Close menu
September 30, 2021 Big Pharma Views

Big Pharma

How a Cancer-Causing Monkey Virus Ended Up in Polio Vaccines

In the 1950s and 1960s, research conducted in the search for a polio vaccine involved “passaging” the poliovirus through monkeys — a process that led to some of the vaccines becoming contaminated with a cancer-causing simian virus.

Did you know that a cancer-causing monkey virus contaminated millions of batches of polio vaccine?

Did you know that a cancer-causing monkey virus contaminated millions of batches of polio vaccine?

Did you know this virus has now been found inside people and inside their cancers?

The health authorities would like the American public to forget these facts. But it happened, and the repercussions are still with us today.

This known contamination took place at the end of the 1950s and the beginning of the 1960s, but may have continued for the next 40 years. In fact, over the last 60 years, cancer rates for every age group in America have continued to climb.

How did this vaccine contamination happen? And is there a link to the skyrocketing rates of cancer in the United States?

How were polio vaccines contaminated with cancer-causing monkey virus?

In the 1950s, scientists like Drs. Jonas Salk and Albert Sabin had isolated the poliovirus strains to make vaccines.

Salk’s strains would be inactivated with formaldehyde and injected into children. Sabin’s strains would be attenuated, or weakened, by transferring or passaging the live viruses through different host cells, and then fed to children orally.

Because his goal was to create a live attenuated vaccine, Sabin had to isolate the poliovirus strains and then passage the strains through various host cells in order to attain the right virulence — strong enough to illicit an immune response, but weak enough so as to not cause polio in the recipient.

Sabin’s oral polio vaccine (OPV) is a trivalent vaccine and was, therefore, comprised of three types – Type I, II, and III.

Here’s how Type I was created. In 1941, Drs. Thomas Francis and Thomas Mack isolated the Mahoney poliovirus “from the pooled feces of three healthy children in Cleveland.”

Then, to make his vaccine, Salk subjected the polio virus strain to passages through 14 living monkeys and two cultures of monkey testicular cultures. In 1954, the strain (now called Monk14 T2) was given to Drs. C.P. Li and M. Schaeffer, who subjected the virus to nine more passages through monkey testicular cultures.

Next, the strain (now called Monk14 T11) underwent 15 more passages in monkey testicular cultures, 18 passages in monkey kidney cells, two passages through the skin of living rhesus monkeys, and additional passages through African Green monkey skin and monkey kidney cell cultures.

This strain was now called MS10 T43 or LS-c.

In 1956, Sabin took this polio virus and passaged it through seven cultures of African Green Monkey kidney cells. That same year, the pharmaceutical company, Merck, Sharp & Dohme, passed the strain (now called LS-c, 2ab/KP2) through a rhesus monkey kidney cell culture.

The resulting material, called Sabin Original Merck (SOM), was provided to the pharmaceutical company Lederle in 1960, as the seed material to manufacture its polio vaccine.

Types II and III were created in a similar fashion.

Why was so much ‘passaging’ through animal cells necessary?

The theory of passaging is relatively simple. The idea is that as a virus becomes more adapted to a new animal species, that strain will become less adapted to its original host.

Putting the virus into various monkey tissues or cultures, including monkey kidneys, monkey testicles and monkey skin, was designed to adapt the polio virus to monkeys.

Once it was adapted to monkeys, so the theory goes, the polio virus would be less virulent for humans. While the idea made sense, what did not make sense were the risks of doing this.

Each time the polio virus was harvested from these monkey tissues and cultures, the scientists ran the risk of picking up extraneous monkey viruses mixed in with their polio virus.

This is, of course, what happened. In fact, since kidneys filter the blood and remove toxins, they are uniquely situated to be a potential source of viruses.

But the story gets even worse.

How was polio virus grown for vaccines?

Once their polio seeds were isolated, pharmaceutical companies needed a method to produce the vast quantities needed for nationwide immunization campaigns.

This required a medium or substrate upon which the poliovirus could be efficiently grown and harvested. Kidney cells from rhesus, and later African Green monkeys, were chosen because they were found to be an effective growth medium.

Monkeys were imported in large numbers from various countries. They were killed and their kidneys were removed. A small quantity of poliovirus would then be added to the minced kidneys, and within a few days, large quantities of poliovirus could then be harvested from these pulverized monkey kidneys cells.

There was a problem, however, with using monkey kidney cells to both create the original vaccine strains and grow the vaccine in large quantities: Monkeys are full of monkey viruses.

In fact, there were so many simian viruses identified in the polio vaccines that scientists started numbering them. Simian Virus 1, then 2, etc. Then they started abbreviating them: SV1, SV10, etc.

What is SV40?

SV40 was the 40th virus found in rhesus monkey kidney cells when these cells were used to make the polio vaccine. This particular virus contaminated both the Inactivated Polio Vaccine (IPV) created by Salk, and the oral or “live” Polio Vaccine (OPV) created by Sabin.

As discussed below, SV40 was determined to be oncogenic, or cancer-causing.

SV40 is in the family Polyomaviridae, which includes JC virus (JCV) and BK virus (BKV). Polyomaviruses are small DNA viruses.

The SV40 genome encodes for various proteins, including “Large T-ag.” This protein stimulates host cells to enter the phase where the cell multiplies its genetic content prior to cell division. In addition, T-ag binds to various cellular tumor suppressor proteins.

In other words, SV40 helps stimulate human cells to multiply, and also stops the cellular machinery designed to stop cancer from starting. It’s a deadly “one-two punch.”

How was SV40 discovered in the polio vaccine? Dr. Bernice Eddy of the National Institutes of Health (NIH), Division of Biologics, discovered it when, in 1959, she took the material used to grow polio vaccines and injected it into hamsters.

Tumors grew in the hamsters, so Eddy wanted to isolate the causative agent — and it turned out to be SV40, the 40th simian virus contaminating the polio vaccines.

Her discovery was validated by Drs. Maurice Hilliman and Benjamin Sweet of Merck.

What did the scientists say?

Many scientists knew using monkey kidneys full of simian viruses was a dangerous way to make a vaccine.

As early as 1953, Dr. Herald R. Cox, a scientist working at Lederle Laboratories, one of the polio vaccine manufacturers, published an article in a peer-reviewed scientific journal in which he stated:

“[P]oliomyelitis virus has so far been cultivated only in the tissues of certain susceptible species — namely, monkey or human tissues. Here again we would always be confronted with the potential danger of picking up other contaminating viruses or other microbic agents infectious for man.”

In 1958, a scientific journal reported, “the rate of isolation of new simian viruses (from monkey kidney cells) has continued unabated.”

Additionally, in 1960, Merck wrote to the U.S. Surgeon General:

“Our scientific staff have emphasized to us that there are a number of serious scientific and technical problems that must be solved before we could engage in large-scale production of live poliovirus vaccine. Most important among these is the problem of extraneous contaminating simian viruses that may be extremely difficult to eliminate and which may be difficult if not impossible to detect at the present stage of the technology.”

What did the regulators do?

On March 25, 1961, the federal regulations that controlled the production of oral poliovirus vaccines were amended. These new regulations did not require the vaccine manufacturers throw away their SV40-contaminated poliovirus seeds, which were the source for all subsequent polio vaccines.

Instead, the rules required that “[e]ach seed virus used in manufacture shall be demonstrated to be free of extraneous microbial agents.”

The new regulations also required that each pair of monkey kidneys removed from a monkey for vaccine production “shall be examined microscopically for evidence of cell degeneration.”

Furthermore, fluid from the monkey kidney cells had to be combined with other tissue cultures in order to detect if there was any contaminating virus. The regulations required that “[t]he cultures shall be observed for at least 14 days.”

In essence, these regulations required an SV40 test that was comprised of taking the monkey kidney cells upon which the vaccine would be grown and:

  • Look at them through a microscope to see if they demonstrated SV40.
  • Take fluids from them.
  • Introduce those fluids into other cell cultures.
  • Wait 14 days.
  • Determine if the other cell cultures were changed as a result of the presence of SV40.

What were some of the problems with the test?

These tests were not designed to detect the contaminating viruses themselves. One cannot see SV40 or any virus with a standard light microscope or the naked eye.

Instead, the government’s SV40 test relied on the observation of the presumed effect of an SV40 infection on certain tissue cells to demonstrate the presence of the virus.

In fact, the regulations required only a 14-day observation period, even though it was well documented that the effect they were looking for (“vacuolating change”) could take up to six weeks for SV40 to show itself with this method:

“In this laboratory in [Green Monkey Kidney] GMK cultures inoculated with small quantities of virus [(SV40)] (i.e., <100 TCID50), changes were not observed until five or six weeks after inoculation. Therefore to attain maximal accuracy with this method, a long period of observation is required.”

These quality control steps were designed to appease the pharmaceutical companies because they did not require that the companies throw anything away and start over.

The steps also did not protect the public because they did not ensure the removal of SV40 from the vaccines for a number of reasons, including:

  • The original seed stocks that were known to be contaminated with SV40 were not thrown out, but instead used to make OPV for the next 40 years.
  • The substrate (monkey kidney cells) used to grow OPV were known to harbor SV40.
  • The quality control step was completely inadequate. For example, a 14- day observation period would not detect a virus that could take six weeks to grow.

In fact, in the early 1960s there are multiple scientific papers calling attention to this and suggesting better technologies to detect SV40. The government and pharmaceutical industry ignored these concerns and suggestions.

How was the epidemiology flawed?

After SV40 was originally detected in the Salk and Sabin vaccines which had been administered to millions of children around the world, the scientific community held its breath and wondered if these children would be stricken with cancer when they were young, or later as adults.

Indeed, both the pediatric and adult cancer rates have climbed steadily over the last 60 years. But, the few epidemiological studies that looked for a direct link between SV40 and human cancer provided inconsistent conclusions.

Each of these studies suffered from major flaws, including the fact that no one knew who actually received the SV40-contaminated vaccines and who did not — so it was impossible to compare an SV40-exposed group with a non-exposed group.

Where is SV40 found today?

By 1999, numerous pathologists, microbiologists and virologists throughout the world had detected SV40 in a variety of human cancers, such as brain tumors, including medulloblastoma, bone cancer, mesothelioma and non-Hodgkin’s lymphoma.

Most of these were the very same cancers created when SV40 was introduced into animals.

The question left unanswered for decades now faced scientists again — was SV40 responsible for causing or contributing to human cancers?

Over the years, scientists from around the world have made startling and disturbing discoveries. They have found SV40 antibodies in a significant percentage of people, including children who were too young to receive the SV40-contaminated vaccines of the early 1960s.

Scientists also discovered SV40 is actually inside some human cancers. Furthermore, they determined that SV40 interferes with the genes, like p53, which are necessary for making cancer cells die.

Since genes like p53 help trigger apoptosis, SV40 can make chemotherapy and radiation therapy less likely to be effective.

What did the Institute of Medicine conclude?

In July 2002, the National Academy of Science Institute of Medicine (IOM) Immunization Safety Committee convened a study into SV40 and cancer, which culminated in a report published in October 2002.

According to the IOM report, “SV40 Contamination of Polio Vaccine and Cancer”:

“The committee concludes that the biological evidence is strong that SV40 is a transforming [i.e., cancer-causing] virus … that the biological evidence is of moderate strength that SV40 exposure could lead to cancer in humans under natural conditions, [and] that the biological evidence is of moderate strength that SV40 exposure from the polio vaccine is related to SV40 infection in humans.”

In other words, there was scientific evidence that SV40 wasn’t simply a bystander inside human cancer cells — the scientists concluded the monkey virus could be the cause of the cancer in the person.

What was the government’s response?

Nonetheless, the various U.S. government agencies such as the Centers for Disease Control and Prevention (CDC) and National Cancer Institute, disputed these conclusions.

According to the CDC, “SV40 virus has been found in certain types of cancer in humans, but it has not been determined that SV40 causes these cancers.”

According to the NIH, “the NCI is continuing to evaluate the possible link between SV40 infection and human cancers.”

While the government spends decades “evaluating” SV40, this monkey virus:

  • Has already become prevalent in human populations and inside some human cancers.
  • Is such a strong carcinogen that a search for scientific articles about “SV40 and cancer” reveals more than 6,100 different scientific articles.
  • Makes orthodox cancer therapies less likely to be effective so they cannot save the life of the patient.


SV40 is a potentially deadly human carcinogen and it came from FDA approved and mandated vaccines.

To learn more about SV40, vaccines and cancer read “The Virus and the Vaccine: The True Story of a Cancer-Causing Monkey Virus, Contaminated Polio Vaccine, and the Millions of Americans Exposed” and visit SV40 Cancer Foundation and Our Alexander.

Suggest A Correction

Share Options

Close menu

Republish Article

Please use the HTML above to republish this article. It is pre-formatted to follow our republication guidelines. Among other things, these require that the article not be edited; that the author’s byline is included; and that The Defender is clearly credited as the original source.

Please visit our full guidelines for more information. By republishing this article, you agree to these terms.