OPV AIDS hypothesis

The oral polio vaccine (OPV) AIDS hypothesis posits that the AIDS pandemic originated from live polio vaccines prepared in chimpanzee tissue cultures and then administered to up to one million Africans between 1957 and 1960 in experimental mass vaccination campaigns.

Data analyses in molecular biology and phylogenetic studies contradict the OPV AIDS hypothesis; consequently, scientific consensus regards the hypothesis as disproven. The journal Nature has described the hypothesis as "refuted".

Two vaccines are used throughout the world to combat poliomyelitis. The first polio vaccine, developed by Jonas Salk, is an inactivated poliovirus vaccine (IPV), consisting of a mixture of three wild, virulent strains of poliovirus, grown in a type of monkey kidney tissue culture (Vero cell line), and made noninfectious by formalin treatment. The second vaccine, an oral polio vaccine (OPV), is a live-attenuated vaccine, produced by the passage of the virus through non-human cells at a sub-physiological temperature. The passage of virus produces mutations within the viral genome, and hinders the virus's ability to infect nervous tissue.

Both vaccines have been used for decades to induce immunity to polio, and to stop the spread of the infection. However, OPV has several advantages; because the vaccine is introduced in the gastrointestinal tract, the primary site of poliovirus infection and replication, it closely mimics a natural infection. OPV also provides long lasting immunity, and stimulates the production of polio neutralizing antibodies in the pharynx and gut. Hence, OPV not only prevents paralytic poliomyelitis, but also, when given in sufficient doses, can stop a threatening epidemic. Other benefits of OPV include ease of administration, low cost and suitability for mass vaccination campaigns.

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