
Electron microscopy studies found destruction of morphological viral structures through
interaction with silver particles starting from 30 to 120 minutes post exposure. This
study is also notable for the report of animal in-vivo results. Mice inoculated
intranasally with nanosilver demonstrated significantly enhanced survival after exposure
to H3N2 influenza virus, specifically none of the control group mice survived while
75% of those inoculated with nanosilver intranasally survived. Treated mice also
showed “lower lung viral titer levels and minor pathologic lesions in lung tissue”.
Gaikwad et al.
xxiii reported on in-vitro results of nanosilver’s effects against Herpes
simplex virus types I and II and Human Parainfluenza virus type 3. Nanoparticles in this
instance were produced from a fungus based approach. Average particle size was
estimated to vary from 20 to 50 nanometers. The Vero cell assay was used to determine
cytotoxicity of silver to cells. Antiviral activity was measured at concentrations ranging
from 0.1, to 10 μg/mL by observing the number of viral plaques in Vero cell
monolayers as compared to controls. Cell cytotoxicity was not observed at the
concentrations evaluated. Treatment showed a consistent decrease in replication
efficiency for Herpes simplex type I and Parainfluenza virus and a minor effect on
Herpes simplex type II virus. Interestingly, the particular fungal species used in
preparing the nanosilver had a considerable effect on anti-viral activity. The authors
speculate that the differences may be due to variations in particles size and/or zeta
potential (charge) from samples prepared from different fungi. They write, “From the
present study it was observed that AgNPs were capable of controlling viral infectivity,
most likely by blocking interaction of the virus with the cell, which might be dependent
on the size and zeta potential of the AgNPs”.
Moving on to 2014, the following study, “Inhibitory effect of silver nanomaterials on
transmissible virus-induced host cell infections” by Lv et al.xxiv is notable in the present
context. The authors state that, “transmissible gastroenteritis virus (TGEV) is an
economically significant coronavirus that can cause severe diarrhea in pigs”. The
authors note that human corona viral infections including the recent MERS and SARS
outbreaks are a public health concern and so the researchers chose TGEV Coronavirus
as a model for human Coronavirus infection. Four types of silver nanoparticles were
examined to include silver nanowires of 60 and 400 nanometers and silver nanoparticles
of 10 and 20 nanometers. Swine testicle (ST) cells were cultured in Dulbecco’s
modified Eagle’s medium and cell viability determined using the “MTT” assay. PCR,
Western Blot, immunofluorescence and flow cytometry assays were also performed.
The silver nanowires and 20 nm nanosilver particles decreased cell apoptosis (death)
from corona virus infection. The MMT assay demonstrated that these three silver
formulations also led to a dose dependent reduction in viral titers. Interestingly, the 10
nm silver particles did not show an anti-viral effect. However the Polyvinylpyrrolidone
capping agent used as a stabilizer was 4 fold higher in the 10 nm silver particles as
compared with the 20 nanometer particles and the authors speculate this may have had
an effect on the anti-viral activity as compared with the other three silver formulations.
Through further research the authors find that one plausible mechanism of action for
silver’s anti-viral activity in this study was from interaction with the p38/mitochondriacaspase-3 signaling pathway which plays a role in mediation of cell apoptosis.
The authors conclude from their research, “Our data indicate that Ag NMs are effective
in prevention of TGEV-mediated cell infection as a virucidal agent or as an inhibitor of
Hu et al.xxv confirmed the anti-viral activity of silver nanoparticles against Herpes
simplex virus type II as evaluated through plaque formation assay and MMT assay
stating, “Therefore, 100 μg/mL Ag-NPs could completely inhibit HSV-2 replication. AgNPs at nontoxic concentrations were capable of inhibiting HSV-2 replication when
administered prior to viral infection or soon after initial virus exposure.”
Khandelwal et al.xxvi demonstrated that silver nanoparticles derived from silver nitrate
and with a size range of 5-30 nanometers at a nontoxic concentration inhibited
replication of a Morbillivirus that may afflict livestock. Orlowski et al.xxvii reported that
tannic acid modified silver nanoparticles in the size range of 13 to 46 nanometers
inhibited Herpes simplex type II viral infection in-vitro and in-vivo in mice. Closing out
2014, Swathy et alxxviii published research on a surprising synergism between silver
nanoparticles and carbonate ions. The researchers, “discovered that 50 parts per billion
(ppb) of Ag(+) released continuously from silver nanoparticles confined in nanoscale
cages is enough to cause antimicrobial activity in conditions of normal water.” By way
of context, sodium fluoride is often added to water supplies at a level of 1-2 parts per
million, so this is a concentration of silver some 1/20th to 1/40th that of added fluoride.
The authors go on to state, “the antibacterial and antiviral activities of Ag(+) can be
enhanced ~1,000 fold, selectively, in presence of carbonate ions “ While not discussed
by the authors baking soda is an extremely inexpensive source of carbonate ions.
Sujitha et al.xxix 2015 reported success in controlling Dengue fever viral infection invitro with silver nanoparticles. Treatment with 20ug/ml silver nanoparticles led to a
greater than 4 log reduction in viral titers after six hours. “AgNP were highly effective
against the dengue vector A. aegypti”. Elbeshehy et alxxx report that silver nanoparticles
in the size range of 72-92 nanometers show activity against Bean Yellow Mosaic Virus.
Fatima et alxxxi report in 2106 that silver nanoparticles created using Cinnamomum
cassia as a reducing agent effectively and non-toxically inhibited H7N3 Influenza A
virus infection of a cultured Vero cell line. Somewhat similarly, Yang et al.xxxii also
report in 2106 that silver nanoparticles using curcumin as a reducing agent showed a,
“highly efficient inhibition effect against respiratory syncytial virus (RSV) infection,
giving a decrease of viral titers about two orders of magnitude … no toxicity was found
to the host cells”. Bekele et alxxxiii examined the activity of silver nanoparticles of 10,
75, and 110 nanometers against feline calicivirus. At dosages of 50 and 100 ug/ml the
10 nanometer particles, “inactivated the FCV (feline calicivirus) beyond the limit of
detection”. The larger 75 and 110 nanometer particles did not show anti-viral activity.
Borrego et al.xxxiv report that a proprietary formulation of silver nanoparticles was
effective in preventing Rift Valley fever viral infection of a Vero cell line.
Also in 2016 Chen et al.xxxv created silver nanoparticle impregnated graphene oxide
sheets. This material was tested for activity against infectious bursal disease virus and
feline coronavirus (FcoV). The silver impregnated sheets reduced viral infection by
feline coronavirus by 25% as compared to 16% for graphene oxide alone. While
certainly not a dramatic result this is a second confirmatory study that silver has antiviral activity against viruses of the corona virus family.
Another interesting study from 2016 was published by Li et al.xxxvi. The researchers
describe “decorating” the surface of the antiviral drug oseltamivir (Tamiflu) with silver
nanoparticles and comparing the in-vitro efficacy of this combination to silver alone and
oseltamivir alone for ability to inhibit H1N1 influenza. Quoting the researchers,
“Compared to silver and oseltamivir, oseltamivir-modified AgNPs (Ag@OTV) have
remarkable inhibition against H1N1 infection, and less toxicity was found for MDCK
cells by controlled-potential electrolysis (CPE), MTT, and transmission electron
microscopy (TEM). Furthermore, Ag@OTV inhibited the activity of neuraminidase (NA)
and hemagglutinin (HA) and then prevented the attachment of the H1N1 influenza virus
to host cells.” This finding is significant in that oseltamivir is one of the drugs currently
being researched and utilized as a possibly useful treatment for COVID-19 infection. In
this study regarding influenza virus, silver was seen to have a synergistic effect with
While there are further positive studies of anti-viral activity from 2017 to the present,
due to constraints of time the literature review will be truncated here. It is trusted that to
a reasonable reader the above suffices to convincingly make the case that silver is a
potent and broad spectrum anti-viral. It should also be noted that by no means have these
studies been “cherry picked”. While there are some studies with less dramatic findings,
some studies where some of the particular dosages, particle sizes or formulations in a
given study were not effective, in this literature review I have not seen a single article
reporting absence of anti-viral activity against any virus that was researched.
The above research was almost uniformly in-vitro (test-tube) studies, it is unfortunate
that more in-vivo data is not available at this time for this very promising anti-viral.
Further, many issues relating to the in-vitro studies, how do we prevent the silver from
clumping in the growth media we are using, for instance, are not at all directly
applicable to the in-vivo system, where the question would instead by what is the
behavior of nanosilver in the albumin rich milieu of blood plasma.
There are literally dozens of approaches to generating nanosilver with one recent article
reviewing a number of physical, chemical and biologically oriented approachesxxxvii
One means of generating nanosilver has been conspicuously absent from the studies
published in the literature to date, namely the way the great scientist and experimenter,
Michael Faraday first created colloidal metals nearly two hundred years ago, through
electrolysis. This approach is not at all complicated, for instance to create colloidal
silver one would start with two wires or strips of 99.9% pure silver. One silver wire is
connected to the positive of a DC voltage source, say a nine volt battery, the other wire
to the negative of the battery. The two wires, and only the wires, are placed in water
separated by a distance of 1/8th to one half inch to allow the water to act as a resistor.
Over the course of a few minutes a cloud of microscopic silver is seen to appear in the
water. Over time this silver would eventually electroplate on the negative electrode,
however, due to the like positive charges on the small silver particles, and the Brownian
motion of water, the majority of the silver stays in solution as a colloid. If one has a
total dissolved solids meter, costing perhaps 20 dollars, one can document the
concentration in parts per million of colloidal silver as the process proceeds. If one
starts with tap water with 200 ppm dissolved minerals and impurities when one reads
220 ppm dissolved solids one knows one has 20 ppm silver in that water. In a pinch, if
one has two 99.9% pure silver dollars, one could also use those to create colloidal silver
following the same procedure. Two silver wires weighing only a few grams and costing
a few dollars could produce literally tens of gallons of colloidal silver before themselves
being dissolved through electrolysis. This treatment would cost pennies per day.
When one sees a slight cloudy white tinge to tap water, this is generally a concentration
in the range of 10-40 ppm. Hence, even if one does not have a dissolved parts meter one
can eyeball a reasonable concentration by observing a very slight cloudy tinge to the
water. If, as will be discussed further, one uses distilled water one will see a slight
cloudy yellow tinge to the water instead of whitish, again consistent with a 10-40 ppm
Peter Lindemann, PhD, has published non peer-reviewed results of characterization of
silver particles produced through electrolysis.xxxviii By electron microscopy
characterization, low voltage electrolysis of silver in tap water is reported as generating
particles in the size range of 50 to 150 nanometers. While on the large size of those
particles showing efficacy in the previously reviewed literature, this is within the size
range of particles that showed anti-viral activity in some studies. Silver generated by
electrolysis in distilled water was found to have a particle size of around 4 nanometers.
This smaller particle size, secondary to the Tyndall effect shows a yellowish tinge,
reflective of the small particle size. As smaller particle sizes were generally associated
with greater antiviral activity in the above review, I concur with Dr. Lindemann’s
position that ideally one might wish to create colloidal silver with distilled water. There
is a caveat to that position however, which again refers to use of silver in-vivo.
Unfortunately, the pharmacodynamics and pharmacokinetics of nanosilver are for the
most part uncharacterized in peer-reviewed literature at this time. Nonetheless, one
point is fairly obvious. About the first thing colloidal silver taken by mouth will
encounter is stomach acid. Stomach acid is primarily hydrochloric acid. Silver
dissolves in hydrochloric acid. Hence, while colloidal silver created with tap water has a
slightly larger particle size than one might wish when considering the previous
literature, it would seem a fairly safe bet that due to the activity of hydrochloric acid on
silver, the particle sizes reaching the blood stream would comprise a range consisting of
particles smaller than those ingested. More simply, I would say, do not despair about
making useful anti-viral colloidal silver if one doesn’t have distilled water. While it
would be nice to have distilled water, clinically the two approaches may likely yield
similar results. I would further recommend Dr. Lindemann’s write-up on this topic as a
useful guide to creating colloidal silver. Again, however, do not be intimidated, one
doesn’t have to “overthink” this. Take two strips of pure silver connect them to a nine
volt battery stick the strips (not touching each other) in a glass of water. Make sure only
silver is in the water as one is not trying to create colloidal alligator clip. In 2-5 minutes
or so with tap water one will see a slightly cloudy tinge, one is done. If using distilled
water at nine volts this will take 1-2 hours and one will see a slight yellowish tinge. Dr.
Lindemann mentions using, I believe, a tablespoon or two of 10-20 ppm colloidal silver,
I am perhaps a bit more radical as every couple weeks I brew up 8 ounces of 10-20 ppm
colloidal silver made from twice filtered tap water and gulp it down, it is some of the
best tasting water you will come across. I also make a second glass and pour it through
a carbon (Britta) water filter and use that filter for my drinking water for the next two
Colloidal silver, made from a variety of means has been used as a health tonic by
hundreds of thousands of people by this time. The primary, and only that I am aware of,
concerning health side effect reported from this usage appears to be a very rare
occurrence of bluish skin discoloration known as argyria. While it is arguable, whether
argyria is seen only with ingestion of silver salts such as silver nitrate or also with
prolonged use of colloidal silver, yes, if one drank gallons of 100 ppm colloidal silver
for years and never looked in a mirror, one might theoretically find a serious problem
with skin discoloration. This side effect might be compared with the, still widely used
antibiotic, gentamicin, which causes a rare, acute, sometimes irreversible hearing loss.
Further, some commonsense is in order, two strips of wire weighing a few grams will
suffice to make tens if not hundreds of gallons of colloidal silver before themselves fully
dissolving. This is not at all like a child munching down chips of lead based paint, this
is a very, very small amount of silver, likely a dose orders of magnitude less than the 50
mg of elemental zinc one might take, and correctly so, as a supplement without a second
In addition to a reasonable safety profile established through years of use by at minimum
hundreds of thousands of people, there are numerous testimonies of health benefits,
sometimes dramatic, from individuals using colloidal silver made electrolytically from
tap water and possibly distilled water as well. I will not delve into this literature as there
are I realize some readers who might find the presentation lessened if evidence is
expanded outside of the peer-reviewed literature. I would just pose as a philosophical
question, if one can identify the identity of an individual patient and has no reason to
suspect a financial or other bias to their reporting, should the patient’s description of
their own symptomatology and disease course be considered more or less authoritative
than the second hand case report written up by their physician in a medical journal? As
a corollary, who would be expected to more often have a financial or emotional bias to
distort results of a health intervention, a patient or a health practitioner? These are
questions far outside the scope of this write-up except to note that the evidence
presented has been solely from the peer-reviewed medical literature to keep from turning
away those purists who feel strongly that this is all that should be taken into
Lastly, in addition to taking colloidal silver internally, if one knew they were not going
to be able to wash their hands with soap and water for a time, applying colloidal silver
water topically might help to prevent spread of disease in the same way that silver
impregnated wound dressings are used as anti-infectives for difficult to treat wounds.
One might also consider making a concentrated glass of colloidal silver and pouring it
into the end of a wash cycle for laundry, or simply soaking laundry in colloidal silver
before drying, so as to have silver impregnated clothing. The literature for silver as an
effective antibacterial against both gram positive and negative bacteria is more
voluminous than what has been presented here for its’ anti-viral activity. It bears noting
that what often is fatal for someone acquiring a viral pneumonia is the injured lungs
developing a superseding bacterial infection which the patient in a weakened condition
is unable to fight off.
In summary, silver is well-documented in the peer reviewed medical literature to be a
broad spectrum anti-viral, silver is also a broad spectrum anti-bacterial. Two in-vitro
studies have documented activity of silver against animal corona viruses. In the current
context of COVID-19 spread it is urgent and imperative that health researchers and
authorities examine the in-vitro and in-vivo activity of silver against this novel corona
virus. One reasonable mechanism of action by which silver interferes with viral entry is
by binding to the thiol residue disulfide bridges of surface glycoproteins of enveloped
viruses as documented in the literature. Silver has demonstrated highly selective viral
toxicity in-vitro. Colloidal silver, used appropriately and reasonably, has a track record
of years of safe use. Colloidal silver with particle sizes identical to those showing
activity in the medical litrature may be generated cheaply and easily through
One should not provide a false hope, one is also and perhaps more culpable, for failing
to disclose a reasonable hope. Colloidal silver may or may not be effective against
COVID-19, those studies need to be performed, the above provides a reasonable hope
that it could be effective. Hospitals overwhelmed with viral illness will be hard pressed
to provide appropriate care to all but the most ill, while someone with a common cold
who goes to a hospital to be tested for COVID-19 runs a very high risk of now being
infected with this highly contagious bug even if they weren’t before they visited the
hospital. Colloidal silver has a track record of safe use, costs a couple cents or less for
per eight ounce glass, and can be made in a few minutes with a nine volt battery and a
couple strips of 99.9% pure silver. Perhaps the most appropriate question one might ask
is, what have you got to lose?
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