From: Billi Goldberg <bigoldberg@igc.org>
Subject: Houston Post 4/5/92
Note: non-commercial reproduction.
Archive-Number: 4813
Organization: UCLA, Computer Science Department
Date: Sun, 5 Apr 92 18:22:34 PDT

The following information has been summarized and excerpted from the 
Sunday, April 5, 1992 edition of The Houston Post with the permission 
of the authors, Tom Curtis and Patricia Manson.  

This article is not copyrighted.

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DISCOVERY TOO GRAVE TO IMAGINE

Could polio vaccine start cancer epidemic?

  Thirty-three years ago, a federal scientist in Washington discovered 
that an infectious agent in the vaccines used to immunize hundreds of 
millions against polio caused tumors in young hamsters.

  Soon scientists across the country confronted the terrifying prospect 
that in trying to do good in eradicating paralytic polio, they might 
have unleashed a global cancer epidemic.

  This evidence -- buried in old medical journals and the memories of 
researchers -- is fueling a debate over the origin of AIDS.  If 
scientists didn't know for sure whether a monkey virus in the polio 
vaccine caused cancer in people, what else didn't they know?  Could 
dangerous viruses have been present in the old vaccines, seeding slowly 
developing diseases in people even as they prevented polio?

  The polio vaccines are made in cultures of monkey kidney tissues, 
cultures frequently contaminated with known and unknown monkey viruses, 
most of which were presumed harmless.

  Eventually, American science heaved a collective sigh of relief and 
declared that the monkey virus that caused cancer in hamsters didn't 
harm people.

  But in the decades that followed, a smattering of disturbing reports 
linked the virus to brain tumors and other cancers in human beings.

  "The people who were responsible for the approval and dissemination of 
the contaminated vaccines back then also apparently controlled the 
funding for follow-up studies, and they did not seem to want to know" 
the long-term effects, charged critic Walter S. Kyle.
 
  Dr. Joseph Melnick, a pioneering virologist in the fight against 
polio, acknowledges that there have been few follow-ups on recipients of 
vaccines contaminated with the virus.  Doctors should follow for life a 
large number of people who got the virus-laced vaccines in order to 
learn the long-term effects, he said.

  After the heart-stopping discovery that a virus in rhesus monkeys 
caused cancer in young hamsters, scientists stopped using those monkeys 
to make polio vaccines.  They switched instead to African green monkeys.

  In the mid-1980s, when more sensitive test were developed, scientists 
found that African greens were the natural host for another virus -- 
simian immunodeficiency virus, or SIV.

  SIV causes a form of AIDS in some monkeys, though not in African 
greens, which show no symptoms of illness.  

  SIV is a kind of cousin to HIV, the human immunodeficiency virus that 
causes human AIDS.  Like HIV, SIV is a member of the lentivirus 
subfamily of retroviruses. 

  Kyle, the author of an articles in the British medical journal Lancet, 
theorizes that the experimental use of an oral polio vaccine to treat 
herpes starting in the mid-1970s sparked the U.S. AIDS epidemic.  He 
suggests the vaccine was contaminated with a virus closely related to 
the one that causes AIDS in humans.

  The virus that gave baby hamsters cancer -- and polio pioneers a jolt 
-- was officially identified in 1960.  It was called SV40 because it was 
the 40th simian, or monkey, virus found.

  It was found to have contaminated a number of batches of polio 
vaccines.

  "That really put the fear of God in us," Melnick admitted recently.  
Still sounding a little incredulous, he added: "We had no idea how that 
would turn out."

  "It (badly scared) all of us," agreed Dr. Thomas H. Weller, one of 
three men who won the Nobel Prize for discovering how to grow polio 
virus in tissue culture.  That achievement led directly to the 
development of polio vaccines.

  "Here was a virus -- we didn't know what it did in man -- that 
produced tumors in hamsters," said Weller, who teaches at Harvard 
Medical School and the Harvard School of Public Health.

  It was well known three decades ago that some viruses which might be 
harmless in the host species could prove deadly when they moved into a 
new species -- like human beings -- that hadn't evolved ways to deal 
with them.

  The harder scientists looked and the more sensitive their testing 
instruments became, the more monkey viruses they found.  

  When Congress finally took a look at the issue of SV40-contaminated 
vaccines in 1961, one polio pioneer, Hilary Koprowski, urged the 
government to change regulations that required vaccine makers to use 
monkey kidney tissue to grow polio virus.

  Koprowski, then director of Philadelphia's Wistar Institute, urged 
that human cell lines be used instead because of all the extraneous 
viruses in primary monkey kidney culture.
  
  But the only remaining vaccine maker in this country, the Lederle 
Laboratories division of American Cyanamid Co., has continued to use 
monkey kidney tissue to grow polio virus.

  Melnick said scientists were concerned about using human cell lines 
because "we didn't know if they carried any viruses we couldn't detect."

  Research is being done now on synthetic cultures whose compositions 
could be varied to tailor-make vaccines, Melnick said.

  Although there seemed to be few direct ties between SV40 and human 
illness initially, troubling evidence about the virus has been mounting 
since the late 1960s, note two authors of a forthcoming journal article, 
"Polio Vaccines and the Origins of AIDS."

  The paper, written by Blaine F. Elswood of the University of 
California San Francisco and Dr. Raphael B. Stricker of the California 
Pacific Medical Center, cites a number of other papers pointing to 
problems with SV40:

   <> The New England Journal of Medicine reported in 1972 that a virus 
related to SV40 was isolated from the brains of two patients with a 
brain tumor called progressive multi-focal leukenopathy 
[leukoencephalopathy] (PML).

   <> Nature, the British science journal, published an article in 1974 
noting that SV40 had been isolated from an advanced case of the virulent 
form of skin cancer known as melanoma.

   <> Six years earlier, Nature had presented findings from an 
Australian study that showed a correlation between polio immunization 
and the development of cancers in children older than 1.

   <> In 1986, German researchers reported finding evidence of SV40 in a 
number of brain tumors.  In 1990, they reported finding an increased 
incidence of brain tumors among people who received polio vaccines 
contaminated with SV40.

  Recent evidence also indicated that SV40 causes a cancerous lesion -- 
called a Kaposi's sarcoma-like tumor -- in nude mice, or those lacking 
an immune system.

  Kaposi's sarcoma (KS) is one of the defining illnesses that strikes 
AIDS patients after their immune systems begin to collapse.  Nobody 
knows whether there is any connection between the development of KS in 
AIDS patients and their immunization with polio vaccine contaminated 
with SV40.

  Elswood and Stricker cite the reports on SV40 to support their theory 
that HIV or precursor viruses may have contaminated live oral polio 
vaccines tested on 325,000 Africans -- from 1957 to 1960.  Those tests 
took place in present-day Zaire, Rwanda and Burundi, regions that are 
among those in Africa reporting the highest incidence of AIDS.

  The vaccine was developed by Koprowski, the man who later proposed 
replacing monkey kidneys with human tissue in vaccine production.

  Before vaccines were developed, polio was an illness that prompted 
panic.  Swimming pools were closed, people stayed away from crowded 
movie theaters and parents kept their children close to home for fear 
they might be crippled for life by a virus that seemed to strike at 
random.

  "Polio was the AIDS of the 1940s and '50s," said Melnick, who played a 
pivotal role in helping medical science choose Dr. Albert B. Sabin's 
sugar-cube-encapsulated live oral polio vaccine as the polio preventer 
of choice.

  A private philanthropy called the National Foundation for Infantile 
Paralysis, popularly known as the March of Dimes, mobilized a scientific 
war against polio and paid for most of the research.
 
  The battle, first to figure out how to grow the virus in tissue 
culture and then to produce effective vaccines, were waged at breakneck 
speed in an effort to prevent future cases of paralysis.

  About 20,000 people in the United States contracted polio each year in 
the early 1950s before the development in 1954 of the first widely 
available vaccine, Dr. Jonas Salk's shots of polio virus killed with 
formaldehyde.

  Both Salk's killed and Sabin's live, attenuated vaccine prompted the 
human immune system to produce antibodies to polio that warded off the 
wild, paralyzing form of the illness.

  Scientists were afraid that publicly airing problems with polio 
vaccines being contaminated with monkey viruses would make people 
reluctant to be immunized.
 
  Even today, Melnick -- whose work earned him a place in the Polio Hall 
of Fame honoring heroes in the battle against the disease -- stresses 
that the possibility of adverse effects from a polio vaccine must be 
weighed against its benefits.

  "You have to be afraid not to take the vaccine," he said.  "If you 
don't take the vaccine, you could have a dead child or a paralyzed 
child."

  Nonetheless, Melnick last month joined Nobel Prize-winner Dr. 
Frederick C. Robbins and Dr. Anthony Fauci, the federal government's 
leading AIDS researcher, in calling for old stored polio vaccines to be 
tested for evidence of HIV or related retroviruses.

  Melnick, 77, and Robbins, 75, say they do not believe HIV will be 
found, but contend that the vaccine stocks should be tested anyway to 
resolve concerns about contamination. 

  Even so, the pioneers of polio vaccines are anxious about what might 
happen if the theories tying the origin of AIDS to polio vaccine prove 
true.

  "This is not a lesson that's going to be useful for the public," 
Robbins fretted.

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