HIV Not Linked to SIV-Contaminated Polio Vaccines, Study Says

HIV was not introduced into the human population through oral polio vaccines used in the 1950s in Africa that were contaminated with simian immunodeficiency virus, according to a study published on Wednesday in the journal Science, Reuters reports (Reaney, Reuters, 4/21). Although most scientists agree that HIV evolved from the related SIV, they disagree on how the virus crossed over from chimpanzees to humans, according to AFP/Yahoo! News (AFP/Yahoo! News, 4/21). The OPV/AIDS theory claims that tissue from SIV-infected chimpanzees was used in the preparation of polio vaccines that were administered to about one million people in what was then the Belgian Congo region (Munro, CanWest/National Post, 4/22). The site of the 28 vaccination projects correlated closely with the earliest cases of HIV, according to BBC News (BBC News, 4/21). The polio vaccine theory was first brought to light in a 1992 Rolling Stone article and was then expanded by former BBC journalist Edward Hooper in a 1999 book, titled "The River: A Journey Back to the Source of HIV and AIDS" (Kaiser Daily HIV/AIDS Report, 4/26). Michael Worobey of the University of Arizona and colleagues collected specimens from chimpanzees in the area and found that the chimps were infected with a previously unknown form of SIV, which they named SIVcpzDRC1 (CanWest/National Post, 4/22). SIVcpzDRC1 belongs to a different strain of SIV than the strain that is related to HIV, according to the researchers. They said that their findings -- along with the absence of detectable SIV or chimp DNA in stocks of the original vaccines -- "should finally lay the OPV/AIDS theory to rest."

Reactions, Implication
"Although Worobey's new research is helpful, the chimp groups his team has sampled are far from being representative of the chimpanzees that were used for the polio vaccine research," Hooper said. He added he believes Worobey's research does not refute the OPV/AIDS theory, according to Reuters (Reuters, 4/21). However, Worobey said that "HIV-1 did not originate from polio vaccines that were tested in that area in the 1950s," but he added that further research is needed to determine how SIV "jumped" to humans, according to BBC News (BBC News, 4/21). Worobey currently is collaborating with Congolese scientists to research how HIV mutates. "HIV has this massive genetic diversity ... [a]nd we need to have a better understanding of that mutation in order to craft a vaccine to top the virus," Worobey said (CanWest/National Post, 4/22). The research finding is important because the OPV/AIDS theory currently is hampering World Health Organization polio immunization efforts in Nigeria, according to the Birmingham News (Parks, Birmingham News, 4/22). Some Muslim leaders in Northern states of Nigeria have said that the immunization effort is part of a U.S. plan to decimate the Muslim population by spreading HIV/AIDS and infertility (Kaiser Daily HIV/AIDS Report, 2/26). "Given [that] the fears about the safety of polio vaccines are currently threatening the global campaign to eradicate the disease, our clear-cut evidence against one of the key sources of concern is timely," Worobey said (Reuters, 4/21).