Date: 24 Oct 2002 16:19:13 -0500 From: jcummins <jcumm...@uwo.ca> Subject: millions infected with SV40 cancer virus from vaccines
We are far too slow in acknowedging that SV40 causes cancer in humans. Science Oct 25 2002: 725-727 Creeping Consensus on SV40 and Polio Vaccine Dan Ferber At first it seemed impossible: The widely celebrated polio vaccine that was given to millions of people in the 1950s was contaminated with a monkey virus--a virus that causes cancer in animals. Since the virus was discovered in the monkey kidney extracts used to make the Salk vaccine some 40 years ago, concern has risen that the vaccine, which wiped out polio in the United States, might have triggered an epidemic of cancer (Science, 10 May, p. 1012). Now, at the request of the U.S. Congress, an expert panel of the Institute of Medicine (IOM) has issued the most definitive judgment to date, allaying most--but not all--of those fears. The virus, known as SV40, has not caused a wave of cancer, the panel concluded. But it might be causing some rare cancers, and more research is needed to find out. Since the contamination was detected, government researchers and others have published epidemiological studies that they said proved that the vaccine was safe. But questions remained, because the virus kept turning cultured cells cancerous, and it kept causing tumors in animals. That debate heated up in the past decade, after researchers began finding SV40 DNA in four types of rare human cancers--the same kinds it causes in animals--and press reports emphasized that tens of millions of people could have been exposed. The IOM committee examined the 4 decades of epidemiology to see whether people exposed to SV40-contaminated vaccine have a higher risk of cancer. Although the studies were flawed, the panel concluded, they were good enough to show that no cancer epidemic has occurred. But millions of people might have been infected with SV40 from the contaminated vaccine, the panel wrote. And the evidence is strong enough to suggest, but not prove, that the virus can sometimes cause human cancer. "We acknowledge that SV40 at least could have a carcinogenic effect, but epidemiological evidence does not suggest that it actually did," says IOM committee member Steven Goodman, a biostatistician at Johns Hopkins School of Medicine in Baltimore. Even so, he adds, "there's a body of evidence [on SV40 carcinogenicity] that has to be taken quite seriously." The committee stressed the need for more reliable and sensitive tests to detect SV40 in human tissue, especially tests for anti-SV40 antibodies in human blood. Once those tests are devised, researchers could test human tissue samples from before 1955 for the monkey virus to ascertain whether it really came from contaminated polio vaccine. In addition, the panel said, there's enough evidence that the virus is spreading in humans that the issue should be studied further. But overall, the IOM report "really closes the book on the discussion" of past epidemiological work, says pediatric oncologist Robert Garcea of the University of Colorado Health Sciences Center in Denver. Although SV40 might yet turn out to cause cancer in humans, the risk, if any, is "not remotely in the ballpark" of well-known carcinogens such as tobacco smoke or asbestos, adds Goodman. The report seems to have satisfied protagonists across the spectrum, although they're drawing different conclusions. One reason, Goodman explains, is that IOM took extraordinary precautions to prevent conflicts of interest, excluding anyone who had ever sat on a government vaccine panel or received money from government or industry for vaccine research. Virologist Janet Butel of Baylor College of Medicine in Houston, Texas, is "gratified that they recognized the biological evidence" implicating SV40 in cancer. Keerti Shah of Johns Hopkins School of Medicine, a long-time skeptic, calls the report "a positive step," although he'll need better assays before concluding that SV40 is indeed present in humans. If the National Institutes of Health follows the panel's suggestions, more money should soon be available to probe the link. -- The silver-list is a moderated forum for discussion of colloidal silver. Instructions for unsubscribing may be found at: http://silverlist.org To post, address your message to: silver-list@eskimo.com Silver-list archive: http://escribe.com/health/thesilverlist/index.html List maintainer: Mike Devour <mdev...@eskimo.com>
